SPECIFICATION
of MATERIALS AND WORKMANSHIP
required in the
GROUND FLOOR EXTENSION, INTERNAL ALTERATIONS
& LOFT CONVERSION
at
for
Project Number
May 2010
SPF BS
1.00 PRELIMINARIES
1.01
This specification is to be read with the Architect's drawings numbered 487.04A,
05A, 06B, 07B, 08A and the Structural Engineer's drawings numbered 10155 and
these drawings will form part of the contract.
1.02
The Employer is
1.03
The Architect is
1.04
The Work consists of: 1) a Ground Floor Extension, 2) Internal alterations to both
Ground and First Floors and 3) a Loft Conversion.
1.05
The contractor shall have access to that part of the garden necessary to carry out
the work. Care must be taken to cause as little damage to the rest of the garden
and as little inconvenience to the occupants as is possible. Connections to the
existing accommodation shall be left as late as possible and shall be made at a
time mutually convenient to the Contractor and to the occupants. Use of the
garage space will be required by the occupants.
1.06
Vehicular access to the site will be only via
1.07
The Contractor will be responsible for making all necessary arrangements for
access with the Local Authority and or adjoining owners.
1.08
The works embraced in this Contract shall be carried out in accordance with the
printed Agreement for Minor Building Works 2005, issued under the sanction of
the Joint Contracts Tribunal all of which conditions are held to be incorporated in
and to form part of the Contract, subject however to the undernoted alterations,
modifications and supplementary clauses.
1.09
Clauses in the Conditions of Contract shall be completed or modified as follows:
Clause 2.2 Dates for commencement and completion to be agreed.
Clause 2.8 Liquidated Damages for non-completion to be £250.00per week.
Clause 2.10 Defects Liability Period shall be six months.
Clause 3.6 Work is to be carried out by sub-contractors nominated by
the Architect where and if indicated in the Specification. These items will be
subject to the normal discounts and the Contractor should allow for any
further profit required.
Clause 4.2 For the purposes of the Statutory Tax Deduction scheme the
Employer is not a “Contractor.”
Clause 4.3 Percentage of Certified Value retained to be 5%.
Clause 4.5 Half of Retention Fund to be released on Practical Completion.
Clause 4.8.1 Documentation to be supplied within six months.
Clause 4.11 Clause 4.11 shall be deleted.
Clause 5.3.2 Contractor‟s Insurance cover for injury or damage to property
Page - 1
SPF BS
etc to be not less than £5,000,000:00.
Clause 5.4A Clause 5.4A shall apply.
Clause 5.4B Clause 5.4B shall be deleted.
Clause 6.6 Clause 6.6 shall be deleted.
1.10
The Contractor shall be deemed to have visited and inspected the site and
existing buildings and to have examined the drawings and contract documents
before pricing and to have adequately acquainted himself with the local
conditions, accessibility of the works, the nature of the ground and sub-soil, the
availability and supply of materials, water, electricity and telephones and no claim
of want of knowledge in such respects will be entertained.
1.11
The materials and workmanship shall be to the reasonable satisfaction of the
Architect and shall be the best of their respective kinds. Materials and
workmanship shall comply where applicable with the current British Standard or
British Standard Code of Practice and the latest edition of the Technical
Requirements for the Design and Construction of Dwellings published by the
N.H.B.C.
BS 8000-1
BS 8000-2
BS 8000-2.1
BS 8000-2.2
BS 8000-3
BS 8000-4
BS 8000-5
:1989
BS 8000-6
BS 8000-7
BS 8000-8
BS 8000-9
:1997
:1990
:1994
:1999
:1990
:1990
:2001
:1989
:1990
BS 8000-10 :1995
BS 8000-11
BS 8000-11.1:1995
BS 8000-11.2:1990
BS 8000-12 :1989
BS 8000-13 :1989
BS 8000-14 :1989
BS 8000-15 :1990
BS 8000-16 :1997
Code of practice for excavation and filling.
Code of practice for concrete work, comprising;
mixing and transporting concrete.
Site works with in-situ and pre-cast concrete.
Code of practice for masonry.
Code of practice for waterproofing.
Code of practice for carpentry, joinery, and general
fittings.
Code of practice for slating, tiling roofs, and claddings.
Code of practice for glazing.
Code of practice for plasterboard partitions and dry linings.
Code of practice for cementitious levelling screeds and
wearing screeds.
Code of practice for plastering and rendering.
Code of practice for wall and floor tiling, comprising;
Ceramic tiles, terrazzo tiles, and mosaics.
Natural stone tiles.
Code of practice for decorative wall coverings and
painting.
Code of practice for above ground drainage and sanitary
applications.
Code of practice for below ground drainage.
Code of practice for hot and cold water services.
Code of practice for sealing joints in buildings using
sealants.
Page - 2
SPF BS
1.12
Water for the works must be clean and uncontaminated. If other than mains
supply is proposed evidence of suitability must be provided including testing to BS
3148:1980 if so instructed. The existing mains supply to the house may be used
provided this does not cause inconvenience to the occupiers.
1.13
The existing electric mains supply may be used, free of charge, provided this
does not cause inconvenience to the occupiers and such use is not excessive.
1.14
Existing Hedgerows, planters and trees to be preserved must be fenced before
building operations begin for protection.
1.15
Building materials intended for the works must be stored securely within the site
and in accordance with the manufacturer's recommendations. The location of
storage areas must be agreed with the occupants.
1.16
The Contractor must adequately safeguard the existing buildings affected by the
works from damage by the weather and theft. He must take all reasonable
precautions to prevent unauthorised access to the site, the works and adjoining
property.
1.17
The Contractor must take all reasonable precautions to prevent excessive noise
or other nuisance causing undue inconvenience to the occupants of the existing
buildings and adjoining property or the general public.
1.18
The Contractor shall protect all existing public and private roads, footpaths, kerbs
and other works from damage arising from the works. From time to time and
when so requested, all roads and paved areas used must be thoroughly cleaned
of mud and other debris and on completion must be left in a condition and state of
repair equal to that prevailing at the commencement of the work.
1.19
The Contractor's sign board and any other advertisement shall only be displayed
with the approval of the Employer and Architect.
1.20
A competent foreman is to be placed in charge of the site and he is to be in
attendance during all working hours.
1.21
The Contractor must ensure that operatives employed are appropriately skilled
and experienced for the type and quality of work undertaken.
1.22
The Contractor will need to provide Architect with Method and Risk Statements for
the works to be undertaken, prior to commencement of any on-site operations.
1.23
If the Contractor for any reason deems it necessary to execute works outside
normal working hours he shall obtain the consent of the Employer and the
Architect before doing so.
1.24
The Contractor shall carry out everything necessary for the proper execution and
completion of the works, whether or not shown or described, provided the same
may be reasonably inferred from the drawings or this specification.
Page - 3
SPF BS
1.25
The Contractor is responsible for setting out the works, taking site dimensions and
checking the dimensions on drawings etc. Any discrepancies and inconsistencies
are to be immediately notified to the Architect.
1.26
For the duration of the contract the Contractor is responsible for the health and
safety of those working on the building site and those with authorised entry to it.
He must comply with all relevant regulations in this respect.
1.27
The Contractor must give any notices required by the Local Authority and water,
electricity, gas or telephone companies.
1.28
The Contractor is responsible for providing any temporary buildings for the
accommodation of materials and site operatives. The Contractor must provide
temporary sanitary accommodation for site operatives. Sanitary accommodation
within the existing building may be used provided the minimum inconvenience is
caused to the occupants and only following employer‟s confirmation of
acceptance over the pre-contract meeting.
1.29
The Contractor shall provide a mobile telephone service to the site for the
duration of the contract and pay all charges in connection with it.
1.30
The Contractor must protect the works from adverse weather conditions including
rain and frost and from damage by subsequent operations.
1.31
The Contractor shall allow for the general attendance of trades on each other.
1.32
The Contractor must report any defects in the existing construction to the
Architect without delay. He must obtain instructions before proceeding with work
which may cover up or otherwise hinder access to the defective construction or be
rendered abortive by the carrying out of remedial work.
1.33
The Contractor must provide all plant tools, scaffolding and the like necessary for
the purpose of proper execution of the works and their inspection by the Architect
or Engineer.
