Chapter IV - Timber
Structures
Unified Construction Code of Republic of Kosovo
Chapter IV – Timber Structures
Section 2 – Structural
I. GENERAL PROVISIONS
1.3.2 The fulfillment of the essential
requirements of mechanical resistance and
stability of the structure and of a part of the
essential requirement of fire protection related
to preservation of the load-bearing capacity of a
timber structure in the case of fire during a
certain period determined by a special
regulation (hereinafter: resistance to fire), is
attained with a timber structure that has the
technical characteristics and meets the
requirements laid down in this Regulation.
1.1
1.1.1 This Technical Regulation (hereinafter
referred to as the Regulation), in compliance
with
the fulfillment of the essential
requirements for construction works, defines
the technical characteristics for load bearing
timber structures in buildings (hereinafter
referred to as timber structures), the
requirements for the design ,execution,
usability, maintenance and other requirements
for
timber
structures,
and
technical
characteristics and other requirements for
construction products intended to be
incorporated into the timber structure
(hereinafter referred to as construction
products).
1.4
1.4.1 Construction products made of timber to
which this Regulation applies are:
- Wood products (structural timber beams and
wood based panels)
- Mechanical fasteners
- Adhesives
- Prefabricated elements
- Wood protection products,
1.1.2
This regulation also applies to
components of the building that are not integral
parts of timber structures (non-structural
elements - wood panels, wooden bulkheads,
fences, fill, etc.) i.e., elements of timber
structure that do not affect the mechanical
resistance and stability of the building as a
whole.
- Other construction products for which
requirements have been prescribed in
Appendixes of this Regulation because of their
installation along with the products from
subparagraphs 1 to 5 of this
paragraph.
1.5
1.1.3 This regulation does not apply to final
coatings of structural and non -structural parts
of the buildings (coatings of ceiling, flooring,
and walls) and wood products that serve as
thermal, acoustic or other insulation.
1.5.1 Timber structures and construction
products to which this regulation applies shall
have the technical characteristics and meet all
other requirements laid down in this
Regulation.
1.2
1.5.2 Integral parts of a timber structures
(bracings, foundations, etc.) and construction
products that are incorporated in them, and
which are not covered by this Regulation, must,
in addition to provisions of this Regulation,
fulfill the provisions of a special regulation
which governs such Structures,
1.2.1 Design, execution, maintenance and usage
of building shall be such as to fulfill the
requirements laid down in this Regulation
1.3
1.3.1 The timber structure is part of the building
complex.
110
Unified Construction Code of Republic of Kosovo
Chapter IV – Timber Structures
Section 2 – Structural
II. TECHNICAL CHARACTERISTICS OF A TIMBER
STRUCTURE
and 2.1.2 of this Regulation, it is considered
that the building meets the essential
requirement of mechanical resistance and
stability, and fulfills the specified resistance to
fire.
2.1
2.1.1 The technical characteristics of a timber
structure must be such that during the life of a
building, while complying with the execution
and maintenance specified in the design
documentation of the timber structure, it
withstands
usual
exploitation
and
environmental effects, so that during its
execution and use, foreseeable impacts on a
building do not cause:
- Collapse of a whole or part of the work,
- Major deformations to an inadmissible degree,
- Damage to other parts of the construction
works or to fittings or installed equipment as a
result of a major deformation of the load
bearing construction,
- Damage by an event to an extent
disproportionate to the original cause,
2.2.2 When, in accordance with special
regulations, the additional protection of a
timber structure is necessary in order to meet
the requirements of fire resistance (linings,
sprinkler installation etc.), that protection shall
be an integral part of the technical design
documentation of the timber structure.
2.3
2.3.1 Technical characteristics of the timber
structure must be such that, in addition to
fulfilling the requirements of this Regulation,
requirements of other specific regulations are
also fulfilled which are necessary for fulfillment
of other essential requirements for the building.
2.1.2 Technical characteristics of a timber
structure, along with the requirements of
Paragraph 2.1.1, must be such that in the event
of an outbreak of fire, the load-bearing capacity
of structure or part of it is preserved for a
period of time defined in a special regulation.
2.4
2.4.1 A timber structure shall, after the
reconstruction of a building, have the technical
characteristics as prescribed in paragraph 2.1.1
and 2.1.2 and paragraph 2.3.1 of this
Regulation.
2.1.3 Technical characteristics of a timber
structure referred to in paragraph 2.1.1 and
2.1.2 are accomplished by designing and
constructing the timber structure in accordance
with the provisions of this Regulation.
2.4.2 As an exception to paragraph 2.4.1, a
timber structure must after reconstruction and
adaptation of the building, which does not
significantly affect the technical properties of
the timber structure, have at least minimum of
technical characteristics that it had before
reconstruction and adaptation (hereinafter
referred
to
as
pre-existing
technical
characteristics).
2.1.4 Preservation of technical characteristics of
a timber structure referred to in paragraphs
2.1.1 and 2.1.2 is achieved by the maintenance
of a timber structure in accordance with the
provisions of this Regulation.
2.2
2.4.3 It is considered that the reconstruction of
a building should not affect significantly the
technical characteristics of a timber structure if
2.2.1 If a timber structure has technical
characteristics stipulated in paragraphs 2.1.1
111
Unified Construction Code of Republic of Kosovo
Chapter IV – Timber Structures
Section 2 – Structural
the pre-existing technical characteristics related
to the mechanical resistance and the stability of
the building are satisfactory and if they do not
change more than 10 percent (eg. change of
values of resultant forces in sections, etc.).
solution in design documentation of the timber
structure.
2.5.6 Protection of a timber structure is
specified in more detail in Appendix E of this
Regulation.
2.4.4 The provision of paragraph 2.4.2 of this
Article does not apply:
- To multiple reconstructions of a building which
change the pre-existing technical characteristics
of a steel structure as a whole or in part, which
characteristics are related to the mechanical
resistance and the stability of the building,
- To reconstruction of a building whose timber
structure is damaged so that a danger is present
to the lives and health of people, environment,
nature, other buildings and things, or the
stability of the ground on the surrounding land.
III. CONSTRUCTION PRODUCTS FOR TIMBER
STRUCTURES
3.1
3.1.1 Construction products are produced in
production plants (factories) outside of
construction sites, unless specified otherwise in
this Regulation for certain construction
products.
2.5
3.1.2 An exception to paragraph 3.1.1 of this
Regulation, the prefabricated elements of a
timber structure (hereinafter: prefabricated
elements) may be fabricated on a construction
site for the needs of that construction site.
2.5.1 Technical characteristics of protection of
timber structures must ensure fulfillment of the
requirements set on series of paragraphs 2.1 of
this Regulation.
3.1.3 The construction site, in addition to being
the place as defined by the Construction Law,
implies, within the meaning of paragraph 3.1.2
of this Regulation, a production plant in which
the prefabricated elements, applying suitable
construction technology, are produced or
fabricated for needs of a given construction site
in accordance with the technical design
documentation of a timber structure.
2.5.2 The protection of a timber structure must
be conducted in such way as to ensure the
attainment of technical characteristics of
protection referred to in paragraph 2.5.1 of this
Regulation.
2.5.3 If the protection is conducted in
accordance to standards indicated in Appendix
E of this Regulation, it is considered that the
attainment of the protection characteristics
referred to in paragraph 2.5.1 of this Regulation
is ensured.
3.2
3.2.1 A construction product produced in a
production plant (factory) outside of
construction site may be incorporated into a
timber structure if it fulfills the requirements
laid down in this Regulation and if a certificate
of conformity was issued for it in accordance
with the provisions of a special regulation.
2.5.4 It is allowed to use other standards in
addition to those indicated in Appendix E of this
Regulation if the same level of compliance is
attained.
2.5.5 The protection of a timber structure is
considered to be an integral part of a technical
112
Unified Construction Code of Republic of Kosovo
Chapter IV – Timber Structures
Section 2 – Structural
3.2.2 Prefabricated elements fabricated on the
construction site for needs of that construction
site may be incorporated into a timber
structure if their usability is proven in
accordance with the technical design
documentation of a timber structure and this
Regulation.
must fulfill are laid down in Appendixes of this
Regulation for:
- Wood products– in Appendix A,
- Mechanical fasteners – in Appendix B,
- Adhesives – in Appendix C,
- Prefabricated elements– in Appendix D, and
- Wood protection products – in Appendix E.
3.2.3 In the case of non-compliance of the
construction
product
with
technical
specifications for that product and/or the
technical design documentation of a timber
structure, the producer of a construction
product or the contractor constructing the
timber structure must immediately stop the
production/ installation of that product and
undertake measures for the determination and
removal of the faults which caused the lack of
conformity.
3.3.2 Certifications of conformity of products
that are not covered by standards or deviate
significantly from
standards indicated in
Appendixes A to E referred to in paragraph
3.3.1 of this Regulation are to be conducted
according to technical specifications for such
products.
3.3.3 Certifications of conformity, in terms of
paragraph 3.3.1 and 3.3.2 of this Regulation,
cover the activities of assessing conformity of
construction products and, depending on the
specified assessment system, issuing the
certificate of factory production control or
issuing the certificate of conformity of
construction products.
3.2.4 If there is non-conforming delivery of a
construction product, the manufacturer or
importer must inform, without delay, all buyers,
distributors, authorized legal person that took
part in certifying the conformity and the
Ministry of Trade and Industry.
3.2.5 The manufacturer or the importer and
distributor of the construction product are
obliged to undertake corresponding measures
to maintain the technical properties of a
construction product during handling, storing
and transport, as is the contractor constructing
the timber structure during transport, handling,
storing and installation of a construction
product.
IV. DESIGN OF TIMBER STRUCTURES
4.1
4.1.1 Timber structures must be designed in
such way that during execution of work and
service life of the building, all impacts on the
timber structure must be predicted, resulting
from the method and sequence of construction,
from foreseeable conditions of normal use of
the building and foreseeable impacts of the
environment on the building.
3.3
3.3.1
Specific
properties,
attestations,
certifications of conformity and marking of
construction products, testing of construction
products, and specifics during design and
construction, necessary control procedures and
other requirements that construction products
4.1.2 Technical design documentation of timber
structure, in accordance with this Regulation,
must prove that the building will, during its
construction and the designed usage life, fulfill
the essential requirement of mechanical
resistance and stability, fire resistance and
113
Unified Construction Code of Republic of Kosovo
Chapter IV – Timber Structures
Section 2 – Structural
other essential requirements in accordance
with relevant regulations.
4.3.2 The application of other rules for
designing of timber structures which differ from
the rules laid down in the European standards
indicated in Appendix “F” of this Regulation is
allowed, if it is proven that by applying those
rules the requirements of this Regulation are
fulfilled at least at the level specified in
European standards in Appendix “F”.
4.1.3 If not specified otherwise, with this or
other regulations, the service life of the building
referred to in paragraph 4.1.1 of this Regulation
must be at least 50 years.
