.MTC REVISION DOCUMENT. Revision 3
The following information is designed solely as a revision document aimed at
supporting the installers who are to undertake their MTC knowledge theory tests. The
knowledge derives from the GGF Best Practice Guide for Installers and from BS8213.
The reason for this document is that all too frequently we can become engrossed in
booklets 70 to 90 pages in length when in reality we only need to look at the basics.
However the information in this summary document should, but may not, cover every
single question in the MTC tests and site observations. We would still advise you look at the
other support material available including the GGF Best Practice Guide and up to date
Building Regulations information.
MTCs cover a wide range of knowledge requirements that are mainly concerned with
the best recognised practice for installation and the need to understand the building
regulations related to our industry and, last but not least, Health and Safety. Please note
that all legislation, regulations and best practice apply to every company regardless of
the size from the typical “one man band” scenario to the largest organisations
Health and safety at work act revised in 1974 is the recognised industry legislation that
sets out to ensure everyone involved at work is protected from harm. The HSE sets out
legislation documents that pinpoint potential areas for concern and these areas are
highlighted within the sub sections below. Where organisations employ 5 or more
people the Company must have a formal written Health and Safety policy.
PPE., personal protective equipment, this regulation states that the employer must have
carried out a risk assessment and ensured the work force are equipped with the PPE to
carry out their work as safely as possible. It is worth noting that PPE should be the last
resort if the hazard can be avoided or removed then it should be. It is the employer’s
responsibility to provide the employee with the required PPE, the employee has a duty
of care to co-operate with the employer and to take reasonable care of their equipment.
Standard prescription glasses are not acceptable form of eye protection, special
prescription safety glasses can be obtained or the use of over -glasses is required
When cutting using grinding equipment it is recommended that all employees should
wear a full face visor, safety footwear and either a dust mask or respiratory equipment.
RIDDOR, reporting of diseases or dangerous occurrences this regulation sets out to
ensure that all employees and employers recognise the need to record accidents. It is
recommended that all accidents, incidents or near misses should be reported to the
company or employer. Only accidents that result in 7 days and over from work need
reporting to the HSE, the reason for this is that the companies could be investigated if
there becomes a trend and evidence is kept for a number of years. Installation vehicles
should carry in date first aid kits, a fire extinguisher and an accident reporting book.
Other matters covered under RIDDOR include the collapse or partial collapse of
scaffolding.
COSHH, control of substances hazardous harmful to health. This regulation ensures that
there are safe guide lines for the transportation, storage and use of substances or
chemicals. To ensure the end users are kept safe symbols are located on every product
these symbols indicate the controls and potential harm for the user and those affected
by their use. The user should recognise these symbols and should follow all safety
guidance for use, transportation , storage and disposal of all substances.
Work at heights regulations. This regulation is aimed at protecting those who work at
height and their safety, where working at heights is involved there must be a risk
assessment carried out before work commences. So what is classed as working at
heights? Basically working anywhere from which a person could fall is classed as
working at heights. If the use of access equipment is required only trained and
competent persons can legally erect the equipment. Any access equipment delivered for
the purpose of use must have a test report to state it has been checked and is fit for
purpose.
Every time a mobile scaffold is moved it must be checked and signed off accordingly by
a competent person, mobile towers must not exceed 4 metres whilst being moved.
Hand rails or guard rails must never exceed 470mm centres. If scaffolding has been
erected for the installers by contractors there must be a visible hand over tag that
indicates the scaffold is complete and is safe to work from.
When using a ladder for access care should be taken to ensure the ground is good, the
correct angle of lean is correct (1 in 4) or 75%, stand offs and stabilizers are in place
and that you can maintain 3 points of contact whilst limiting the amount of work carried
out from the ladder.
Manual handling. This regulation gives guidance to the movement and transportation of
materials either by hand or when using equipment to make the lift. In short risk
assessments should be carried out prior to making the lift, the route must be planned,
and obstacles removed, areas for rest planned and safe areas for storage are designated.
Weights shape and size of the products must be considered and additional labour may
be required. HSE now recognise that they cannot specify a set weight for lifting by either
male or female but recommend the weight should be something the individual feels
comfortable with and risk should be taken into account. When using equipment to make
the lift the user needs to ensure the equipment is fit for purpose and that you are aware
of the weight to be lifted and the capacity or safe working load of the lifting equipment.