1.34
The Contractor shall remove all debris from the site as it accumulates and on
completion remove all temporary buildings, plant and surplus materials, clean all
glass outside and in and generally leave all clean and tidy.
1.35
At the completion of the Contract the Contractor must provide the Employer with a
certificate indicating that the building carries the 10 year warranty of the National
House Building Council. The Contractor must arrange for all inspections and pay
all charges required by the N.H.B.C.
1.36
Include the sum of £4,000.00 for contingencies to be used as directed by the
Architect and deducted in whole or in part if not required.
Page - 4
SPF BS
2.00 DEMOLITION
2.01
All demolition work shall be carried out by an approved specialist demolition
contractor who must be a member of the National Federation of Demolition
Contractors and provide evidence of insurance cover equivalent to the
requirements of the Conditions of Contract.
2.02
Pulling down is to be carried out in such a manner as to cause as little
inconvenience as possible to the occupants of the existing building, to adjoining
owners, or to the public and the Contractor will be held responsible for any claims
which may arise from disregard of this clause. Debris is to be kept well watered
during the work to prevent dust arising.
2.03
The Contractor must design and supply all shoring, needling and strutting, or
other supports to walls, floors, roofs etc., necessary for the protection and safety
of existing buildings and all fans, screens and other protection necessary to
protect adjoining owners and the general public.
2.04
The Contractor shall alter, adapt and maintain all such temporary works as may
be necessary from time to time and finally clear away and make good all
disturbance. He will be held solely responsible for the safety of existing buildings
on or adjacent to the site and temporary works, and the making good of all
damage done.
2.05
Sound old bricks arising from the pulling down, if cleaned and approved by the
Architect, may be reused in making up. Brick rubbish or other approved hard
materials arising from the pulling down, may be used in making up levels under
floors etc. All other materials not described to be re-fixed or stored and all rubbish
and debris are to be removed from the site.
2.06
No rubbish or material to be discarded shall be burned on site.
2.07
Materials arising from the demolitions must not be stacked or allowed to
accumulate on existing structures in such a way as to endanger their stability.
The Contractor will be held entirely responsible for damage arising from this
cause.
2.08
The Contractor shall be responsible for locating all existing services affected by
the demolitions and arranging for their disconnection or diversion so that they may
be entirely self-contained within the parts of the premises which are to remain.
The Contractor shall give notices to water, gas, telephone and electricity
companies and allow facilities for removing any fixtures, fittings or services which
may belong to them and pay any charges arising.
Page - 5
SPF BS
3.00 EXCAVATION AND GROUNDWORK
3.01
The contractor is advised to visit the site and satisfy himself as to the nature of the
ground to be excavated, his prices will be deemed to include for excavating in any
type of ground including "made ground" or granular material filling but excepting
running sand, old foundations and rock (rock shall be defined as naturally
occurring stone which, in the opinion of both parties to the Contract, can only be
removed by the use of explosives, compressor tools or hammers and wedges;
materials which can be excavated by means of mechanical excavators will be
deemed not to be rock); and must include for breaking out or grubbing up and
carting away any old tree roots etc., and breaking out and sealing off old drains,
which may be encountered. No allowances will be made due to the failure of the
Contractor to satisfy himself on these matters.
3.02
If loose or soft ground is met with, the Contractor shall excavate the same to a
solid foundation and shall fill up the excavation with concrete, granular material or
earth as the Architect directs. Such extra excavation and filling will be paid for at
Schedule Rates.
3.03
In the event of the Contractor excavating below the proper level in good ground
and as shown on the Drawings or excavating "battered" sides to trenches or if
excavation side slips occur for whatever the reason he shall remove any debris
and fill up the part so excavated or fallen with concrete, granular material or earth,
as the Architect directs, at his own expense.
3.04
The responsibility for draining away, pumping and otherwise removing water will
rest with the Contractor throughout the duration of the Contract. The methods
employed shall, in all cases, be to the satisfaction of the Architect, and if water is
removed by pumping, it shall be done so that the material in or around the
excavation will not be disturbed by the pumping, and adequate sumps shall be
provided.
If water is pumped into a sewer the Contractor shall be responsible for any
damage caused or any expense in removing from such sewer deposits caused by
his work. The Contractor is not to employ continuous pumping methods which
could withdraw water from foundations of adjoining buildings.
3.05
The Contractor is to give notice to the Local Authority and the Architect when the
excavations are ready to receive concrete, and obtain approval that a secure
foundation has been reached.
3.06
The Contractor is to take all necessary precautions to prevent damage to existing
trees and hedgerows during excavations either by physical damage to roots or by
altering ground levels around them.
3.07
The Contractor is responsible for locating all existing services and avoiding
damage to and supporting them during excavation. Should any such damage
occur the appropriate companies must be notified and the damage made good at
the Contractors expense.
Page - 6
SPF BS
3.08
The area of the site to be covered by new building is to be stripped of all top soil
and vegetable matter to a depth of not less than 150 mm or any greater depth
found necessary on site.
3.09
All excavated material not required, or not suitable for backfilling is to be removed
from the site.
3.10
Any coins, antiquities or other objects of interest found whilst excavating are the
property of the Employer and must be handed over to the Architect.
3.11
All re-filling of excavated material next to the foundations and in the trenches is to
be done in layers not exceeding 225 mm thick. Each layer is to be compacted
before the next is placed. Back filling in drain and service trenches must be
carried out in accordance with the drain manufacturer's recommendations and the
requirements of the appropriate Authorities.
3.12
Hardcore is to consist of clean, hard, dry, broken stone or other suitable approved
material, free from dust and foreign matter, broken to pass a 75 mm sieve,
thoroughly rammed and consolidated in layers not exceeding 150 mm. The
specified thickness is to be the finished thickness after compaction with a roller.
The top surface of hardcore is to be blinded with a minimum thickness of 25 mm
sand or other approved material, and finished to exact levels to form a clean and
solid formation.
3.13
All existing plants and paving affected by the excavations for New Extension are
to be carefully removed prior to work commencing, stored while the work is
carried out and reinstated on completion.
Page - 7
SPF BS
4.00 CONCRETE WORK
4.01
The cement shall be Ordinary Portland Cement to BS 12:1996 stored in a dry
place not in contact with the ground.
4.02
Course and fine aggregates for concrete work shall be in accordance with BS
882:1992.
4.03
Constituent materials for concrete shall be in accordance with BS 5328-1:1997,
BS 5328-2:1997, BS 5328-3:1990 Admixtures must not be used unless specified
or approved.
4.04
Water for concrete is to be clean and uncontaminated. Approval must be
obtained if other than mains supply is proposed and in this case testing to BS
3148:1980 may be required.
4.05
It is the Contractor's responsibility to select a suitable concrete mix for each part
of the work strictly in accordance with the requirements of BS 5328:1990 Parts 1
and 2 and NHBC regulations.
4.06
Unless otherwise specified the concrete mix shall be selected from the following
table and in accordance with BS 5328:1990.
USE
GENERAL PURPOSE CONCRETE MIX
Substructure
Dry Ground
Rough Binding
Strip Foundations
Trench Fill
Other mass concrete
C7.5P
C7.5P
House and garage ground
floor slabs fully or
nominally reinforced
C20P
Fill to wall cavities
Solid filling under steps
C10P
C10P
C10P
C7.5P
C7.5P
C10P
C10P
C10P
Superstructure
Mild
General Reinforced Concrete C20P
4.07
Wet and Poor Ground
Exposure
Moderate Severe
C25P
C30P
Unless otherwise specified concrete mix portions shall be as follows:
Fully or nominally reinforced concrete not exposed to the weather,per50
kg bag of cement;
115 kg Fine Aggregate
195 kg Course Aggregate
4.08
Ready mixed concrete may be used provided it complies with this specification
and BS 5328:1997, and it is supplied by a British Ready Mixed Concrete
Association Approved Depot and delivery notes are retained for inspection. The
3
minimum cement content of designed mixes shall be 220 kg/m . Designed mixes
for reinforced concrete shall comply with the requirements of BS 8110-1:1997.
Page - 8
SPF BS
4.09
Extra water must not be added to ready mixed concrete.