4.2
4.3.3 Appendix “F” referred to in paragraph
4.3.1, specifies in more detail the designing of
timber structures.
4.2.1 The mechanical resistance and stability
and also fire resistance of the building are to be
proven in the technical design documentation,
with calculations of load-bearing capacity and
serviceability of the timber structure for
foreseeable actions and impacts on the
building.
4.4
4.4.1 Glued timber must have a water content
corresponding to the technical instructions of
the adhesive manufacturer but not less than 9%
and not more than 15% provided that the
maximum difference between the water
content of elements to be bonded must be ±
2%.
4.2.2 As an exception to paragraph 4.2.1 of this
Regulation, fire resistance does not have to be
proven if by a special regulation is not
determined the period during which the
ultimate limit state of the load-bearing capacity
of the timber structure must be preserved
during fire.
4.4.2 Initial imperfections in the middle of a
linear element, i.e. the deviation from the
direction of the axis of the linear element, and
the slender beams where buckling may occur as
in the frame, must not be greater than 1/500 of
the length for glued laminated timber or 1/300
for structural timber.
4.2.3 The calculations referred to in paragraph
4.2.1 of this Regulation are to be conducted by
suitable calculation procedures that, when
necessary, may be complemented by tests, in
which all relevant parameters must be included.
4.5
4.2.4 Calculation models and other models
must be such that, when the appropriate entry
parameters are used and the modeling is
carried out correctly, correspond to the
behavior of the structure during construction
and use.
4.5.1 It is not allowed incorporation of various
types of fasteners in one joint, unless they have
the same or similar mechanical properties.
4.5.2 It is not allowed to use different types of
adhesives in construction of a single element of
timber structure.
4.3
4.5.3 As an exception to paragraph 4.5.1, it is
allowed the use of nails and screws when
making glued joints, but only for tightening of
glued joint, and not as bearing fasteners.
4.3.1 Design of timber structures, shall be done
according to European Standards specified in
Appendix "F" of this Regulation.
114
Unified Construction Code of Republic of Kosovo
Chapter IV – Timber Structures
Section 2 – Structural
4.5.4 It is not allowed installation in timber
structures, of structural timber indicated in
Appendix "A" with water content greater than
22%.
foreseeable actions and impacts, and
calculation of certain parts of the timber
structure for all stages of transportation,
handling, execution and usage of building,
- Calculation of global stability of the structure,
3. In the program of quality control and quality
assurance of timber structures:
- Technical properties that construction
products must possess in order to be installed
in the timber structure, including adequate
information for labeling of construction
products, according to provisions of this
Regulation,
- Tests and procedures to prove the usability of
construction products that are manufactured at
the site for the purposes of that construction
site,
- Control of construction products incorporated
into the steel structure that has to be
conducted before their incorporation:
Test methods, for verification of load bearing
capacity and serviceability of timber structures,
including traditional fasteners and staples.
- Conditions for execution of works and other
requirements that must be fulfilled during the
execution of timber structure which affect the
attainment of the designed and specified
technical characteristics of timber structure and
fulfillment of essential requirement of that
building,
- Other conditions relevant for the fulfillment of
requirements laid down in this Regulation and
special regulations, and,
- Water content of elements of timber structure
before incorporation in timber structure and
water content of timber structure before
junction with the other parts of the building.
4.5.5 It is not allowed installation in timber
structures of timber elements that are not
protected by preventive care processes in a
manner to prevent re-wetting the timber during
transport, processing, intermediate storage,
assembly and use, avoiding direct contact with
the water and soil, proper stacking and covering
of timber elements.
4.6
4.6.1 Design documentation - a technical design
documentation of timber structure, which is an
integral part of the main project design of the
building shall include in particular:
1. in the technical description
- A description of the impacts from the purpose
and usage of building, and environmental
influence on the properties of the timber
structure,
- The data from the previous researches and
data from other surveys and studies that can
affect the properties of the timber structure,
- A description of a timber structure, including
foundation,
- A description of method for execution of
timber structure and installation of certain
construction products,
- Exposure class of timber structural parts,
including steel and concrete components,
- A description of the measures for structural
protection, measures for chemical protection
and special care if such is needed.
2. In the calculation of mechanical resistance
and stability
- Information on the predictable actions and
their impact on the structure of building,
- Information on the ground for foundation and
earthquake zone,
- Calculation of load bearing capacity and
serviceability of the timber structure for the
4.6.2 Requirements from item 3, paragraph
4.6.1, depending on conditions, procedures and
other circumstances of execution, may be
elaborated in more detail in the execution
project design documentation of the timber
structure.
115
Unified Construction Code of Republic of Kosovo
Chapter IV – Timber Structures
Section 2 – Structural
4.7
V. EXECUTION AND SERVICEABILITY OF TIMBER
STRUCTURES
4.7.1 In addition to conditions laid down in
paragraphs 4.1 to 4.6 of this Regulation, project
design of a timber structure in which the
execution of the timber structure is elaborated
must contain technical solutions for:
- Elements of the timber structure and ways of
their production or fabrication,
- Incorporation of elements into a timber
structure, including the calculation and required
properties of connections of the elements with
other elements of the timber structure,
- Transfer and transport of elements of a timber
structure (points of support and suspension and
description of lifting systems, position of
elements during transfer and transport,
transport path, and other), and the designed
weight and permitted weight tolerances of
elements of the timber structure,
- Arrangement of props, necessary supports
systems and other measures to ensure stability
and prevent damage to elements of the
structure during transport, incorporation and
connection of elements of the structure.
5.1
5.1.1 Execution of buildings that contain a
timber structure must be such that the timber
structure has technical characteristics and
fulfills other requirements laid down in this
Regulation, in accordance with the technical
solution of the building and conditions for
execution given in the project design, and so
that it ensures the preservation of such
properties and serviceability of the building
during its life.
5.1.2 When executing a timber structure,
contractor is obliged to follow the requirements
of project design of timber structure and
technical instructions for incorporation and
usage of construction products and comply with
the provisions of this Regulation.
5.2
5.2.1 When taking over a construction product
produced outside the construction site, the
contractor has to determine:
- Whether the construction product was
delivered with the mark in accordance with a
special regulation and if the data in the
documentation with which the construction
product was delivered match the data in the
mark,
- Whether the construction product was
delivered with technical instructions for
incorporation and use,
- Whether the properties, including the useful
life of the construction product and data
relevant for its incorporation, usage and impact
on properties and duration of a timber
structure are in accordance with properties and
data specified in the main project design.
4.8
4.8.1 In addition to conditions laid down in
paragraphs 4.1 to 4.6 of this Regulation, the
project design for reconstruction or renovation
of a building, in which the timber structure is
changed, must necessarily contain data on
determined
pre-existing
technical
characteristics of a timber structure
4.8.2 Pre-existing technical characteristics of a
timber structure shall be determined by
checking the documentation of the building,
tests, calculations and other appropriate ways.
5.2.2 The facts determined in accordance with
paragraph 5.2.1 shall be recorded in accordance
116
Unified Construction Code of Republic of Kosovo
Chapter IV – Timber Structures
Section 2 – Structural
with a special regulation on conducting daily
progress reports, whereas the documentation
with which the construction product was
delivered is saved among the proofs about the
conformity of construction products that the
contractor must have at the construction site.
technical characteristics and fulfills the
requirements laid down in the project design
and in this Regulation.
5.5.2 Conditions for execution of a timber
structure are specified with a program of
control and quality assurance that is an integral
part of the main project design of the timber
structure, at least in accordance with the
provisions of Appendix “G” of this Regulation.
5.3
5.3.1 Specified properties and usability of a
construction product produced at the
construction site are determined in the way
specified in the project design and in this
Regulation.
5.5.3 If the technical solution of a timber
structure and conditions in which execution
work is being performed and other
circumstances that could affect technical
characteristics of a timber structure are such
that they are not encompassed within the
provisions of Appendix “G” of this Regulation,
then in the program of control and quality
assurance, such special conditions of execution
must be specified which fulfill the requirements
of paragraph 5.5.1.
5.3.2 Data attesting the usability and attained
properties of the construction product from
paragraph 5.3.1 must be recorded by the
contractor in accordance with a special
regulation on conducting daily progress reports.
5.4
5.4.1 It is forbidden to incorporate a
construction product which:
- Is delivered without a mark in accordance with
a special regulation,
- Is delivered without technical instruction for
incorporation and use,
- Does not have the properties required by
project design or its useful life has expired, or
whose data relevant for incorporation, use and
impact on properties and durability of the
timber structure are not in accordance with the
data specified in the main project design.
5.5.4 Appendix “G” referred to in paragraphs
5.5.2 and 5.5.3 of this Article specifies in more
detail execution and maintenance of timber
structures.
5.6
5.6.1 It is considered that a timber structure has
the technical properties foreseen by the project
design and that it is usable if:
- Construction products are incorporated in a
timber structure in a specified way and have a
certificate of conformity according to paragraph
3.2.1 of this Regulation, or proofs of usability
according to paragraph 3.2.2 of this Regulation,
- Conditions of execution and other
circumstances which could affect the technical
characteristics of a timber structure are in
accordance with the requirements of project
design,
- The timber structure has proofs concerning
load-bearing capacity and serviceability
determined in examination by test load, when it
5.4.2 The incorporation of a construction
product, i.e., the continuation of work must be
allowed by supervising engineer, which is
recorded in accordance with a special
regulation on conducting daily progress reports.
5.5
5.5.1 Construction of a timber structure must
be such that the timber structure has the
117
Unified Construction Code of Republic of Kosovo
Chapter IV – Timber Structures
Section 2 – Structural
is prescribed as mandatory or required by
project design, and if for checking of these facts
exists formal records or documentation.
specified in the project design of the building
and in regulations in accordance with which the
timber structure was constructed are fulfilled.
5.6.2 It is considered that the serviceability of a
timber structure is proven if the conditions in
paragraph 5.6.1 and in paragraph 5.5 of this
Regulation have been fulfilled.
6.2
6.2.1 Maintenance of a timber structure
implies:
- Regular inspections of a timber structure, in
periods and in the way specified in the project
design of the building, this Regulation or a
special regulation passed in accordance with
the Construction Law,
-special inspections of a timber structure after
exceptional event or when an inspection body
requires it,
- conducting works in which the timber
structure remains in the condition, or is
returned to the condition specified in the
project design of the building and this
Regulation or a regulation in accordance with
which the timber structure was constructed.
5.7
5.7.1 If it is determined that the timber
structure does not possess properties foreseen
in its design, additional verification must be
carried out to prove that the timber
construction fulfills the requirements of this
Regulation.
5.7.2 Proof from paragraph 5.7.1 is considered a
part of the as build design.
5.7.3 In the case that it is confirmed that the
attained technical characteristics of the timber
structure do not fulfill the requirements of this
Regulation, it is necessary to produce project
design for rehabilitation of a timber structure.
6.2.2 Fulfillment of specified conditions for
maintenance of a timber structure is
documented in accordance with the
requirements of project design of the building
and:
- Reports on inspections and testing of a timber
structure,
- Records on maintenance work,
- In other suitable way, if not otherwise
specified in this Regulation or other regulation
passed in accordance with the provisions of
Construction Law.
VI. MAINTENANCE OF TIMBER STRUCTURES
6.1
6.1.1 Maintenance of a timber structure must
be such that during the life of the building its
technical characteristics remain preserved and
the requirements specified in the project design
of the building and in this Regulation are
fulfilled, as well as other essential requirements
that the building must fulfill in accordance with
a special regulation.
6.3
6.3.1 It is permitted to use for maintenance
works, only those construction products which
fulfill prescribed conditions and for which a
certificate of conformity is issued in accordance
with a special regulation, or for which usability
is proved in accordance with project design of
the building and this Regulation.
6.1.2 Maintenance of a timber structure that is
constructed in accordance with regulations that
were valid earlier must be such that during the
life of the building its technical characteristics
remain preserved and the requirements
118
Unified Construction Code of Republic of Kosovo
Chapter IV – Timber Structures
Section 2 – Structural
6.3.2 By the maintenance of the building or by
any other way the technical characteristics and
fulfillment of specified requirements for timber
structures must not be endangered.
6.4.1 While performing maintenance work on
timber structures, the provisions of this
Regulation that concern the execution of timber
structures apply.
6.4
119
Section 2 – Structural
Unified Construction Code of Republic of Kosovo
Chapter IV – Timber Structures
APPENDIX A
WOOD PRODUCTS
A.1 SCOPE
A.1.1 In this Appendix, in accordance with paragraph 3.3.1 of this Regulation, are specified technical
characteristics and other requirements for wood products that are integral parts of timber structures
and/or prefabricated elements from Appendix D to this Regulation, and the manner of certifying the
conformity of wood products unless specified differently in this Regulation.
A.1.2 Technical characteristics and other requirements and certifying of conformity of wood products
are determined or conducted in accordance with the standards stated in item A.6 of this Appendix,
standards to which those standards indicate and the provisions of this Appendix, and in accordance with
provisions of a special regulation.
A.1.3 Wood products, within the meaning of item A.1.1 of this Appendix, are products produced in a
production plant (factory) for such kind of a product, and encompass:
a) Solid timber (sawn and carpentry timber) set out in article A.2.1.5 subparagraph a) to b) of this
Regulation,
b) Glued laminated timber set out in article A.2.1.6 and structural products based on timber (ex. LVL)
c) wood-based panels set out in paragraph A.2.1.7, subparagraphs a) to g) of this Regulation.
A.2 SPECIFIC PROPERTIES, CERTIFICATION OF CONFORMITY AND MARKING
A.2.1 Specified properties
A.2.1.1 Technical properties of solid timber must fulfill general and special requirements essential for
the end purpose of solid timber and depending on the type of solid timber must be specified in
accordance with the standards of series SK EN 14081 or standards SK EN 14544, standard SK EN 385,
standards to which these standards indicate, as well as the provisions of this Annex.
A.2.1.2 Technical properties of structural products made of wood must fulfill general and special
requirements essential for the end purpose of structural products made of wood and depending on the
type of structural products made of wood must be specified in accordance with the standards of series
SK EN 14080 or standards SK EN 14374, standards to which these standards indicate, as well as the
provisions of this Annex.
A.2.1.3 Technical properties of wood-based panels must fulfill general and special requirements
essential for the end purpose of wood based panels and depending on the type of wood based panels
must be specified in accordance with the standards SK EN 13986, SK EN 14279 respectively SK EN 634-1,
standards to which these standards indicate, as well as the provisions of this Annex.
A.2.1.4 Technical properties of wood products must be specified in the project design of a timber
structure.
120
Section 2 – Structural
Unified Construction Code of Republic of Kosovo
Chapter IV – Timber Structures
A.2.1.4.1 Regardless of conditions of use of a timber structures, for solid timber, glued laminated timber
and structural products made of wood in the project design of timber structure must be specified
following properties:
a) Bending strength
b) Tensile strength
c) Modulus of elasticity
d) Bonding quality
e) Swelling and shrinking
f) Durability
A.2.1.4.2 Regardless of conditions of use of a timber structures, for wood based panels, in the project
design of timber structure must be specified following properties:
g) Characteristic values of strength perpendicular to surface (bending, shear, compression, tension)
h) Modulus of stiffness (perpendicular and parallel to surface)
i) Characteristic values of strength parallel to surface (bending, shear, compression, tension)
j) Density
k) Adhesives, percentage of adhesives and quality of internal bonding
l) Linear expansion (swelling)- for veneer panels linear expansion should be defined in both directions
m) Mechanical durability (hazard class)
n) Moisture content
A.2.1.4.3 For wooden based panels which correspond to class of serviceability 2 and 3, beside properties
specified in paragraph A.2.1.4.2 in project design of timber structure must be specified also
characteristics of water vapor permeability.
A.2.1.4.4 For wooden based panels intended for external use, beside properties specified in paragraph
A.2.1.4.2, in project design of timber structure must be specified also characteristics of thermal
conductivity.
A.2.1.4.5 For buildings that under a special regulation belong to the group of demanding buildings, for
all types of wood products in the project design of timber structures must be specified properties of fire
resistance.
A.2.1.4.6 In spaces where the release of formaldehyde could have an impact on health (residence spaces
for people, animal, spaces where food is stored etc.), for structural timber which is jointed with other
timber or is continued through adhesives (structural finger jointed solid timber), for beams and panels
based on wood, in project design of timber structure must be specified formaldehyde emission.
A.2.1.5 Structural timber is produced as
a) Structural timber with rectangular cross-section
b) Structural timber with round cross-section
A.2.1.6 Glued laminated timber and other wood based structural products (ex. LVL)
A.2.1.7 Wood based panels are produced as:
a) Solid wood panels (surface appearance hardwood or softwood)
121
Section 2 – Structural
Unified Construction Code of Republic of Kosovo
Chapter IV – Timber Structures
b) Glued laminated veneer panels (LVL) - panels with longitudinal veneers and panels with max. 20%
transverse orientation veneers.
c) Panels with crossover orientation of veneers.
d) Oriented Strand Boards (OSB)
e) Particleboards
f) Cement bonded particleboards
g) Fibreboards (hardboards, medium boards, soft boards, MDF medium density fibreboard)
A.2.2 Certification of conformity
.
A.2.2.1 Certification of conformity of structural timber from item A.2.1.5 of this Appendix depending on
the type of structural timber is conducted in accordance with the procedure and criteria of Appendix ZA
of series of standard SK EN 14081, or procedure and criteria of Appendix ZA of standard SK EN 14544,
and provisions of this Appendix and a special regulation.
A.2.2.2 Certification of conformity of laminated timber from item A.2.1.6 of this Appendix depending on
the type of laminated timber is conducted in accordance with the procedure and criteria of Appendix ZA
of standard SK EN 14080, or procedure and criteria of Appendix ZA of standard SK EN 14374, and
provisions of this Appendix and a special regulation.
A.2.2.3 Certification of conformity of wood-based panels from item A.2.1.7 of this Appendix depending
on the type of wood based panels is conducted in accordance with the procedure and criteria of
Appendix ZA of standard SK EN 13986, and provisions of this Appendix and a special regulation.
A.2.3 Marking
A.2.3.1 A timber product produced in accordance with a technical specification is marked on the bill of
lading and on a product in accordance with that specification. The mark must contain the reference to
that specification, in accordance with a special regulation.
A.3 TESTING
A.3.1 Taking of samples, preparation of samples and testing of wood products, depending on the type of
a product, is conducted in accordance with the standards to which the corresponding standard from
item A.6 refers.
A.3.2 Instead of testing according to item A.3.1 of this Appendix, for botanical type of woods and
country of origin determined by tables 1 and 2 of standard SK EN 1912, strength class can be determined
visually or by testing equipment according to standard SK EN 14081-1, and standards to which this
standard refers.
A.4 CONTROL BEFORE INCORPORATION
A.4.1 Timber product produced in accordance with technical specification for which the Conformity is
confirmed as laid down in this Appendix and the certificate of conformity is issued, may be incorporated
in the element of the timber structure if it conforms to the requirements from the project design of
timber structure.
122
Section 2 – Structural
Unified Construction Code of Republic of Kosovo
Chapter IV – Timber Structures
A.4.2 immediately before the incorporation of timber product appropriate supervisory activities must
be conducted as laid down in Annex H of this Regulation.
A.4.3 In case of suspicion on properties of wood products, before incorporation appropriate tests must
be conducted according to standards to which the corresponding standard from item A.6 refers.
A.5 MAINTAINING OF PROPERTIES
A.5.1 Producer and distributor of a timber product and the contractor employed are obliged to
undertake appropriate measures to maintain the properties of a timber product during handling,
transport, trans-shipment, storing and incorporation according to technical instructions of a producer.
A.6 LIST OF STANDARDS
A.6.1 Standards for structural timber
SK EN 14081-1:20XX
SK EN 14081-2:20XX
SK EN 14081-3:20XX
SK EN 14081-4:20XX
SK EN 14544:20XX
SK EN 385:20XX
Timber structures - Strength graded structural timber with rectangular
cross section - Part 1: General requirements
Timber structures - Strength graded structural timber with rectangular
cross section - Part 2: Machine grading - Additional requirements for
initial type testing
Timber structures - Strength graded structural timber with rectangular
cross section - Part 3: Machine grading- additional requirements for
factory production control
Timber structures - Strength graded structural timber with rectangular
cross section - Part 4: Machine grading - Grading machine settings for
machine controlled systems
Timber structures - Structural timber with round cross-section –
Requirements
Finger jointed structural timber. Performance requirements and
minimum production requirements
A.6.2 Standards for wood based load bearing elements
SK EN 14080:20XX
Timber structures. Glued laminated timber. Requirements
A.6.3 Standards for wood-based panels
SK EN 13986:20XX
SK EN 14279:20XX
SK EN 14374:20XX
SK EN 634-1:20XX
Wood-based panels for use in construction. Characteristics, evaluation
of conformity and marking
Laminated veneer lumber (LVL). Definitions, classification and
specifications
Timber structures. Structural laminated veneer lumber. Requirements
Cement-bonded particle boards. Specification. General requirements
123
Section 2 – Structural
Unified Construction Code of Republic of Kosovo
Chapter IV – Timber Structures
APPENDIX B
MECHANICAL FASTENERS
B.1 SCOPE
B.1.1 In this Appendix, in accordance with paragraph 3.3.1 of this Regulation, technical characteristics
and other requirements are specified for mechanical fasteners in timber structures, and the way of
certifying their conformity unless specified differently in this Regulation.
B.1.2 Technical characteristics and other requirements and certifying of conformity of mechanical
fasteners are determined or conducted in accordance with the standards stated in item B.6, standards
to which those standards indicate and the provisions of this Appendix, and in accordance with provisions
of a special regulation.