4.10
Where sulphates are present in the ground water, the ground or any adjacent
material, the level of sulphates shall be determined and concrete mixes designed
appropriately to resist sulphate attack.
4.11
Site mixed concrete shall be placed within 30 minutes. Ready mixed concrete
shall be placed within 2 hours of water being added to the cement.
4.12
All concrete must be thoroughly compacted for its full depth by mechanical
vibration unless otherwise approved.
4.13
Concrete must not be placed against frozen or frost covered surfaces or when the
o
air temperature is less than 5 C
4.14
Concrete shall be covered and protected from excessive heat or cold, rain,
physical damage and movement for a period of seven days after placing. During
dry weather the surface of the concrete shall be kept damp by watering through a
rose for a period of seven days after laying.
4.15
Lay under all new solid floor slabs a membrane of 1200 gauge polythene sheet to
BS 3012. Laps are not to be less than 150 mm formed into a welt (lapped and
turned over). At the edges of the floor the membrane is to be turned up to and
lapped with the D.P.C. in all walls..
4.16
The insulation for concrete floors in contact with the ground is to be 100mm
„CELOTEX‟ GA3000 or similar Insulation laid over Concrete Slab. A suitable
Vapour Control Layer to manufacturer‟s recommendation to be laid over
Insulation (under screed). Edge insulation of 20 mm thick „CELOTEX‟ TB3000
up-stand to be provided at all perimeters to the combined full depth of the screed
and insulation and lapped into wall dpc. No chasing of the insulation layer for
services will be permitted without the prior consent of the Architect.
4.17
The mild steel reinforcement shall conform in all respects with BS 4449:1997,
and shall be clean and free from dirt, oil, paint, loose rust or scale or other harmful
matter immediately before placing concrete.
Bends hooks and cranks shall conform to BS 8666:2000, and BS EN ISO
4066:2000. Laps and splices shall be in accordance with BS 8110:1997 and all
fabric reinforcement shall be side lapped one complete mesh. The steel shall be
accurately fixed in position with bars securely wired together with No 16 gauge
soft iron wire wherever necessary to prevent displacement during concreting.
Specified cover of concrete shall be maintained by the use of approved spacing
devices which shall remain in the concrete after use.
Page - 9
SPF BS
4.18
All formwork shall be erected true to line, level and profile and shall be of
sufficient strength to withstand displacement or distortion by the weight, placing
and vibration of the concrete or loss of water. Wrought formwork shall comprise
either wrought timber or rough finished timber lined with 10 mm thick plywood
treated with 'Phenolic' resin or other approved material to produce clean, true and
smooth surfaces free from shutter marks with true and well defined arises.
4.19
If a necessity arises for use of concrete lintels, Contractor to contact Architect for
exact specification to be provided.
Page - 10
SPF BS
5.00
STRUCTURAL STEELWORK
5.01
Hot rolled steel sections except angles to be to BS 4, Part 1, 1980, made from
steel to BS 4360.
5.02
Hot rolled steel equal and unequal angles shall be to BS 4848, Part 4, 1972,
made from steel to BS 4360.
5.03
Bolts, screws and nuts shall be to BS 4190 or BS 3692.
5.04
Washers shall be to BS 4320
5.05
Steel shall be blast cleaned in accordance with BS 4232.
5.06
Fabrication and erection shall be in accordance with BS 449, Part 2. All
connections are designed by Structural Engineer to safely support the loads,
reactions and bending moments imposed on the structure. Engineer‟s drawings,
details and calculations to be strictly followed by Contractor. Holes shall be drilled,
not punched and have all burrs removed. Bolt clearances shall have the
tolerances indicated on the drawings.
5.07
All steelwork shall be prepared by removing all scale and rust, cleaned free from
grease and dirt. Steelwork to be delivered on site painted with one coat red oxide
primer.
5.08
Steelwork must not be stacked or handled before or during erection in such a way
as would cause undue stress to the members or joints or damage to priming.
5.09
The Contractor must ensure that all steelwork installed is accurately lined, levelled
and plumbed in accordance with the Engineer's drawings.
5.10
Lintels to openings in all walls shall be obtained from Catnic Lintels Limited, of
types indicated on Architect‟s drawings, correctly sized for the span of the
opening, with 150 mm minimum bearing at each end and d.p.c. over all in
accordance with the manufacturer's recommendations. All Lintels to have a three
course blue brick pad-stone under bearing.
Page - 11
SPF BS
6.00 BRICKWORK AND BLOCKWORK
6.01
Facing bricks shall be 215 x 102,5 x 65 mm FL quality to match the existing in
colour, surface texture and size - to comply with BS 3921:1995, and the
manufacturer's specification, hard, square, sound, free from cracks and defects
and even in size.
6.02
Semi-Engineering bricks for use below d.p.c. shall be 65 mm red, pressed
engineering bricks to BS 3921-2:1995, Table 6, Class B and obtained from an
approved manufacturer.
6.03
Building blocks for the inner leaf of cavity walls shall be 100 mm thick heavyweight concrete blocks (density 1800Kg/cub.m.) to comply with BS 6073:1981.
6.04
Building blocks for internal partitions shall be 100 mm thick heavy-weight concrete
blocks (density 1800Kg/cub.m.) to comply with BS 6073:1981.
6.05
Components for mortar shall be in accordance with BS 5628:2001 Part 3.
6.06
Wall ties for cavity walls are to be of galvanised stainless steel, 200 mm long, to
BS 1143:1978, built in at 750 mm centres horizontally and 450 mm centres
vertically and staggered. Around openings ties shall be built in at 300 mm
centres.
6.07
The damp proof course shall be of a high performance pitch polymer system BS
2782: 1996 and BS 5628: 2001, on two courses of blue bricks and to extend
through the full thickness of all walls including pointing, with 100 mm overlap at
joints sealed with Hyload mastic. The d.p.c. is to be at least 150 mm above
adjacent finished ground level and continuous with existing d.p.c.s and new and
existing d.p.m.s.
6.08
Cavity wall insulation shall be 70 mm CELOTEX CW-3000 cavity wall panel
insulation built in as the work proceeds strictly in accordance with the
manufacturer's instructions. Insulation Panels must be tightly butted with no
mortar in the joints.
6.09
Cement mortar for use below d.p.c. shall be composed of one part by volume of
cement to three parts sand.
6.10
Cement lime mortar shall be composed of cement, lime and sand in the
proportions of one to one to six by volume.
6.11
Mortar mixes shall be selected in accordance with the brick or block
manufacturer's recommendations and BS 5628:2001.
6.12
Mortars containing cement should be used within two hours of mixing the cement
and mortar which has commenced to set must be discarded.
6.13
Workmanship shall generally be in accordance with BS 5628-32001 and
Page - 12
SPF BS
BS 8000-3:2001. All new brickwork and blockwork is to be set out and built to the
respective dimensions, thickness and heights shown on the drawings. No broken
or cut bricks or blocks are to be used except where required to maintain the bond.
Making out existing facework shall be in matching bond.
6.14
All bricklaying shall be suspended when the temperature is less than 2 degrees
Centigrade and completed brickwork shall be suitably protected from frost and
other harmful weather conditions.
6.15
No portion of brickwork is to rise more than 900 mm above adjacent work and if
temporarily stopped, it is to be stepped back at the angle appropriate to the bond.
6.16
All perpends are to be kept true, square and in facework plumb with the perpends
above and below, and the joints are to be of uniform thickness. The whole is to
be properly bonded and levelled around at floor level.
6.17
All brickwork is to rise four courses to 300 mm
6.18
All bricks are to be lightly wetted before use. Blocks are to be kept dry before
laying.
6.19
Bricks for faced brickwork shall be selected from the stack and distributed evenly
throughout the work so that no patches appear. Mix different deliveries which
vary in colour to avoid horizontal stripes. Faced brickwork shall be pointed with a
neat flush joint – to match existing as the work proceeds. The face of the
brickwork shall be kept free of mortar splashes etc. and protected from staining
by scaffolding, or any other cause.
6.20
The cavities of hollow walls are to be kept clear of rubbish and mortar droppings
by movable boards or other approved method.
6.21
The bottom of the cavity is to be filled with fine concrete to 150 mm below d.p.c.
level or ground level whichever is lower. Every fourth perpend at this level is to
be left open.