B.1.3 Mechanical fasteners, within the meaning of item B.1.1 of this Appendix, are dowel type fasteners
stated in item B.2.1.4, (a) to e)), of this Appendix and special performance connectors stated in item
B.2.1.5, a) to b), produced in a production plant (factory) for such kind of a product.
B.2 SPECIFIC PROPERTIES, CERTIFICATION OF CONFORMITY AND MARKING
B.2.1 Specified properties
B.2.1.1 Technical properties of dowel type fasteners must fulfill general and special requirements
essential for the end purpose of dowel type fasteners in timber structure and must be specified in
accordance with the standard SK EN 14592, standards to which this standard indicate, as well as the
provisions of this Appendix.
B.2.1.2 Technical properties of special performance connectors must fulfill general and special
requirements essential for the end purpose of special performance connectors in timber structure and
must be specified in accordance with the standards SK EN 14545and SK EN 912, standards to which
these standards indicate, as well as the provisions of this Appendix.
B.2.1.3 Technical properties of mechanical fasteners must be specified in the project design of timber
structure.
B.2.1.3.1 In the project design of timber structure must be specified corrosion protection depending on
the type of timber connector and classes of serviceability as outlined in Appendix E.
B.2.1.4 Types of dowel type fasteners are:
a)
b)
c)
d)
e)
nails
screws
dowels
bolts and nuts
staples
B.2.1.4 Types of connectors are:
124
Section 2 – Structural
Unified Construction Code of Republic of Kosovo
Chapter IV – Timber Structures
a) Punched metal plate fasteners
b) Timber fasteners
c) Nail plates
B.2.2 Certification of conformity
B.2.2.1 Certification of conformity of dowel type fasteners from item B.2.1.4 of this Appendix is
conducted in accordance with the procedure and criteria of Appendix ZA of standard SK EN 14592,
provisions of this Appendix and a special regulation.
B.2.2.2 Certification of conformity of connectors from item B.2.1.5 of this Appendix is conducted in
accordance with the procedure and criteria of Appendix ZA of standard SK EN 14545, criteria of standard
SK EN 912, provisions of this Appendix and a special regulation.
B.2.3 Marking
B.2.3.1 Mechanical fasteners produced in accordance with a technical specification are marked on the
bill of lading and on packaging in accordance with provisions of that specification. The mark must
contain the reference to that specification, in accordance with a special regulation.
B.3 TESTING
B.3.1 Taking of samples, preparation of samples and testing of mechanical fasteners, depending on a
kind of a timber connector, is conducted in accordance with standards to which the corresponding
standard from item B.6 refers.
B.4 CONTROL BEFORE INCORPORATION
B.4.1 Mechanical fasteners produced in accordance with standards in item B.6 of this Appendix for
which the conformity is confirmed in the way laid down in this Appendix and the certificate of
conformity is issued, may be incorporated in the timber structure or the elements of the timber
structure if they conform with the requirements of the project design of that timber structure.
B.4.2 Before the incorporation of mechanical fasteners appropriate supervisory activities are conducted
as laid down in Appendix H to this Regulation.
B.5 MAINTAINING OF PROPERTIES
B.5.1 The producer and distributor of mechanical fasteners and the contractor employed are obliged to
undertake appropriate measures to maintain the properties of a product during handling, transport,
trans-shipment, storing and incorporation according to technical instructions of a producer.
125
Section 2 – Structural
Unified Construction Code of Republic of Kosovo
Chapter IV – Timber Structures
B.6 LIST OF STANDARDS
B.6.1 Standards for dowel type fasteners
SK EN 14592:20XX
Timber structures. Dowel-type fasteners. Requirements
B.6.2 Standards for connectors
SK EN 14545:20XX
SK EN 912:20XX
Timber structures. Connectors. Requirements
Timber fasteners. Specifications for connectors for timbers
126
Section 2 – Structural
Unified Construction Code of Republic of Kosovo
Chapter IV – Timber Structures
APPENDIX C
ADHESIVES
C.1 SCOPE
C.1.1 In this Appendix, in accordance with paragraph 3.3.1 of this Regulation, technical characteristics
and other requirements are specified for adhesives used in timber structures, and the way of certifying
their conformity, unless specified differently in this Regulation.
C.1.2 Technical characteristics and other requirements and certifying of conformity of adhesives are
determined or conducted in accordance with the standards stated in item C.6, standards to which these
standards indicate and the provisions of this Appendix, and in accordance with provisions of a special
regulation
C.1.3 Adhesives, within the meaning of item C.1.1 of this Appendix, are stated in item C.2.1.8, (a) to b)),
of this Appendix produced in a production plant (factory).
C.2 SPECIFIC PROPERTIES, CERTIFICATION OF CONFORMITY AND MARKING
C.2.1 Specified properties
C.2.1.1 Technical properties of adhesives from item C.2.1.8.1, (a)), must fulfill general and special
requirements essential for the end purpose of adhesive and must be specified in accordance with
standard SK EN 301,and standards to which this standard indicates, as well as the provisions of this
Appendix.
C.2.1.2 Technical properties of adhesives from item C.2.1.8.1, (b)), must fulfill general and special
requirements essential for the end purpose of adhesive and must be specified in accordance with
standard SK EN 12436, and standards to which this standards indicates, as well as the provisions of this
Appendix.
C.2.1.3 Technical properties of adhesives from item C.2.1.8.1, (c)), must fulfill general and special
requirements essential for the end purpose of adhesive and must be specified in accordance with
standard SK EN 15425, and standards to which this standards indicates, as well as the provisions of this
Appendix.
C.2.1.4 Technical properties of adhesives from item C.2.1.8.2, (a)), must fulfill general and special
requirements essential for the end purpose of adhesive and must be specified in accordance with
standard SK EN 12765, and standards to which this standards indicates, as well as the provisions of this
Appendix.
C.2.1.5 Technical properties of adhesives from item C.2.1.8.2, (b)), must fulfill general and special
requirements essential for the end purpose of adhesive and must be specified in accordance with
standard SK EN 204, and standards to which this standards indicates, as well as the provisions of this
Appendix.
127
Section 2 – Structural
Unified Construction Code of Republic of Kosovo
Chapter IV – Timber Structures
C.2.1.6 Technical characteristics of adhesives determines contractor employed or manufacturer of
prefabricated elements in accordance with the requirements set out in project design or technical
specification , for timber structure or prefabricated element.
C.2.1.7 For casein adhesives except for the technical properties specified in standard SK EN 12436, it is
obligatory to test the resistance to delaminating and the resistance to the effects of wood.
C.2.1.8 According to intended purpose adhesives are categorized as:
a) Adhesives for load-bearing timber structures
b) Wood adhesives for non-structural application (formwork, partitions, fences, fill-in etc.)
C.2.1.8.1 Adhesives for load-bearing timber structures are:
a) Phenolic and amino plastic
b) Casein
c) One component polyurethane
C.2.1.8.2 Wood adhesives for non-structural application are:
a) Thermosetting (phenolic, amino- plastic, epoxy )
b) Thermoplastic
C.2.2 Certification of conformity
C.2.2.1 Certification of conformity of adhesives from item C.2.1.8 depending on type, is conducted in
accordance with the provisions from items C.2.2.1.1, C.2.2.1.2, C.2.2.1.3, C.2.2.1.4, C.2.2.1.5, provisions
of this Appendix and provisions of special regulation.
C.2.2.1.1 Certification of conformity of adhesives from item C.2.1.8.1, (a)) is conducted according to
standard SK EN 301, standards to which this standard indicate, by application of conformity systems 1, 3,
or 4 for properties related to requirements in case of fire and in accordance with provisions of a special
regulation, and conformity systems 2+ for all other properties.
C.2.2.1.2 Certification of conformity of adhesives from item C.2.1.8.1, (b)) is conducted according to
standard SK EN 12436, standards to which this standard indicate, by application of conformity systems
1, 3, or 4 for properties related to requirements in case of fire and in accordance with provisions of a
special regulation, and conformity systems 2+ for all other properties.
C.2.2.1.3 Certification of conformity of adhesives from item C.2.1.8.1, (c)) is conducted according to
standard SK EN 15425, standards to which this standard indicate, by application of conformity systems
1, 3, or 4 for properties related to requirements in case of fire and in accordance with provisions of a
special regulation, and conformity systems 2+ for all other properties.
C.2.2.1.4 Certification of conformity of adhesives from item C.2.1.7.2, (a)) is conducted according to
standard SK EN 12765 by application of conformity system 3.
128
Section 2 – Structural
Unified Construction Code of Republic of Kosovo
Chapter IV – Timber Structures
C.2.2.1.5 Certification of conformity of adhesives from item C.2.1.7.2, (b)) is conducted according to
standard SK EN 204 by application of conformity system 3.
C.2.3 Marking
C.2.3.1 Adhesive produced in accordance with technical specification, are marked on the bill of lading
and on packaging in accordance with provisions of those specifications. The mark must contain the
reference to that specification, in accordance with a special regulation.
C.3 TESTING
C.3.1 Taking of samples, preparation of samples and testing of adhesives, depending on type of
adhesive, is conducted in accordance with standards to which the corresponding standard from item C.6
of this Annex refers, for certain type of adhesive.
C.4 CONTROL BEFORE INCORPORATION
C.4.1 Adhesives produced in accordance with technical specification for which the conformity is
confirmed in the way laid down in this Appendix and a certificate of conformity is issued, may be
incorporated in the timber structure if they conform to the requirements of the contractor of timber
structure or manufacturer of prefabricated elements.
C.4.2 Before incorporation of adhesives it is necessary to make a visual check of color, viscosity,
appearance of sediments, presence of blobs etc.
C.4.3 Before the incorporation, appropriate supervisory activities are to be
Conducted as laid down in Appendix H to this Regulation
C.5 MAINTAINING OF PROPERTIES
C.5.1 The producer and distributor of adhesives and the contractor employed are obliged to undertake
appropriate measures to maintain the properties of a product during handling, transport, transshipment, storing and incorporation according to technical rules and instructions of a producer.
C.6 LIST OF STANDARDS
C.6.1 Standards for adhesives for load-bearing timber structures
SK EN 12436:20XX
SK EN 301:20XX
SK EN 15425:20XX
Adhesives for load-bearing timber structures. Casein adhesives.
Classification and performance requirements.
Adhesives, phenolic and amino plastic, for load-bearing timber
structures - Classification and performance requirements.
Adhesives: One component polyurethane for load bearing timber
structures. Classification and performance requirements
C.6.1 Standards for wood adhesives for non-structural application
129
Section 2 – Structural
Unified Construction Code of Republic of Kosovo
Chapter IV – Timber Structures
SK EN 12765:20XX
Classification of thermosetting wood adhesives for non-structural
applications
SK EN 204:20XX
Classification of thermoplastic wood adhesives for non-structural
applications
130
Section 2 – Structural
Unified Construction Code of Republic of Kosovo
Chapter IV – Timber Structures
APPENDIX D
PREFABRICATED ELEMENTS
D.1 SCOPE
D.1.1 In this Appendix, in accordance with paragraph 3.3.1 of this Regulation, technical characteristics
and other requirements are specified for prefabricated elements used in timber structures (hereinafter:
prefabricated elements), unless specified differently in this Regulation.
D.1.2 Prefabricated element within the meaning of item D.1.1 is the element produced or fabricated at
the place different from its final place in the structure, at a construction site for needs of that
construction site or in a production plant for production of prefabricated elements, from- timber
products produced in accordance with the Appendix A, fasteners produced in accordance with the
Appendix B, adhesives produced in accordance with the Appendix C, wood preservatives produced in
accordance with Appendix E and other products.
D.1.3 Technical characteristics and other requirements, verification of usability respectively certifying of
conformity of prefabricated elements are determined respectively conducted in accordance with item
D.1.3.1 and D.1.3.2 of this Appendix, and in accordance with provisions of a special regulation.
D.1.3.1 Technical characteristics and other requirements, and verification of usability of a prefabricated
element fabricated in accordance with a project design of a timber structure are determined and
conducted in accordance with that project design.
D.1.3.2 Technical characteristics and other requirements, and certifications of conformity of a
prefabricated element produced in accordance with technical specification (standard or technical
approval) are determined and conducted in accordance with that specification.
D.2 SPECIFIC PROPERTIES, CERTIFICATION OF CONFORMITY AND MARKING
D.2.1 Specified properties
D.2.1.1 Technical properties of prefabricated elements must fulfill general and special requirements
essential for the end purpose in the structure, and must be specified in accordance with the standard SK
EN 14732, and depending from type of prefabricated element also according to standards SK EN 14250
or SK EN 13377, standards to which these standards indicate, as well as the provisions of this Appendix.
D.2.1.2 Technical properties of timber products, fasteners, adhesives and preservatives of which the
prefabricated element is fabricated respectively produced must be specified in accordance with
Appendixes A, B, C, or E of this Regulation.
D.2.1.3 Technical properties of other products except those from paragraph D.2.1.2, of which the
prefabricated element is fabricated respectively produced must be specified in accordance with relevant
standards for those types of products.
D.2.1.4 Prefabricated element is fabricated or produced for:
131
Section 2 – Structural
Unified Construction Code of Republic of Kosovo
Chapter IV – Timber Structures
a) Structural use (element of a partially prefabricated timber structure, element of a prefabricated
timber structure or as a separate structure).
b) Non-structural use (formwork, partition, fence, infill).
D.2.1.5 Technical properties of prefabricated elements must be specified in a project design of a timber
structure, and in case of a prefabricated element produced in accordance with technical specification,
they shall be specified in the technical specification for that element.
D.2.2 Verification of usability and certification of conformity
D.2.2.1 Verification of usability of a prefabricated element fabricated in accordance with a project
design of a timber structure is conducted in accordance with the project design of a timber structure
and provisions of this Appendix, and includes the requirements for:
A) contractor’s fabrication control and testing of a prefabricated element, and
b) Supervision of a production plant and supervision of contractor’s fabrication control of manufacturing
of prefabricated element,
in the way appropriate for the attainment of technical characteristics of a timber structure in
accordance with this Regulation.
D.2.2.2 Certification of conformity of a prefabricated element produced in accordance with technical
specification is conducted in accordance with provisions of that specification, and provisions of this
Appendix also a special regulation.
D.2.3 Marking
D.2.3.1 Prefabricated element fabricated in accordance with the project design of a timber structure is
marked on a bill of lading and on the element itself in accordance with the mark from the project design.
D.2.3.2 Prefabricated element produced in accordance with a technical specification is marked on a bill
of lading and on the element itself in accordance with provisions of that specification. The mark must
contain the reference to that specification, in accordance with a special regulation.
D.3 TESTING
D.3.1 Prefabricated element fabricated in accordance with the project design of a timber structure is
tested in accordance with that project design.
D.3.2 Prefabricated element produced in accordance with technical specification is tested in accordance
with that specification.
D.4 DESIGN
D.4.1 Prefabricated element is designed in accordance with provisions of Appendix F respectively
Appendix G, and the provisions of this Regulation.
D.4.2 Design of a prefabricated element must prove technical characteristics and behavior in all phases
of the foreseen usage life of the element, i.e., for the phases of fabrication, transfer, storing, transport
to the construction site, incorporation, use, maintenance and disassembly.
132
Section 2 – Structural
Unified Construction Code of Republic of Kosovo
Chapter IV – Timber Structures
D.5 EXECUTION, FABRICATION AND PRODUCTION
D.5.1 When executing a timber structure with prefabricated elements the rules laid down in Appendix H
of this Regulation must be applied correspondingly, and:
- Details related to all phases of the foreseen usage life of elements,
- Details related to constituent materials of joints and standards that certify the conformity of those
materials,
- Details related to use and maintenance, specified in the design of a timber structure and/or technical
instruction for incorporation and use.
D.5.2 During fabrication of prefabricated element the provisions of Appendix H of this Regulation are
applied correspondingly.
D.5.3 when producing a prefabricated element the rules specified in corresponding technical
specification for that product must be followed.
D.6 CONTROL BEFORE INCORPORATION
D.6.1 Prefabricated element fabricated in accordance with a project design of a timber structure may be
incorporated in a timber structure if the conformity of timber products, fasteners, adhesives and
preservatives is certified and if the usability of a prefabricated element is proven in the way determined
in the project design of a timber structure and this Appendix.
D.6.2 Prefabricated element produced in accordance with technical specification for which the
conformity was certified in the way determined in this Appendix and the certificate of conformity was
issued, may be incorporated in a timber structure if it conforms with the requirements of the project
design of that timber structure.
D.6.3 Immediately before the incorporation of a prefabricated element appropriate supervisory
activities are conducted as laid down in Annex I of this Regulation.
D.7 LIST OF STANDARDS
D.7.1 Standards for prefabricated elements
Pr EN 14732:20XX
SK EN 14250:20XX
SK EN 13377:20XX
Timber structures: Prefabricated wall, floor and roof elements.
Requirements
Timber structures. Product requirements for prefabricated structural
members assembled with punched metal plate fasteners
Prefabricated timber formwork beams. Requirements, classification and
assessment
133
Section 2 – Structural
Unified Construction Code of Republic of Kosovo
Chapter IV – Timber Structures
APPENDIX E
PRESERVATION OF TIMBER STRUCTURES
E.1 SCOPE
E.1.1 In this Appendix, in accordance with Article 2.5 of this Regulation, are specified technical
characteristics and other requirements for preservation of timber structures and wooden preservatives,
and the way of certification of conformity of wooden preservatives, unless specified differently in this
Regulation.
E.1.2 Technical characteristics and other requirements for preservation of timber structures and
wooden preservatives, and certification of conformity of wooden preservatives are determined,
respectively conducted, depending on the type of preservation respectively wooden preservatives, in
accordance with provisions of this Appendix, standards to which it indicates and in accordance with
provisions of a special regulation.
E.1.3 Preservation of timber structure within the meaning of item E.1.1 includes building-physics,
structural, organizational and chemical measures of preservation from atmospheric actions, actions of
interior climate, seepage and other sources of water, also biological and fire actions in order to preserve
essential requirements of mechanical resistance and stability and fire resistance of timber structure.
E.2 TECHNICAL CHARACTERISTICS OF PRESERVATION OF WOODEN STRUCTURES
E.2.1 Technical characteristics of preservation of timber structures must be such that during service life
of the building through regulated respectively design determined execution and maintenance of
preservation of timber structure, it withstands all impacts of normal use of the building and impacts of
the environment, so that during its execution and use, foreseeable impacts on a building do not cause
losing of technical characteristics of timber structure.
E.2.2 Technical characteristics of preservation of timber structures must be such that, depending on the
class of exposure specified according to relevant provisions of series of standards SK EN 335, provide
equilibrium moisture content during service life of the building, with a provision that moisture content
insures protection against fungi, as a causative agent of decay, and enables dimensional stability,
without inducing by that permanent deformations.
E.2.3 Technical characteristics of preservation of timber structures regarding resistance to fire must be
harmonized with the requirements of special regulations, and at least with requirements of standards
indicated by Appendix “F” respectively Appendix “G” of this Regulation
E.2.4 Preservation of timber structure must encompass preservation of all components of timber
structure separately (wooden, metallic, etc), as well as preservation of timber structure as a whole.
E.2.5 By preservation of individual components of timber structure should not adversely affect other
components of structure.
E.2.6 Corrosion protection of metallic fasteners which form an integral part of timber structure is
conducted according to provisions of a special regulation, and in accordance with relevant provisions of
134
Section 2 – Structural
Unified Construction Code of Republic of Kosovo
Chapter IV – Timber Structures
standards SK EN 1992, SK EN 1993, also examples of minimal specification for protection against
corrosion of metal fasteners for different service classes given in standard SK EN 1995-1-1 table 4.1.
E.3 PRODUCTS FOR PRESERVATION OF TIMBER STRUCTURES
E.3.1 Specified properties, certification of conformity and marking
E.3.1.1 Specified properties
E.3.1.1.1 Technical properties of products for preservation must fulfill general and special requirements
essential for the end purpose of products for preservation and must be specified in accordance with the
standards stated in item E.6, standards to which these standards indicate, as well as the provisions of
this Appendix.
E.3.1.1.2 Types of products for preservation are:
a) agents for protection against abiotic causes of degradation ( atmospherics, hydrolysis, shrinking,
swelling, warping, surface discoloration caused by UV radiation, cracking and splitting, wear, abrasion ),
b) Agents for protection against biotic causes of degradation (insects; bacteria; fungi that cause mold,
decay and discoloration; marine borers),
c) Fire protection agents.
E.3.1.1.3 Technical characteristics of preservatives must be specified in project design of timber
structure.
E.3.1.1.4 For preservatives from E.3.1.1.2,(a)), technical characteristic of water-repellency must be
specified in project design of timber structure.
E.3.1.1.5 For preservatives from E.3.1.1.2,(b)), technical characteristic of effectiveness against actions of
biotic agents of degradation, must be specified in a project design of timber structure, for those biotic
agents of degradation which are, depending on the class of use defined in standard SK EN 335-1, occur
in timber structure.
E.3.1.1.6 For preservatives from E.3.1.1.2, (c)), technical characteristics of reaction to fire must be
specified in project design of timber structure, related to resistance to fire foreseen in project design for
timber structure.
E.3.1.2 Certification of conformity
E.3.1.2.1 Certification of conformity of preservatives from item E.3.1.1.2 is conducted depending on the
types of preservatives, in accordance with provisions of item E.3.1.2.1.1, item E.3.1.2.1.2, item
E.3.1.2.1.3, also provisions of this Appendix and a special regulation.