6.22
Where reveal are formed in cavity walls the wall is to be built solid across the
cavity and the outer skin is to be separated from the cavity filling by a d.p.c. fixed
so as to ensure the weather-proof qualities of the wall.
6.23
Cavities over openings are to be bridged by a flexible d.p.c. falling towards the
outer leaf, folded and cut so as to ensure the weather-proof qualities of the wall.
Open perpends shall be formed in the outer leaf above the d.p.c.
6.24
All door and window templates are to be built in as the work proceeds and to be
securely fixed to pallets of sound timber soaked in creosote, with long grain
exposed, bedded in mortar and pointed up. Build in pallets for internal linings for
doors etc., not less than 4 pallets at each side of opening.
Page - 13
SPF BS
6.25
Where new openings are formed or existing openings adapted, reveals and the
like are to be quoined up with new matching bricks or blocks as appropriate
properly bonded to match existing and cut ,toothed and bonded at the junction
with old work. Where making out face work is required following the filling of old
door and window openings or the like this shall also include the removal and
making out of the associated arches, lintels, cills, jambs and the like, unless
specified otherwise.
6.26
Repointing old facework shall include raking out joints of all loose mortar and
repointing in matching mortar in the same style of pointing. Any broken bricks, old
pipe fixings, cemented up holes etc. shall be cut out and new bricks inserted. Any
efflorescence, paint splashes, moss or other blemishes shall be removed by wire
brushing.
6.27
Where new brickwork or blockwork is built up to, or against, existing it shall be
properly toothed and bonded or connected by an approved stainless steel
connection plate used strictly in accordance with the manufacturer's
recommendations. In cavity walls old and new cavities shall be made continuous.
6.28
Generally allow for raking out for and repointing after all flashings, execute all
cutting and bonding around openings, build in pallets, sills and lintels and chimney
capping and padstones. Allow for filling between all joists and rafters. Cut holes
and chases for pipes, conduits etc and make good.
Page - 14
SPF BS
7.00 CARPENTRY AND JOINERY
7.01
All timber is to be well seasoned, free from large, loose and dead knots, decayed
or waney edges, splits and any other defects which would render it unsuitable for
its purpose.
7.02
Softwood for carpentry generally is to be in accordance with BS 4978:1996 and to
the grades specified on the drawing. The timber is to be seasoned to a moisture
content of or below the maximum values specified in BSCP 112: 1971 for its
position in the structure before fabrication.
7.03
Softwood for joinery unless otherwise specified is to be European Redwood,
European Whitewood, Douglas Fir or Western Hemlock and to conform to the
requirements of BS EN 942-1:1996 (replaces BS 1186 Part 1).
7.04
Hardwood of the species specified shall be of prime quality, kiln dried, free from
seasoning defects and of uniform colour and grain.
7.05
The moisture content of the timber for joinery when it is manufactured and
delivered to the site shall come within the limits given in BS EN 942-1:1996, for
each use, and shall be maintained until the building is completed
7.06
Plywood shall conform to BS EN 636-1:1997, -2:1997 and -3:1997 and DD ENV
1099:1998, bonding to be WBP, MR, or INT as specified on the drawing.
Plywood shall be faced both sides with birch veneer and shall be grade 2 quality.
7.07
All new and replacement timbers used for structural work are to be supplied pretreated against insect and rot attack by pressure impregnation in accordance with
BS 5268:1997 Part 5 and all cut surfaces and notches made on site shall be
treated with a suitable brush applied preservative.
7.08
Joist hangers, timber connectors, framing anchors etc shall be of stainless steel
and obtained from an approved manufacturer.
7.09
The plates, joists, rafters, purlins and other pieces used for the construction of the
roof are to be of the sizes and grades specified on the Architect's and Engineer's
drawings. All timbers shall be properly framed and secured with a suitable
number and size of nails or as specified on the drawings. As far as possible, wall
plates shall be in one piece between points of change of direction and joints
where necessary and at corners shall be halved. Wallplates shall be secured to
the inner leaf of cavity walls by 30 x 5 mm galvanised steel straps at 1.2 m max.
centres.
7.10
Provide and fix across partition walls 100 x 50 mm bearers for cold water tanks in
roof space.
Page - 15
SPF BS
7.11
Floor and ceiling joists of the sizes and grades indicated on the drawing shall be
built in to the inner leaf of external walls and lapped and spiked together at cross
walls. Joists must not be notched at bearings. Joist hangers shall not be used
except with the Architect's approval. Provide one line of herring bone strutting in
the centres of floor joists where the span exceeds 2.5 m, with 150 x 38 mm struts
well nailed and tightly wedged. Alternatively approved galvanised steel struts
may be used.
7.12
Where holes are to be cut for the passage of pipes etc they must be confined to
the middle third of the depth of the joist
7.13
The provisions of the Building Regulations shall be observed in the positioning of
any timber adjoining a fireplace, flue or hearth.
7.14
Trimmer and trimming joists shall be the same depth as the common joists and of
the thickness specified on the drawing. All mortise and tenon and half depth
housing joints shall be accurately constructed so that the alignment of the
members is maintained while the stresses of the connections are fully engaged.
7.15
Studding to partitions, casings, walls to dormers etc, shall be of the sizes
specified on Architect‟s drawings. There shall be a sole and head plate and
vertical studs at not more than 600 mm centres. Noggins shall be provided at not
more than 1200 mm centres vertically
7.16
Allow for providing and fixing noggins where required in walls and ceilings for
electrical, plumbing and other fixings.
7.17
Provide all necessary centring and templates for concrete and brickwork together
with any temporary strutting, bracing, and support for the same.
7.18
Shavings, chippings, sawdust etc., shall be cleared away and must not be left in
roof spaces, under suspended floors or in other hidden positions.
7.19
Where joinery is specified to be painted it shall be delivered to the site coated with
an appropriate primer and all built in surfaces shall be primed. Where joinery is
specified to be stained it shall be delivered to the site coated with one coat of an
appropriate clear sealer in accordance with the recommendations of the stain
manufacturer.
Page - 16
SPF BS
7.20
All joinery work shall be carried out in accordance with BS 1176, Part 2:1971.
including all necessary mortising, tenoning, grooving, matching, tonguing,
housing, rebating, and other works necessary for correct jointing and fixing in the
building whether or not specifically indicated on the drawing. All moulded work
shall be accurately worked to the full size details supplied by the Architect. Where
skirtings, architraves etc. are to match existing it is the contractor's responsibility
to take accurate profiles on site. All skirtings, architraves, plates and other joinery
works shall be accurately scribed to fit the contour of any irregular surface against
which they may be required to form a close butt connection. It is the Contractor's
responsibility to ensure that no joinery assembly is too large to be brought to its
location in the building.
7.21
At eaves provide and fix ex 100 x 50 mm triangular tilting fillet and 6 mm external
quality ply soffit as detailed on the drawing.
7.22
Supply and fix all eaves boards, barge boards eaves soffits and eaves ventilation
strips (as described under Roofing) as shown on the drawings.
7.23
Floor boards to be ex 25 mm tongued and grooved softwood boards in about 90
mm face widths with ends butt jointed. Transverse joints are to occur over joist
centres and no two adjacent boards shall have transverse joints over the same
joist. Boards must be well cramped up before nailing and the nails punched
below finished floor level. Access traps for electrical and plumbing installation to
be screwed into place.
7.24
Supply and fix standard staircase with 250 mm treads and 180 mm risers with
type of step, newels and balusters to match existing as far as practical. If not
possible, Contractor to contact Architect for advice. Handrail and string capping to
be match these of existing stair – if not possible, Contractor to contact the
Architect for further advice. Allow for assembly and fixing on site. Newels,
balusters, handrail and capping are supplied loose. Supply and fix matching
newel, handrail, ballusters etc for landing ballustrade 1100 mm high. Exposed
timber to be kept clean for clear lacquer finish. Provide 50 x 50 mm s.w. noggins
at 600 mm centres to support plasterboard soffit to stair and ex 25 x 25 mm cover
moulds to junction of plaster and string and around landing. Provide and fix ex
25 x 200 mm softwood lining to stair opening and trim to newels and string.
7.25
Door frames to all external doors to be securely fixed to pallets and built in as the
work proceeds and pointed externally with mastic.