E.3.1.2.1.1 Certification of conformity of preservatives from item E.3.1.1.2,(a)), depending on the type of
preservative, is conducted for characteristics of preservatives against abiotic agents according to
reference standards from item E.6 by application of system of conformity attestation 4 according to
special regulation.
135
Section 2 – Structural
Unified Construction Code of Republic of Kosovo
Chapter IV – Timber Structures
E.3.1.2.1.2 Certification of conformity of preservatives from item E.3.1.1.2,(b)), depending on the type of
preservative, is conducted for characteristics of preservatives against biotic agents according to
reference standards from item E.6 by application of system of conformity attestation 3 according to
special regulation.
E.3.1.2.1.3 Certification of conformity of preservatives from item E.3.1.1.2,(c)), depending on the type of
preservative, is conducted for characteristics of fire protection according to relevant standards from
item E.6 by application of system of conformity attestation 1+ according to special regulation.
E.3.1.3 Marking of wooden preservatives
E.3.1.3.1Wooden preservatives, produced in accordance with relevant standards from item E.6, are
marked on the bill of lading and on packaging in accordance with provisions of those specifications. The
mark must contain the reference to that standard, in accordance with a special regulation.
E.3.2 Testing of wooden preservatives
E.3.2.1 Taking of samples, preparation of samples and testing of wooden preservatives from item
E.3.1.1.2, depending on their type, is conducted in accordance with relevant standards from item E.6
and standards to which these standards indicate.
E.3.3 Control of wooden preservatives before incorporation
E.3.3.1 Wooden preservative produced in accordance with technical specifications for which the
conformity is confirmed in the way laid down in this Appendix and the certificate of conformity is issued,
may be incorporated in a timber structure if they conform to the requirements of the project design of
that timber structure.
E.3.3.2 Before the incorporation of wooden preservative appropriate supervisory activities must be
conducted as laid down in Appendix H of this Regulation.
E.3.4 Maintaining properties
E.3.4.1 Producer and distributor of wooden preservatives and the contractor employed are obliged to
undertake appropriate measures to maintain the properties of a product during handling, transport,
trans-shipment, storing and incorporation according to technical rules and instructions of a producer.
E.4 DESIGN FOR PRESERVATION OF TIMBER STRUCTURES
E.4.1 Design, calculation and execution
E.4.1.1 For basis of design for preservation of timber structures in part of fire protection are applied
relevant standards from Appendix “F”, respectively Appendix “G” of this Regulation and standards to
which these standards indicate, unless specified differently in this Regulation.
136
Section 2 – Structural
Unified Construction Code of Republic of Kosovo
Chapter IV – Timber Structures
E.4.1.2 During design of preservation of timber structures, in a part of preservation from: weathering;
actions of interior climate; actions of seepage and other sources of water, and biological attacks;
provisions of items E.4.1.2.1, E.4.1.2.2, E.4.1.2.3 and E.4.1.2.4 of this Appendix must be applied
accordingly.
E.4.1.2.1 During design of building physics measures of preservation of timber structures in particular
must be paid attention to:
- Reduce to minimum possible degree impact of rainfall and damping of structural elements either from
environment or from other parts of that structure (ex. eaves, edges, lintels)
- Disable the contact of elements of the structure with the ground, earth, or other materials and media
that can cause excessive moisture (e.g. elevation of elements of the structure from the soil, sheathing
etc.)
- Long-term protection from weathering of those elements of timber structures that are exposed to
rainfall and also enabling their simple replacement.
- Allow as much air flow and easy access to elements of timber structures in order to perform regular
checkups.
E.4.1.2.2 During design of constructional measures of preservation of timber structures in particular
must be paid attention to:
- Ensure runoff of water from wooden surfaces and as short as possible water and snow retention on
exposed surfaces (surface treatment, rounding corners of beams, etc.)
- Prevent the penetration of rain water into the cross section (covering, coating, sealing, etc.)
- Allow as much as possible air flow and drying of all parts of structure.
E.4.1.2.3 During design of organizational measures of preservation of timber structures in particular
must be paid attention to:
- Providing such technical solutions that will during exploitation of the building, by permanent or
temporary ventilation prevent the timber structure to be exposed to the air with relative humidity
greater than 80% in indoor spaces.
- Determine method of repair of preservation of timber structures which (preservation) is damaged
during transport, processing, storing and assembly of the timber structure
- Determine, in accordance with a special regulation, requirements for the management of construction
waste generated by replaced parts of the structure during maintenance or removal of the structure.
E.4.1.2.4 During design of chemical measures of preservation of timber structures in particular must be
paid attention to:
- Prevention of surface degradation due to damping and solar radiation by application of surface
veneering.
- Determine the type and procedure for application of protective coating taking into account the type of
wood, purpose, class of exposure according to the relevant provisions of a series of standards SK EN 335,
aesthetics, durability according to the relevant provisions of standard SK EN 1995-1-1, SK EN 3501:20XX, SK EN 350-2:20XX, SK EN 460:20XX, SK ENV 1099:20XX and paragraphs C.3., C.4. and C.5. of
standard SK EN 14080, protection of the surface after the application, purpose, subsequent exposure to
wetting, impact of corrosion on metallic parts, impact on the environment, maintenance of the
structure, method of assembly, previous undertaken protection measures, emissions of formaldehyde,
etc.
137
Section 2 – Structural
Unified Construction Code of Republic of Kosovo
Chapter IV – Timber Structures
- Determine procedures for applying the final coat into elements of timber structure, when these
elements are preventively protected in the production plant, if it is provided by technical solution of
timber structure that the final coat will be applied on site.
E.4.1.3 During design of protective measures from items E.4.1.2.1, E.4.1.2.2, and E.4.1.2.4 it is necessary
give priority to building-physics and constructive measures of protection, while the chemical protective
measures apply:
- When by building-physics and constructive measures of preservation cannot be achieved the required
level of preservation.
- If climate and other conditions are particularly conducive to the development of biotic agents of
degradation (insects and fungi in humid and / or warmer climate attack more, which is also favored by
the proximity of the forest; microclimate, etc.)
E.4.1.4 During design of preservation of timber structures must be taken into account also possible
adverse effects of measures of preservation and / or preservatives on fulfilling technical characteristics
of timber structure from paragraph 2.1 of this Regulation.
E.4.2 Technical characteristics of wooden preservatives
E.4.2.1 Technical properties of construction products that are integral parts of preservation of timber
structure must be specified in the project design of timber structure according to provisions of item
E.3.1 of this Appendix.
E.5 EXECUTION OF PRESERVATION OF TIMBER STRUCTURES
E.5.1 Execution, supervisory activities and control procedures at a construction site
E.5.1.1 During transport, processing, storage, incorporation and use, it is necessary to prevent the
wetting of timber, avoiding direct contact with water or soil, proper stacking of elements and covering.
E.5.1.2 Elements of timber structures should be fold up in stacks that are covered, apart from each other
and exposed to constant ventilation. When stored in the open space, glued laminated timber intended
to be incorporated into the structure, must be embedded in structure in shortest possible time.
E.5.1.3 It is not permitted preventive preservation (impregnation) by application of chemical
preservatives at construction site.
E.5.1.4 The provision of item E.5.1.3 do not apply to the case of applying the final coats when this is
determined by project design of timber structure, also on repair of preservation which is necessary
because of eventual damage of protection during transport, processing, and assembly of elements of
the timber structure.
E.5.1.5 In the case of execution of works from item E.5.1.4 must be prevented the emission of hazardous
substances into the environment and implement adequate work protection measures.
E.5.1.7 Before applying pesticides is necessary to clean the surface of the structural element according
to the requirements of the project in accordance with the technical instructions.
138
Section 2 – Structural
Unified Construction Code of Republic of Kosovo
Chapter IV – Timber Structures
E.5.1.6 During application of preservative coating it is necessary to comply with all manufacturers’
instructions and requirements of the project design of timber structure.
E.5.1.7 Before application of preservative coatings it is necessary to clean the surface of the element of
the structure according to the requirements of project design and in accordance with the
manufacturer’s technical instructions.
E.5.1.8 For preservation of elements of the structure with glued joints it is not allowed application of
preservative coatings (veneers) which chemically react with the used glue.
E.5.1.9 During execution of timber structure should be managed, in accordance with requirements of a
special regulation, with the waste material of preservative coatings.
E.5.1.10 On construction site it is necessary to conduct appropriate supervisory activities and control
procedures in accordance with provisions of Appendix “G” of this Regulation.
E.5.2 Usability of preservation
E.5.2.1 During usability assessment of protection of timber structure must be taken into account:
a) Written records in the construction diary regarding characteristics and other data on the protection
of timber structures,
b) Proof of usability (test results, records of the implemented procedures, etc.) that the contractor
provides during implementation of procedures for protection of timber structure,
c) Execution conditions and other circumstances which according to construction diary and other
documentation that contractor must have at a construction site, also documentation that a
manufacturer of building products must have may influence the technical characteristics of the
protection of timber structures.
E.5.3 Subsequent assessment of characteristics of preservation treatment
E.5.3.1 For preservation treatment that does not have technical characteristics foreseen in project
design or the same cannot be affirmed due to lack of required documentation, technical characteristics
of protection of timber structure must be determined by subsequent testing and subsequent
calculations.
E.5.3.2 In order to determine the technical characteristics of protection treatment of timber structures
according to item E.5.3.1 of this Appendix, it is necessary to collect relevant information about the
protection treatment of timber structures and the circumstances of its execution to the extent and
degree that enable assessing the degree of compliance with the essential requirements of mechanical
resistance and stability , fire resistance and other essential requirements for the structure according to
provisions of special regulations.
139
Section 2 – Structural
Unified Construction Code of Republic of Kosovo
Chapter IV – Timber Structures
E.5.4 Maintenance of preservation treatment
E.5.4.1 Activities for maintenance of preservation treatment of timber structure must be conducted in
accordance with provisions of this Appendix and relevant standards from item E.6, as well as with
adequate application of provisions of other Appendixes of this Regulation.
E.5.4.2 Regular visual inspections for the purpose of maintenance of protection treatment of timber
structure are conducted in accordance with requirements specified in the project design of the
structure, or at least once a year.
E.5.4.3 Determination of condition of preservation treatment of timber structure in relation to designed
characteristics for the purpose of maintenance of protection treatment of timber structures must be
conducted at least every 5 years.
E.5.4.4. Methods of performing regular inspections in order to maintain the protection treatment of
timber structure is determined in project design of the structure, and includes at least:
a) visual inspection, which includes determination of the degree of damage of protection treatment as
well as eventual damages to timber structure that are essential for the preservation of technical
characteristics of protection treatment.
b) Determination of condition of protection treatment, if on the basis of visual inspection described in
sub-item a) are doubts on fulfilling of characteristics of protection treatment.
E.6 LIST OF STANDARDS
E.6.1 List of standards related to durability of wood
SK EN 335-1:20XX
SK EN 335-2:20XX
SK EN 335-3:20XX
SK EN 350-1:20XX
SK EN 350-2:20XX
SK EN 460:20XX
SK EN 14080:20XX
SK CEN/TS 1099:20XX
Durability of wood and wood-based products. Definitions of use classes.
General
Durability of wood and wood-based products. Definition of use classes.
Application to solid wood
Hazard classes of wood and wood-based products against biological
attack. Application to wood-based panels
Durability of wood and wood-based products. Natural durability of solid
wood. Guide to the principles of testing and classification of natural
durability of wood
Durability of wood and wood-based products. Natural durability of solid
wood. Guide to natural durability and treatability of selected wood
species of importance in Europe
Durability of wood and wood-based products. Natural durability of solid
wood. Guide to the durability requirements for wood to be used in
hazard classes
Timber structures. Glued laminated timber. Requirements
Plywood. Biological durability. Guidance for the assessment of plywood
for use in different use classes
140
Section 2 – Structural
Unified Construction Code of Republic of Kosovo
Chapter IV – Timber Structures
E.6.2 List of standards related to wood preservatives
SK EN 351-1:20XX
SK EN 599-1:20XX
SK EN 599-2:20XX
SK EN 15228:20XX
SK EN 927-1:20XX
SK EN 927-2:20XX
SK EN ISO 4618:20XX
SK EN 13501-1:20XX
SK EN 1995-1-2:20XX
Durability of wood and wood-based products. Preservative-treated solid
wood. Classification of preservative penetration and retention
Durability of wood and wood-based products. Efficacy of preventive
wood preservatives as determined by biological tests - Part 1:
Specification according to use class
Durability of wood and wood-based products. Performance of
preventive wood preservatives as determined by biological tests - Part
2: Classification and labelling
Structural timber. Structural timber preservative treated against
biological attack
Paints and varnishes - Coating materials and coating systems for
exterior wood - Part 1: Classification and selection
Paints and varnishes - Coating materials and coating systems for
exterior wood - Part 2: Performance specification
Paints and varnishes. Terms and definitions
E.6.3 List of standards related to fire protection
Fire classification of construction products and building elements.
Classification using test data from reaction to fire tests.
Eurocode 5: Design of timber structures - Part 1-2: General - Structural
fire design
141
Section 2 – Structural
Unified Construction Code of Republic of Kosovo
Chapter IV – Timber Structures
APPENDIX F
DESIGN OF TIMBER STRUCTURES
F.1 SCOPE
F.1.1 In this Appendix, in accordance with paragraph 4 of this Regulation, rules for designing of timber
structures of buildings are specified, unless specified differently in this Regulation.
F.1.2 The provisions of this Appendix refer to designing of timber structures of buildings considering also
basis of design and actions on structures, geotechnical design and design of structures resistant to
earthquakes.
F.2 DESIGN, CALCULATION AND EXECUTION
F.2.1 Rules for designing of timber structures are specified with Kosova/European standards in
sequences SK EN 1990, SK EN 1991, SK EN 1995, SK EN 1997 and SK EN 1998, with national features
given in nationally determined parameters within particular standards, and Kosova/European standards
indicated by these standards.
F.2.2 For basis of design and actions on timber structures, the Kosova/European standards in sequences
SK EN 1990, SK EN 1991 and SK EN 1995 apply, including the associated nationally determined
parameters, and standards indicated by standards in these sequences.
F.2.3 For design of timber structures related to earthquake resistance, the Kosova/European standards
in sequence SK EN 1998 apply, including the associated nationally determined parameters, and
standards indicated by standards in this sequence.
F.2.4 For design of timber structures, the Kosova/European standards in sequence
SK EN 1995
apply, including the associated nationally determined parameters, and standards indicated by standards
in this sequence.
F.2.5 For geotechnical design the Kosova/European standards in sequence SK EN 1997 apply, including
the associated nationally determined parameters, and standards indicated by standards in this sequence
F.2.6 If in accordance with paragraph 4.2.2 of this Regulation calculation of resistance to fire according
to SK EN 1995-1-2 is not conducted, a timber structure of a building designed in accordance with
provisions of this Appendix must satisfy general principles of protection from fire.
F.3 TECHNICAL PROPERTIES OF TIMBER PRODUCTS, MECHANICAL FASTENERS, ADHESIVES,
PREFABRICATED ELEMENTS
F.3.1 Technical properties of wood products are specified in the design of timber structures in
accordance with provisions of Appendix “A” of this Regulation
F.3.2 Technical properties of mechanical fasteners are specified in the design of timber structures in
accordance with provisions of Appendix “B” of this Regulation
142
Section 2 – Structural
Unified Construction Code of Republic of Kosovo
Chapter IV – Timber Structures
F.3.3 Technical properties of adhesives are specified in the design of timber structures in accordance
with provisions of Appendix “C” of this Regulation
F.3.4 Technical properties of prefabricated elements of structure are specified in the design of timber
structures in accordance with provisions of Appendix “D” of this Regulation
F.3.5 Technical properties of preservation of timber structure and wooden preservatives are specified in
the design of timber structures in accordance with provisions of Appendix “E” of this Regulation
F.4 LIST OF STANDARDS
F.4.1 Standards for design and calculation
Eurocode 0: Basis of Structural design
SK EN 1990:20XX:Eurocode 0. Basis of structural design.
Eurocode 1: Actions on Structures
SK EN 1991-1-1:20XX
Eurocode 1. Actions on structures. General actions. Densities,
self-weight, imposed loads for buildings.
SK EN 1991-1-2:20XX
Eurocode 1. Actions on structures. General actions.
Actions on structures exposed to fire.
SK EN 1991-1-3:20XX
Eurocode 1. Actions on structures. General actions. Snow Loads
SK EN 1991-1-4:20XX
Eurocode 1. Actions on structures. General actions. Wind
actions.
SK EN 1991-1-5:20XX
Eurocode 1. Actions on structures. General actions. Thermal
actions.
SK EN 1991-1-6:20XX
Eurocode 1. Actions on structures. General actions. Actions
during execution.
SK EN 1991-1-7:20XX
Eurocode 1. Actions on structures. General actions.
Accidental actions.
SK EN 1991-3:20XX
Eurocode 1. Actions on structures. Actions induced by cranes
and machines.
*(No National Annex published for any of SK EN 1991 series)
Eurocode 5: Design of timber structures
SK EN 1995-1-1:20XX
Eurocode 5: Design of timber structures - Part 1-1: General Common rules and rules for buildings
SK EN 1995-1-2:20XX
Eurocode 5: Design of timber structures - Part 1-2: General Structural fire design.
SK EN 1995-2:20XX
Eurocode 5: Design of timber structures - Part 2: Bridges
*(No National Annex published for any of SK EN 1995 series)
Eurocode 7: Geotechnical Design
143
Section 2 – Structural
Unified Construction Code of Republic of Kosovo
Chapter IV – Timber Structures
SK EN 1997-1:20XX
SK EN 1997-2:20XX
Eurocode 7. Geotechnical design. General rules
Eurocode 7. Geotechnical design. Ground investigation and
testing
*(No National Annex published for any of SK EN 1997 series)
Eurocode 8: Design of structures for earthquake resistance
SK EN 1998-1:20XX
Eurocode 8. Design of structures for earthquake resistance.
General rules, seismic actions and rules for buildings
SK EN 1998-2:20XX
Eurocode 8. Design of structures for earthquake resistance.
Bridges
SK EN 1998-3:20XX
Eurocode 8. Design of structures for earthquake resistance.
Assessment and retrofitting of buildings
SK EN 1998-4:20XX
Eurocode 8. Design of structures for earthquake resistance.
Silos, tanks and pipelines
SK EN 1998-5:20XX
Eurocode 8. Design of structures for earthquake resistance.
Foundations, retaining structures and geotechnical aspects
*(No National Annex published for any of SK EN 1998 series)
144
Section 2 – Structural
Unified Construction Code of Republic of Kosovo
Chapter IV – Timber Structures
APPENDIX G
EXECUTION AND MAINTENANCE OF TIMBER STRUCTURES
G.1 SCOPE
G.1.1 In this Appendix, in accordance with paragraph 5.5 of this Regulation, technical and other
requirements and conditions for execution of timber structures and supervisory activities and control
procedures in the execution of timber structures are specified, as well as maintenance of timber
structures, unless specified differently in this Regulation.
G.1.2 Technical and other requirements and conditions from item G.1.1 of this Appendix are
determined, i.e., execution and maintenance of timber structures is conducted in accordance with
standards from item G.4.1 and G.4.2 of this Appendix, standards indicated by these standards and
provisions of this Appendix and in accordance with provisions of a special regulation.
G.1.3 On execution and maintenance of timber structures are also applied the corresponding standards
for execution and maintenance of other kinds of products used in timber structures in accordance with
rules for those products, except those to which Appendixes A, B, C, D, and E of this Regulation refer.
G.2 EXECUTION, SUPERVISORY ACTIVITIES AND CONTROL PROCEDURES AT A CONSTRUCTION SITE
G.2.1 Execution
G.2.1.1 Elements of timber structures are constructed, from wooden products produced in accordance
with Appendix “A”, mechanical fasteners produced in accordance with Appendix “B”, adhesives
produced in accordance with Appendix “C”, wooden preservatives produced in accordance with
Appendix “E”, and from other products, or as prefabricated elements produced in accordance with
Appendix “D”, in accordance with the design of a timber structure and provisions of this Appendix.
G.2.1.2 Before assembly of elements of timber structure, contractor must:
- Inspect every bill of lading and marking of: wooden products, mechanical fasteners, adhesives,
wooden preservatives and other construction products, which will be used,
- Visual control of: wooden products, packaging of mechanical fasteners, adhesives, wooden
preservatives and packaging of other construction products to determine possible damage,
- Determine the moisture content of wood and prefabricated products.
G.2.1.3 Moisture content of wooden products shall be determined immediately prior to assembly of
elements of timber structure in accordance with the standards
SK EN 13183-1 and SK EN
13183-2.
G.2.1.4 Prior to the commencement of work for assembly of elements of timber structure, control tests
of construction products must be conducted in case of suspicion.
G.2.1.5 Elements of timber structure must be marked with a direction of assemblage if it is not clear
from their shape.
145
Section 2 – Structural
Unified Construction Code of Republic of Kosovo
Chapter IV – Timber Structures
G.2.1.6 Elements of timber structure, products referred to in Appendixes "A", "B", "C" and "E" of this
Regulation and other products which are incorporated into the timber structure must be transported
and stored until the moment of assemblage, in a manner as is determined in the design of timber
structure and manufacturers technical instructions.
G.2.1.7 During transport to the construction site and at the construction site as well as during
incorporation it is necessary to comply with all requirements of the design of timber structure and
ensure that wooden products and prefabricated elements are not brought into the position which is
non-compliant with the design that could result in the exceeding stress in comparison to those during
service, loss of stability or rollover of element.