7.26
Linings to internal door openings to be 30 mm thick crosstongued painted
softwood to extend the full thickness of the finished wall, securely fixed to pallets
built into the blockwork.
7.27
External doors to be White U-PVC.
7.28
Existing Garage Door prepared to be treated and stained in White colour to match
(in colour) New windows and doors.
Page - 17
SPF BS
7.29
Internal doors including airing cupboard to be supplied with clear lacquer finish, to
be delivered to site wrapped and the covering not removed until completion.
7.30
Window frames to be White U-PVC as indicated on the drawing, complete with
standard hinges, casement stays, fasteners and adjustable ventilators.
7.31
Airing Cupboard to be provided with two dividing shelves of separate 50 x 25 mm
wrought slats on 78 x 25 mm wrought battens plugged to side walls.
7.32
125 x 19 mm, or 175 x 19mm, or to match existing painted softwood skirtings with
rounded top edge (or to match existing) to be fixed in all rooms internally.
Skirtings to be nailed to rough grounds or to plugs fixed before plastering is
carried out.
7.33
Architraves to be fitted to all openings internally, whether frames or lined, to be
out of 78 x 25 mm, rounded on arises next to opening and with properly mitred
corners and no joints elsewhere.
7.34
Provide and fix 25 mm U-PVC window boards, nailed to plugs, with rounded
oversailing noses, extending 50 mm beyond the sides of the opening, grooved on
underside for plaster to all rooms internally.
7.35
Provide and fix over all new window openings internally, ex 50 x 25 mm curtain
track batten fixed in accordance with the directions of the lintel manufacturer.
Tracks in all cases except in Bathroom and W.C. to extend 100 mm beyond each
side of opening and are to fixed to face of wall 75 mm above soffit of window
head.
7.36
Supply assemble and fix appropriate number of kitchen units to follow Architect‟s
drawings and Client‟s recommendation. Client to suggest on desirable type and
design of units.
Allow for assembly, fixing and cutting worktops to size, forming close fitting mitred
join at corners and cutting opening for inset sink.
7.37
Provide and fix in accordance with the manufacturer's directions Duraflex
domestic type threshold strips at all external doors. Allow for raking cutting to
bottom edge of doors to fit closely over strips.
7.38
Allow for supply only door furniture to be selected by the Client/Employer. Allow
for fixing furniture as follows:
Internal Doors:
1 pair fire-closing hinges, mortice
lock or latch plus bolt on
bathroom and w.c. doors
Page - 18
SPF BS
Airing Cupboard:
1 pair [stainless] steel butt hinges
, dee handles and roller catches
7.39
Except where a painted, stained or polished finish is specified, all floors, stairs,
landings and other joinery works shall be cleaned down, scrubbed and left in good
order to the complete satisfaction of the Architect on completion.
7.40
All internal doors to be 30min FDs with self-closing hinges. Contractor to visit site
and satisfy himself as to suitability of existing doors to provide 30min Fire
Resistance and if proved insufficient, allowance for New 30FDs doors to be made.
Page - 19
SPF BS
8.00 DRAINAGE BELOW GROUND
8.01
Pipes, bends,junctions, gullies and access fittings to be 100 mm SuperSleve
flexible jointed vitrified clay to BS 65:1997 or U-PVC to BS 4660, Kitemark
certified, manufactured by the Hepworth Iron Company Ltd and installed strictly in
accordance with their recommendations.
8.02
Before starting work the Contractor must check invert levels and positions of
existing drains, sewers, inspection chambers and manholes against information
shown on drawings and report any discrepancies to the Architect. Adequately
protect existing live drains and maintain normal flows during construction.
8.03
Transport, store, bed and joint pipes fittings and components in accordance with
the manufacturer's site-work instructions. Store rubber jointing rings so that they
are not exposed to sunlight. Lay pipes straight to line and true to gradient on an
even bed for the full length of the barrel and joint using the recommended
lubricants, leaving recommended gaps at ends of spigots to allow for movement.
Adequately protect pipelines from the ingress of debris and seal all exposed ends
of pipelines during construction. Carefully backfill in accordance with the
manufacturer's instructions immediately after successful testing.
8.04
Excavate trenches to approximately 150 mm below invert level of pipes and with
vertical sides up to 300 mm above crown of pipe and width at this point as narrow
as practical but not less than the external diameter of the pipe plus 300 mm.
Ensure that the trench bottom is free of hard or soft spots and lay bed of 10 mm
single size granular aggregate to BS 882 across the full width of the trench.
After testing lay and compact further granular material uniformly in 100 mm layers
to 150 mm above the crown of the pipe. Above this level backfill with material
excavated from the trench in well compacted layers not exceeding 300 mm thick.
Mechanical compaction must not be used until there is a minimum of 600 mm of
compacted material above the crown of the pipe. Trenches under roads to be
backfilled with Granular Sub-base material type 1 Department of Transport clause
803.
8.05
Where the crown of the pipe is less than 300 mm below the underside of any
concrete slab or less than 450 mm below the surface of any road or driveway the
pipe must be provided with a concrete surround as specified below.
Where the bottom of the drainage trench is lower than and less than 1 m from
building foundations the pipe must be surrounded in 150 mm concrete and the
trench filled with concrete up to the level of the foundation bottom.
Where the trench is further than 1 m from the foundation but the depth of the
trench below the bottom of the foundation is greater than the distance from the
foundation (the critical level) the pipe must be surrounded by 150 mm concrete
and the trench filled with concrete to a level equal to the critical level.
8.06
Where a concrete surround is specified above, form vertical construction joints in
surround at face of pipe joints using 18 mm thick compressible fibreboard or
polystyrene pre-cut to finished profile of concrete and pipes. Fill any gap between
Page - 20
SPF BS
spigot and socket with resilient material to prevent entry of concrete. Lay and
compact bed of concrete grade C20 to BS 5328 (20 mm nom. max. size of
aggregate) over full width of the trench to a level just clear of pipe couplings and
allow to, set. Lay pipes on concrete bed and after testing place and compact
further concrete to encase pipe up to a level 150 mm above crown or to other
levels as specified above or shown on drawings.
8.07
Pipes passing through walls, foundations or other structural elements must be
surrounded by 50 mm of compressible material and a lintel incorporated into the
brickwork.
Page - 21
SPF BS
9.00 PLUMBING INSTALLATION
9.01
The design and pipe sizing of the heating, sanitary, hot and cold water and gas
installations shall be the responsibility of the Contractor subject to the routing of
pipework being approved by the Architect.
9.02
The entire plumbing installation shall be designed and installed in accordance
with good practice and any relevant British Standard Code of Practice and shall
comply with the Building Regulations and the Water and Gas Companies
regulations. The Contractor shall carry out any such tests as may be required to
satisfy these regulations.
9.03
Rainwater gutters, downpipes and fittings shall be the „Roundline‟ system, or
similar in black U-PVC to match existing manufactured by Osma and installed in
accordance with their instructions.
9.04
Soil, waste and ventilating pipes, traps and other fittings shall be the jointed and
fixed in accordance with the manufacturer's instructions. Pipe sizes shall be as
indicated on the drawing.
9.05
Hot and Cold Water and Gas pipework shall be in copper to BS EN 1057:1996,
BS EN 12449:1999, and BS EN 12451:1999, and shall be fixed with single copper
saddle clips except where lagging is required when two piece copper spacing
clips shall be used. Fittings shall be of the capillary type to BS 864 using lead
free solder.
9.06
Cold water storage cisterns (if applicable) shall be complete with purpose made
lid and protected vent, to BS 4213:2001. Ball valves shall comply with BS
1212:1990 Part 1.
9.07
Hot water storage cylinder(s) shall be of copper and comply with BS 699 with
integral insulation. Provision for immersion heater(s) supply and installation shall
be made.
9.08
Supply, connect and fix only 3no low level w.c. suites including directly connected
cistern, flush, seat and flap. Connect pedestal to soil pipe outlet using purpose
made uPVC gasket. Fix pedestal and cistern using non-corrosive screws strictly
in accordance with the manufacturer's instructions.
9.09
Supply, fix and connect only 3no vitreous china wash basins including (matching
pedestals – if required by client), mixer taps, waste chains and plugs.