G.2.1.8 Tailoring of wooden products, by rule is conducted in covered and especially for that reason
prepared platform or table, on which structure is drawn with all the details and cambers in actual size
with the use of precision tools.
G.2.1.9 As an exception from item G.2.1.8 in a case of simple elements of timber structures (roof rafters,
etc) or elements of the timber structure that can be jointed during incorporation at the final position,
the platform for tailoring of timber products doesn’t need to have drawn on it the structure in its actual
size.
G.2.1.10 During tailoring of timber products, the remaining parts which will be incorporated must be
appropriately stored and labeled so that there is no confusion about the type and category of product.
G.2.1.11 In truss girders it is necessary to check the ends of individual elements of truss for bumps and
cracks and the elements that do not meet the criteria of incorporation to throw out.
G.2.1.12 Holes, slots and notches for fasteners must be performed with such precision so to ensure joint
properties determined by design.
G.2.1.13 It is considered that the criteria from item G.2.1.12 is fulfilled if holes for fasteners are
performed simultaneously on all elements of the same joint provisionally compounded in final position.
G.2.1.14 Embedment of fasteners shall be conducted in such temporary position of elements of
structure which ensures the completion of designed camber.
G.2.1.15 During execution, timber structure must be secured from actions during execution (including
actions from equipment used during execution or procedures of execution) as well as wind actions or
unfinished structure in accordance with the design of timber structure.
G.2.1.16 All temporary fixings and restraints must be provided in the timber structure until timber
structure is not constructed to that extent which allows their safe removal.
G.2.2 Gluing of timber joints
G.2.2.1 Gluing on construction site is permitted only under controlled conditions, in accordance with
technical instructions of manufacturer of adhesive, requirements from design of timber structure and
provisions of this Appendix.
146
Section 2 – Structural
Unified Construction Code of Republic of Kosovo
Chapter IV – Timber Structures
G.2.2.2 Gluing can be performed on elements whose surface is already prepared (dried, degreased, clear
from dust etc.) in accordance with the project design and technical instructions of manufacturer.
G.2.2.3 During execution of glued joints it is forbidden to repair uneven surfaces with the sandpaper.
G.2.2.4 During execution of glued joints, moisture content of timber elements in the place of joint must
be controlled just before bonding in accordance with the relevant standards from item G.4.1 of this
Appendix.
G.2.2.5 Maximum difference of moisture content of timber elements in the joint shall be not more than
2% compared to moisture content determined by design.
G.2.2.6 All joints must be executed with adhesives of same origin, as well as adhesive with which is
executed bonding of layers of timber in case of laminated timber.
G.2.2.7 Adhesive must be prepared and applied in the manner and in the timeframe determined by
manufacturer’s technical instruction.
G.2.2.8 Glued joints must be treated according to the technical instructions of the manufacturer.
G.2.2.9 pressing during gluing must be evenly distributed throughout the joint.
G.2.2.10 Pressing must be applied in accordance with the manufacturer's technical instructions and in
no case shall be less than 50 N/cm2.
G.2.2.11 Pressing time must match the characteristics of the used adhesive and microclimate conditions
in which the bonding is performed.
G.2.2.12 During bonding is not allowed moving of elements.
G.2.2.13 Control of glued joint and bond strength must be also done in bonded elements after
completion of bonding, which is done by examination of test samples made on same terms and
conditions as primary bonded structure or by taking test samples from primary structure by appropriate
application of standard series SK EN 15416 and of series SK EN 302 (1-4).
G.2.3 Assembly of elements of timber structure
G.2.3.3 General
G.2.3.1.1 Rules specified in item G.2.3.2 shall be applied accordingly to each part of timber structure
fabricated on construction site out of final position.
G.2.3.2 Installation of prefabricated element
G.2.3.2.1 Prefabricated elements fabricated or produced under the provisions of Appendix “D” of this
Regulation shall be mounted in timber structure according to design of timber structure and/or
technical instruction for installation and use of prefabricated elements and provisions of this Regulation.
147
Section 2 – Structural
Unified Construction Code of Republic of Kosovo
Chapter IV – Timber Structures
G.2.3.2.2 Handling, storage and preservation of prefabricated elements should be in accordance with
the requirements of design of timber structures, relevant technical specifications for that prefabricated
element and provisions of this Appendix.
G.2.3.2.3 Contractor shall, prior to the installation on timber structure, check whether fabricated or
produced prefabricated element (including the moisture content of the element determined at time of
installation) is in accordance with the requirements of design of timber structure, and whether the
handling and storage of prefabricated elements led to its damage, deformation or other changes that
would affect the technical properties of timber structure.
G.2.3.2.4 Supervising engineer just before the installation of prefabricated element in timber structure,
must:
a) Check whether for the prefabricated element, made according to design of timber structure, usability
has been assessed in accordance with design.
b) Check whether for the prefabricated element produced according to technical specification is issued
certificate of conformity and whether the prefabricated element complies with the requirements of the
project design of timber structure,
c) Check whether the prefabricated element is placed in accordance with the design of timber structure
and Appendix "D" of this Regulation, respectively with technical instructions for installation and use,
d) Document the findings of all carried out tests by record in construction diary.
G.2.4 Serviceability of timber structures
G.2.4.1 During prove of serviceability of timber structure should be taken into account:
a) Records in the construction diary on the properties and other information on construction products
embedded in the timber structure,
b) Results of supervision activities and control procedures which in accordance with this Regulation
must be conducted before incorporation of construction products in the timber structure,
c) Serviceability proof (test results, records of implemented procedures, etc.) which contractor has
provided during execution of timber structure
d) Results of examination with test load of timber structure or any of its part,
e) Conditions of execution and any other circumstances which according to construction diary and any
other documentation which contractor must keep in construction site, as well as documentation which
producer of construction product must have may influence technical properties of timber structure.
G.2.4.2 Examination by test load is conducted in order to evaluate the behavior of structure in relation
to designed assumptions. By test load are examined timber structures for which this test is foreseen in
design, if there is a suspicion and if it is specified by this Appendix.
G.2.4.3 Examination from item G.2.4.2 must be conducted according to design of timber structure,
appropriate application of standards from item G.4 of this Appendix and provisions of this Regulation.
G.2.4.5 Examination from item G.2.4.2 is obligatory to conduct for cantilevered structures projecting
more than 15 m, girder beams spanning more than 30m and arch structures with length of arch more
than 60m.
148
Section 2 – Structural
Unified Construction Code of Republic of Kosovo
Chapter IV – Timber Structures
G.2.5 Subsequent prove of technical properties of timber structure
G.2.5.1 For timber structures that do not have the technical properties foreseen in design or the same
cannot be identified due to lack of required documentation, must by subsequent examination and
subsequent calculations determine technical properties of timber structure.
G.2.5.2 In order to determine technical properties of timber structure according to item G.2.5.1 of this
Appendix, it is necessary to collect relevant information’s of timber structure to that extent and degree
that allows assessment of the degree of compliance with the essential requirements of mechanical
resistance and stability, fire resistance and other essential requirements for the building according to
provisions of special regulations.
G.3 MAINTENANCE OF TIMBER STRUCTURES
G.3.1 Actions within the maintenance of timber structures must be conducted according to provisions of
this Appendix and standards referred to in this Appendix, as well as with appropriate application of
other provisions of this Regulation.
G.3.2 Frequency of regular inspections in order to maintain a timber structure are carried out in
accordance with the requirements of design of timber structure, but not less then:
a) 6 months for persevered parts of timber structure that serve for drainage (gutters, etc), respectively
according to Appendix “E” of this Regulation
b) 1 year for the parts of timber structure which are exposed to frequent changes of moisture content.
c) 3 years for the parts of timber structure which are located in areas with difficult conditions of air flow.
d) 10 years for the parts of timber structure which are located in areas with good ventilation.
G.3.3 Methods of inspections are specified in design of timber structure, and include at least:
a) Visual inspection, which includes determination of position and size of crack formation or expansion
of biological attack (fungi and/or insects), as well as other damage relevant for maintaining of
mechanical resistance and stability of the building.
b) Determination of condition of preservative coating of elements of timber structures
c) Determination of value of deflection of the main structural elements of timber structure in case of
general actions, if based on the visual inspection described in subparagraph a) there is a suspicion in
fulfilling the essential requirement of mechanical resistance and stability of building.
d) Determination of moisture content
G.3.4 Documentation referred to in item G.3.2 and G.3.3 and also other documentation regarding
maintenance of timber structure shall be permanently kept by the owner of the building.
G.4 LIST OF STANDARDS
G.4.1 Standards for execution and maintenance
SK EN 1995-1-1:20XX
Eurocode 5: Design of timber structures - Part 1-1: General Common rules and rules for buildings
149
Section 2 – Structural
SK CEN/TS 12872:20XX
SK EN 13183-1:20XX
SK EN 13183-2:20XX
SK EN 594:20XX
SK EN 595:20XX
SK EN 596:20XX
SK EN 1195:20XX
SK EN 302-1:20XX
SK EN 302-2:20XX
SK EN 302-3:20XX
SK EN 302-4:20XX
SK EN 205:20XX
SK EN 15416-1:20XX
SK EN 15416-2:20XX
SK EN 15416-3:20XX
Unified Construction Code of Republic of Kosovo
Chapter IV – Timber Structures
Wood-based Panels - Guidance On The Use Of Load-bearing
Boards in Floors, Walls and Roofs
Moisture content of a piece of sawn timber. Determination by
oven dry method
Moisture content of a piece of sawn timber. Estimation by
electrical resistance method
Timber structures. Test methods. Racking strength and stiffness
of timber frame wall panels
Timber structures. Test methods. Test of trusses for the
determination of strength and deformation behavior.
Timber structures. Test methods. Soft body impact test of
timber framed walls
Timber structures. Test methods. Performance of structural
floor decking
Adhesives for load bearing timber structures. Test methods.
Determination of bond strength in longitudinal tensile shear
strength
Adhesives for load-bearing timber structures. Test methods.
Determination of resistance to delamination.
Adhesives for load-bearing timber structures. Test methods.
Determination of the effect of acid damage to wood fibers by
temperature and humidity cycling on the transverse tensile
strength
Adhesives for load-bearing timber structures. Test methods.
Determination of the effects of wood shrinkage on the shear
strength
Adhesives. Wood adhesives for non-structural applications.
Determination of tensile shear strength of lap joints
Adhesives for Load Bearing Timber Structures - Test Methods Part 1: Static Load Test of Single Bond line Specimens In
Compression Shear
Adhesives for load bearing timber structures other than
phenolic and amino plastic. Test methods. Static load test of
multiple bond line specimens in compression shear
Adhesives for Load Bearing Timber Structures Other than
Phenolic and amino plastic - Test Methods - Part 3: Creep
Deformation Test at Cyclic Climate Conditions with Specimens
Loaded in Bending Shear
150