9.10
Supply, fix and connect only 1no stainless steel sink and drainer unit to be inset
in kitchen worktop and to include mixer tap waste chain and plug.
9.11
Supply, fix and connect only 2nos vitreous china acrylic shower trays to include
slotted waste. Contractor to allow for Shower Enclosures to be supplied and fixed.
Page - 22
SPF BS
9.12
Supply, fix and connect only 2nos concealed shower mixing valves, including
flexible hose, shower head and adjustable bracket.
9.13
Provide trapped standpipe and cold water supply for washing machine and
dishwasher. Supply pipes must terminate with valves suitable for flexible hose
connection.
9.14
Wherever possible pipework shall be out of sight under floorboards, in ducts or
cupboards and in roof spaces or the like. Pipework shall be adequately fixed to
walls and other surfaces. Care shall be taken to avoid vibration being transmitted
from circulating pumps and noise caused by water hammer. Where exposed,
pipes shall be neatly and unobtrusively arranged, running vertically or horizontally
subject to any required falls.
9.15
Stop valves complying with BS 1010:1973 shall be provided on all hot and cold
water services in the following positions:
(1) On all cold water down services from a storage cistern at the cistern.
(2) On all hot and cold water service pipes before every appliance, or range of
appliances served.
9.16
Access doors shall be provided on all main soil and waste stacks with access
panels in any enclosing structure as described under Carpentry and Joinery. All
waste traps shall be accessible.
9.17
All water storage cisterns shall be insulated with purpose made plastic covered
insulation jacket held with plastic straps. All pipe-work in roof spaces or other
unheated areas shall be insulated with preformed foam pipe lagging adequately
secured, without gaps.
9.18
The overflows from all cisterns are to be of a larger diameter than the supply
pipes. They shall be carried through the external wall and terminate with a tee at
least 100 mm from the outside face of the wall.
9.19
All water storage cisterns, cylinders and the like shall be adequately supported
with joists, bearers and boarding etc and pipes shall be supported throughout
their length to prevent misalignment.
9.20
The Contractor must include for extending the existing central heating system to
serve the new extension/loft conversion, with sufficient radiators to maintain a
temperature of 20 degrees centigrade when the outside temperature is 0 degrees
centigrade. The Contractor must assess the capacity of the existing boiler to
serve the new extension and advise the Architect accordingly.
If capacity of existing boiler proves to be insufficient, New Boiler to be supplied
and connected to the specification shown on Architect‟s drawings.
Page - 23
SPF BS
9.21
Radiators shall be panel type, supplied by an approved manufacturer finished with
heat resisting primer paint, and fixed in accordance with the manufacturer's
instructions. All radiators shall have a wheel type C.P. radiator valve on the flow
connection and a lock-sheild pattern radiator valve on the return connection.
Wherever possible radiators shall be situated under windows.
9.22
The Contractor must include for extending the existing hot and cold water
services to the new fittings.
9.23
Contractor to Include a suitable sum for additional builder's work in connection
with services.
Page - 24
SPF BS
10.00
ELECTRICAL INSTALLATION
10.01
The electrical installation is to be designed, supplied and installed by the
Contractor to the requirements of this Specification and the Architect‟s drawings.
10.02
The installation must comply with the latest edition of the IEE Regulations for the
Electrical Equipment of Buildings and the requirements of the local Electricity
Company. The Contractor shall carry out any tests required to prove compliance,
give all notices and pay all charges arising.
Where installing, inspection and testing of electrical installations, either:
1. Use an Electrician / Installer registered with a Competent Person‟s scheme, or
2. Submit a Building Regulations Application, where:
a) An Electrician registered with a recognised trade body such as NICEIC,
ECA and NAPIT (who need not to be registered under a Competent
Persons scheme) tests the works and issue a design, installation and test
certificate under BS 7671
b) The work is carried out by an unregistered electrician or is a DIY
installation, the applicant is required to have the work inspected and tested
by a registered electrician as in part (a) above
10.03
Wiring generally shall be carried out using PVC sheathed cables complying with
BS 6004:2000 and shall be concealed. As far as possible cables shall be run in
the interfloor spaces or the roof void. Holes through joists shall be as near as
possible to the neutral axis and in any case not less than 50 mm from the top of
the joist. Cables shall be adequately supported and secured to avoid straining or
kinking. In roof voids cables shall be secured by buckle clips at not more than 1
m centres.
10.04
The whole of the electrical installation and all other metal fixtures and fittings to be
installed as part of the building shall be earthed in accordance with the
requirements of the IEE Regulations and the Local Electricity Supply Company.
10.05
Cables concealed in plastered walls shall be protected by galvanised metal
capping and as far as possible run vertically from floor or ceiling to the fitting. In
no case shall the plaster cover be less than 6 mm.
10.06
All cables shall be spaced at least 230 mm from any pipes intended to carry hot
water. The Contractor shall be responsible for checking the proposed runs of any
such pipes before commencing wiring.
10.07
The Contractor shall check and confirm with Client/Empoyer the location of all
fittings prior to the commencement of wiring, and should it be necessary to make
minor adjustments to the location of any fitting this shall be done without charge.
Page - 25
SPF BS
10.08
Switched socket outlets and fused connection units shall be supplied and installed
in locations as directed by the Client/Employer. All socket outlets shall be 13A
rating 3 pin shuttered, switched, rectangular pin pattern, complying with BS
1363:1995 Cooker control unit shall include 45A DP main switch and 13A switch
socket outlet with neon indicators, faceplate marked "Cooker", complying with
BS 4177:1992 and BS 1363:1995. 13A fused connection units shall comply with
BS 5733:1979. Plate light switches and ceiling switches shall comply with
BS 3676:-1:1989. Co-axial socket outlets shall comply with BS 3041:1985.
Telephone socket outlets shall be B.T. approved.
10.09
Switch plates, socket outlets, fused connection units, co-axial socket outlets,
telephone socket outlets and cooker control unit shall be flush pattern, white
plastics fittings from the Capital range manufactured by Crabtree Electrical
Industries Limited or similar approved, on concealed galvanised steel installation
boxes complying with BS 4662:1989 fixed squarely and flush with wall surfaces.
Socket outlets shall be generally positioned 450 mm above floor level or 200 mm
above worktops and light switches under 1200mm above floor level.
10.10
All pendant light points shall be fitted with an approved white plastics ceiling rose
complying with BS 67:1990, 450 mm white heat resisting flex and white plastics
shade and lamp holder complying with BS EN 61184:1995.
10.11
If new consumer unit is required, this shall be metal clad and comply with
BS 5486:1989 Miniature circuit breakers to BS EN 61008 and of adequate rating
for the duty. Miniature circuit breakers to BS EN 60898:1991 shall be provided
for all circuits. Sufficient ways shall be provided for lighting, ring main power
circuits, electric cooker, immersion heater(s), garage, door bell and two spare. A
list of circuits shall be provided clearly marked in ink.
10.12
Supply install and connect electric immersion heater(s) of the 1 kw/3kw split
element type to BS 3456.
10.13
Supply install and connect 4nos extract ventilators, Expelair or similar (to
specification shown on Architect‟s drawings) and controllers situated where
shown on Architect‟s drawings and more specifically: 1) within re-formed Kitchen,
2) within re-formed Bathroom at First Floor, 3) new WC at First Floor and 4) new
Bathroom within Loft.
10.14
From an agreed position in the roof void, run co-axial television aerial wire to the
position(s) directed by Client/Employer, 450 mm above finished floor level, for
T.V. aerial outlets.
10.15
From the position directed by Client/Employer for the BT telephone inlet, run
suitable telephone connection cable to the telephone socket connection points,
450 mm above finished floor level.
10.16
Allow suitable sum for Builder‟s work in connection with services.
Page - 26
SPF BS
11.00 ROOFING
11.01
Existing Roof Tiles removed from Rear part of Roof for Box-Dormer to be formed,
to be re-used for Front Dormer.
11.02
Battens to be 50 x 25 mm softwood grade GS to CP112 part 2, preservative
treated, fixed with galvanised steel cut or wire nails 65 mm long to each rafter.
11.03
Roofing felt underlay to BS 747:2000 Part 2 Type 1F to be fixed with galvanised
steel extra large head felt nails 19 mm long parallel to eaves so that water will
drain freely, with 150 mm horizontal laps and vertical laps not less than 100 mm
wide coinciding with supports. Cut neatly and accurately around pipes.
11.04
Mortar for bedding and pointing to consist of 1:3 cement:sand. To be finished
neatly and any residue removed.
11.05
Lead for flashings, saddles, pipe flanges etc. to be mild sheet lead to BS EN
12588:1999 unless specified otherwise. Flashings shall be in lengths of not more
than 1.5 m and fixed with lead wedges at not more than 400 mm centres.
11.06
Each course of tiles must be laid with tails aligned using special tiles at ends of
courses to maintain bond and to ensure that cut tiles are as large as possible.
Tiles must be fixed in accordance with the manufacturers recommendations using
aluminium nails, with minimum head lap to manufacturer‟s recommendation.
11.07
Form tiling edges and junctions using the specified and manufacturer's
recommended fittings and accessories to match tile colour and finish unless
specified otherwise. Fix edge tiles and fittings securely to neat true lines. Fix
every tile adjacent to an edge or junction by nailing or clipping as appropriate.
Ensure that all flashings are fixed with or immediately after tiling and are neatly
dressed down.
11.08
At eaves (to Front Dormer) fix continuous fillet to support underlay and prevent
water retaining troughs. Dress underlay into gutter and fix tiles with tails
projecting to ensure that all water discharges into gutter.
11.09
Install „Glidevale‟ monovent, or similar Eaves Ventilation system (to Front Dormer
and to main roof only if existing system proves to be insufficient) in accordance
with the manufacturer's recommendations.
Install in accordance with the manufacturer's recommendations Glydevale G3, or
similar approved tile vents to match roof tiles in colour and profile at 1 m centres
at high level on each roof slope (of Front Dormer and main roof only if it is proved
that tile vents are either non-existent or insufficient).
11.10
Remove existing tiles, battens, underlay, etc., the minimum necessary to carry out
the alterations, ensuring the minimum disturbance to adjacent tiles, re-use
number of tiles necessary to „roof‟ dormer at Front and cart away the rest.
Page - 27
SPF BS
11.11
Cover valley with strip of underlay 600 mm wide, under-lapping general underlay.
Lay valley tiles loose and coursed in with general tiling. Cut adjacent tiles to fit
neatly and fix the last tile in each unfixed course with 2 nails each.
11.12
At ridges lay a length of underlay to overlap by not less than 150 mm, securely fix
ridge ventilation terminals at a rate of 1 per 2.8 m of ridge length, to
manufacturers fixing instructions. Fix each roof tile in the last course of each slope
and make weather-tight with ridge tiles laid to a true line with edges bedded and
joints solidly bedded in mortar, neatly struck off flush as the work proceeds.
11.13
At junction of ridge with hip, valley, abutment, or higher roof slope fix code 4 lead
saddle over the underlay.
11.14
Over plywood roof deck laid to falls, specified elsewhere, lay a vapour barrier of a
single layer of BS type 3B glass fibre base felt bonded in hot bitumen, turned up
at roof perimeters. Apply built up felt roofing system consisting of the following
layers:
Top Layer: High Performance Polyester base cap sheet,
bonded in bitumen
2nd Layer: High performance Polyester base underlayer,
bonded in bitumen
11.15
The horizontal surface of the roof shall be finished with a layer of 10 mm stone
chippings in bitumen based adhesive compound. The areas not covered by
chippings shall be finished with a mineral surfaced version of the specified top
layer of roofing felt.
11.16
Any other flat-roof system proposed to be used, will be considered – subject to
discussion and approval of the Architect.
11.17
At abutments with walls or parapets the roofing felt must be turned up the wall
with an angle fillet, to finish at least 150 mm above the level of the finished roof,
bonded to the turned up vapour barrier, and covered with a lead flashing specified
elsewhere.
11.18
Where a gutter is indicated on the drawings a welted drip shall be formed in
mineral surfaced roofing felt, over a timber batten, with 50 mm downstand, to
discharge over the gutter.
11.19
The supply and installation of the roofing felt, insulation and vapour barrier is to be
carried out by an approved specialist roofing contractor who must provide a
minimum 10 year guarantee in respect of his materials and workmanship. On
completion a copy of the guarantee must be handed to the Architect.
11.20
Fascia to Flat Roof to follow a „corbelled pattern‟ as shown on Architect‟s
drawings. If further assistance / information is required, Contractor to contact the
Architect.
Page - 28
SPF BS
11.21
With regard to assembly, methodology, timber sizes etc adopted for each type of
roof construction, refer to Architect‟s drawings and Structural Engineer‟s details,
drawings and calculations.
Page - 29
SPF BS
12.00 FLOOR WALL AND CEILING FINISHES
12.01
Cement for screeds shall be ordinary Portland Cement in accordance with BS
12:1989.
12.02
Sand for screeds shall be in accordance with BS 882 : Part 2 1992..
12.03
All beds for screeds shall be well wetted, brushed clean and free from all mortar
droppings etc and well brushed with clean water before laying commences
12.04
Floors indicated on the drawings to have a screed finish shall be rendered with
cement and sand 1:3 trowelled to a uniform smooth finish free from trowel marks
and other blemishes with the following maximum permissible deviations:
From a 3 m straight edge : 6 mm.
From a 1 m straight edge : 2 mm.
Unless otherwise specified cast screeds continuously as far as possible, without
joints. As soon as screed has set closely cover with polythene sheeting and keep
in position for not less than 7 days and protect screed from physical damage. The
screed shall be reinforced with galvanized wire mesh positioned at approximately
mid-depth of the screed.
12.05
Floor and wall beds and backings shall be in cement and sand 1:3 and to be
finished to the satisfaction of the specialist executing the floor or wall finishing.
12.06
Plasters are to be Thistle board finish plaster and Carlite pre-mixed plaster
manufactured by British Gypsum Ltd. All plastering on old, previously damp,
brickwork shall be carried out using Limelite renovating plaster and finishing
plaster manufactured by Tilcon Ltd., Special Products Division.
12.07
All plasters are to be mixed and used strictly in accordance with the
manufacturer's printed instructions.
12.08
Include a p.c. sum of £25.00/sq.m. for supply only of carpet, or laminate or vinyl
floor finishes to be carried out by a specialist.
Include a suitable allowance for installation.
Add for profit.
Allow for general attendance.
12.09
Ceiling and timber partition wall linings shall be formed using 12.7 mm Gyproc
Baseboard. Gyproc Duplex Plasterboard (foil-backed) shall be used where
ceilings are under roof voids.
Gyproc Moisture Resistant Plasterboard shall be used on partitions in wet areas.
12.10
Plasterboards shall be stored and used strictly in accordance with the
manufacturers printed instructions. All joints and angles shall be filled with
Gyproc joint filler and reinforced with 85 mm wide jute scrim embedded in plaster.
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SPF BS
Plasterboards shall be finished with 'Thistle' board finish plaster 5 mm thick
trowelled to a smooth but not polished surface.
12.11
All external angles in plasterwork are to be formed using Expamet stainless steel
plaster or plasterboard beads as appropriate supplied by The Expanded Metal
Company Ltd or similar approved.
12.12
Walls and floors shall be prepared for tiling in accordance with the
recommendations of BSCP 212 : 1963 Section 3.
12.13
Walls to Kitchen (over work-tops only: up to 1,5m from Finished Floor Level, or up
to the underside of wall-mounted units), First Floor WC (up to 1,2m from Finished
Floor Level around corner of hand wash-basin only), First Floor and Loft‟s
Bathroom (full height to all walls) shall be tiled with ceramic tiles to
Client‟s/Employer‟s selection.
Round edge and round edge corner tiles shall be used on all external angles and
corners and tiling shall be continued into the reveals of all window and door
openings within the tiled areas.
12.14
Contractor to allow £25.00 / sq.m. for the supply only of tiles and allow for tiling all
walls specified on 12.13.
Include a suitable allowance for installation.
Add for profit.
Allow for general attendance.
12.15
Floors to Kitchen, First Floor Bathroom and WC and Loft‟s Bathroom shall be tiled
with ceramic tiles to Client‟s / Employer‟s selection, UNLESS client instructs for
another type of flooring (of the same supply cost / sq.m.) to be used on the above
areas.
A matching coved skirting shall be provided at the junction with all walls including
purpose made internal and external angle fittings. Matching bull nosed edge and
corner tiles shall be used at external angles and corners.
12.16
If vinyl tiles (or sheet vinyl) are selected to be used by client on any area (to be
confirmed over pre-contract meeting), supply cost to be £25.00 / sq.m.
The tiles shall be laid strictly in accordance with the manufacturer's instructions
using the recommended adhesives.
Before tiling commences the sub-surface must be dry and clean in accordance
with the tile manufacturer's recommendations.
Boarded floors must be covered by sheets of 6 mm plywood fixed with 1mm gap
between sheets with annular ring shank nails at 150 mm centres in all directions.
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SPF BS
The flooring material must be stored on site at a minimum temperature of 18
degrees centigrade for 24 hours before laying.
All seam joins must be heat welded, using the manufacturer's welding rod in a
matching colour, to afford a continuous finish (in case of vinyl sheet).
In bathroom, shower room and w.c. (if required by client instead of ceramic tiles)
form vinyl sheet into 100 mm high skirting with manufacturer's recommended
cove former and plastic capping strip and welded mitred corners.
12.17
All wall and floor tiling shall be carried out in accordance with BSCP 212 and the
recommendations of the British Ceramic Tile Council and the tile manufacturer.
Tiles shall be set out from the centre line of each wall or panel with either a full tile
or a joint at the centre.
12.18
Jointing of wall tiles is to be in white cement based waterproof grouting as
recommended by the tile manufacturer for wet areas.
All joints between sanitary fittings, Kitchen worktops and vanity units and tiling to
be sealed with white Dow Corning or similar silicone sealant, neatly pointed.
12.19
Jointing of floor tiles is to be in matching cement based waterproof grouting as
recommended by the tile manufacturer for wet areas.
12.20
All tiled surfaces are to be washed down and left clean on completion.
12.21
All finished floors must be protected from any following operations and any
damage made good at the Contractor's expense.
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SPF BS
13.00
GLAZING
13.01
The whole of the glass shall be of British manufacture to BS 952, Part 1:1995,
free from spalls, cracks, bubbles or other defects.
13.02
Clear sheet glass shall be Ordinary Quality (O.Q.). Clear float glass shall be
General Glazing (G.G.) quality.
13.03
Obscured glass shall be Pilkington.
13.04
If half hour fire resisting glass is required, Contractor to contact the Architect for
exact specification and further instructions.
13.05
All safety glass to be tested and marked in accordance with BS 6206:1994,
thickness 6 mm unless otherwise indicated. Safety glass to external high level
glazing to be toughened. All other safety glass to be toughened or laminated.
13.06
Double glazing units shall be 28 mm thick sealed units consisting of two sheets of
6 mm float glass and an 16 mm cavity sealed by aluminium edge section. Units
to be installed in Loft‟s bathroom are to have inner pane of obscure glass as per
13.03, only if required by client. Units installed in locations requiring safety glass
shall have both panes of safety glass.
13.07
All glazing shall be carried out in accordance with BS 6262:1994.
13.08
Safety glazing to be specified and installed in positions suggested on Architect‟s
drawings.
13.09
On completion all glass shall be cleaned inside and out and left perfect.
13.10
Mirrors within Bathrooms and WC to be 6 mm Electro-copper backed clear float
glass with polished edges, four times drilled for and plugged and screwed to wall
with chromium plated dome head screws and nylon washers.
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SPF BS
14.00 DECORATION
14.01
All paints, stains and other materials are to be supplied in the manufacturers'
sealed containers and are to be obtained from approved manufacturers.
14.02
All materials must be stored and used strictly in accordance with the
manufacturer's instructions and BS 6150:1991.
14.03
All ironmongery and other removable fixtures and fittings, including radiators and
electrical fittings, shall be removed prior to decoration and cleaned and re-fixed on
completion.
14.04
Floors and any fittings etc which cannot be removed must be protected during
decoration from damage and from marking by paint.
14.05
The Contractor is to allow for complete decoration and redecoration internally of
the affected from works areas ONLY.
14.06
All surfaces to be painted shall be prepared in accordance with the paint
manufacturer's recommendations.
14.07
No painting shall be carried out during wet, frosty or foggy weather or upon
surfaces not thoroughly dry. Areas must be free from dust before painting is
commenced. All newly painted surfaces must be protected from dust or other
injury.
14.08
All finished paintwork and stain shall be uniform in colour, free from blemishes,
runs, etc., and conspicuous brush marks.
14.09
Preparation of softwood joinery for painting shall include treating all knots with two
thin coats Pure Shellac Knotting, priming with 1 coat pink wood primer internally
and 1 coat aluminium wood primer externally, stopping with White Lead Putty and
rubbing down to smooth keyed surface.
14.10
Pipework and other metalwork for painting shall be thoroughly cleaned, degreased and primed with 1 coat Zinc Chromate Primer P13.
14.11
Painted joinery shall be supplied to site finished with one coat primer.
14.12
Joinery for staining shall be supplied to site finished with the manufacturer's basecoat stain. Any cut ends shall be treated with two coats of preservative and one
brush coat of penetrating stain before building-in
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SPF BS
14.13
Where and if required, carefully and completely burn off old paintwork to expose
the timber. Rub down with dry glass-paper to produce a clean, firm, smooth
surface and well dust down. Remove all nails and screw heads, or sink beneath
the surface. Gouge out large and loose knots and replace with sound timber.
Apply two thin coats Pure Shellac Knotting to all knots. Apply Wood and Metal
Primer well into grain and cover all surfaces, including thoroughly primimg all end
grains. Fill all cracks and holes with White Lead Putty.
14.14
Plaster surfaces shall be clean of all efflorescence, dirt, plaster splashes, etc., and
all cracks, imperfections and damaged plaster shall be cut out and the edges
undercut. Large cracks shall be made good with Keene's or other approved
cement and small cracks filled with Polyfilla or similar filler.
14.15
If and where applicable, existing wallpaper and lining paper to areas affected by
works ONLY is to be removed from walls and ceilings by thoroughly soaking with
warm water and using a broad scraper, taking care not to damage plaster. Wash
down new surface to remove any old size, paste, paper debris, etc., and make
good any cracks. When dry, glass paper over surface and apply coat of size.
Hang selected paper – to match existing as far as practicle (if applicable) with
good paste of stout consistency well brushed out.
14.16
All new and existing-affected joinery, pipe work, radiators and other painted
metalwork to be prepared and finished with 2 coats oil based undercoat and 1
coat oil based top coat, gloss finish, to colours selected by the Client / Employer
from the range indicated in BS 4800:2000.
14.17
All hardwood surfaces internally (if applicable) to be prepared and finished with
two coats Sikkens Cetol TS Interior lacquer, in a colour selected by the Client /
Employer from the standard range, sanding very lightly between coats.
14.18
New external joinery to be prepared and finished with two coats Sikkens Cetol
THB lacquer.
14.19
After preparation, all walls and ceilings either New or Existing affected by works,
except where tiled are to be hung with woodchip paper and finished with 2 coats
vinyl matt emulsion paint, the surface having been first primed with 1 dilute coat or
specialist primer. Contractor to base his quote on the possibility for Client /
Employer to request for wallpaper on certain areas.
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SPF BS
15.00 EXTERNAL WORKS
15.01
Carefully take up existing paving slabs before construction is commenced and
store for re-use.
15.02
If required, supply and lay pressed precast concrete paving slabs to match
existing. Slabs are to be laid with staggered bond with joints of 2-5 mm and
stabilised with several passes of a plate vibrator. Sweep fine dry sand over the
paved surface and vibrate until all joints are filled with sand and sweep away
surplus.
15.03
Contractor to make sure that all tree(s) and planting beds are protected
throughout duration of works. If works relating to New Planting is required as part
of the works, Contractor to inform and liaise with Architect in this respect.
15.04
As works in relation to proposed development will involve alterations to Side
Lobby, Contractor to make sure that there is a suitable sum allowed for
modifications / adjustments to Side Lobby‟s roof and Finished Floor and these
operations will form part of the Contract Works.
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