PUWER, Provision and Use of Work Equipment regulations. This regulation controls
the use of equipment mainly electrical and gives safety guidance for the user. All
equipment should be fit for purpose, all electrical equipment from new will have been
tested and the pass label will clearly be displayed on the product. When using power
tools it is recommended that 110 transformer be used and when using 240 direct there
must be a RCD breaker to protect the source. Portable appliance testing (PAT) at regular
intervals is recommended but is not law just best practice. Where possible always use
cordless power tools.
Control of Asbestos regulations, this regulation gives guidance on asbestos and
recommends what should be done if asbestos is present or suspected. Best practice is to
recognise where asbestos could be found such as infill panels, soffits and suggests that if
you are unsure work must never continue. The asbestos or suspected asbestos should
be analysed before work continues and customer or client liaison is strongly advised.
It is recommended that fire extinguishers are carried on all installation vehicles. Fires
do occur from time to time and we should be equipped to deal with them. All companies
should comply including the small companies where their vehicles are effectively their
mobile offices also.
See chart for Fire extinguisher use below.
Conclusion
There are numerous additional regulations that are aimed at keeping us safe at work
and are the main issues currently relevant to the MTCs only. Health and safety must be
taken seriously everyday someone is severely harmed or lose their life because of an
accident that could have simply been avoided. You must always remember that “you are
responsible for yourself and anyone who is affected by your acts or omissions at work”.
The acts are the things you have done, and the omissions are the things you should or
could have done to prevent accidents
INSTALLATION BEST PRACTICE.
The following is the recognition of best practice of installation mainly involved within
the removal of existing frames and installation of new windows and doors. As with
everything the following information is aimed at the perfect scenario because the
perfect scenario is the only way to set best practice standards and guidance.
What is a site? All places of work are classed as sites and are normally either a
commercial site or a domestic site either way work on any site must be carried out
safely and in accordance to current health and safety legislation and building
regulations.
The installer should carry out their own risk assessment when arriving on the site of
work. Reasons for carrying out a risk assessment are to ensure the hazards have not
altered from the date of survey and the installer is sure it is safe to work. If scaffolding
has been erected for use then visible tags or hand over certificates must be observed
and in the event that access equipment is required only competent trained persons can
erect the equipment. If hazards are identified that are not on the risk assessment then
adequate precautions must be taken and in serious implications such as the suspicion of
asbestos then work must stop until the materials have been analysed. Temporary
supports should be used to support the structure if the aperture is being widened, there
is no sign of the existing lintel, and if you think the brick work has possibly moved.
Preparation to start work
The usual checks must be to ensure that the replacement products are correct and
measurements of the new products are taken and matched against the survey and
actual structural opening. We also recommend that the replacement products are
building regulation compliant or at the very least not making the ingoing frame worse
than the outgoing frame. Structural checks should be carried out looking for signs of
fresh movement or subsidence.
The installer should take every precaution to ensure that within reason they manage
and monitor the site for any potential health and safety issues. It is worth noting that
the installer is always responsible for anyone or anything that could be affected by their
work. Remove-move all vulnerable objects and place protective sheeting inside and
outside accordingly. Ensure safety signs are erected and all areas cordoned off to
prevent unauthorised access to the working environment.
Frame removal
All frame removals are different within their nature and every installer will approach
the work in a different manner. Either way the work must be done methodically and
safely. Speed is not of the essence careful work in the preparation will save time in
making good in the long term. Every aperture is different and care must be taken in
removing the old materials, all DPM’s are there for a purpose and should not be
removed if they are unavoidably removed then legislation says they must be replaced,
the replacement window will not protect against damp in the apertures where the DPM
has been removed.
If there is no sign of a lintel above the frame then invasive surgery is required to
confirm if a lintel or structural support is present. If there are no lintels then the
aperture must be supported correctly and a lintel or other structural support installed,
under no circumstances must the replacement window be expected to withstand direct
loads. When replacing bay windows temporary structural supports must be used to
support the bay during removal and replacement. Bay windows must have load bearing
jacks that run through the cill directly to the head. If you cannot confirm the bay is load
bearing then you must assume that it is load bearing and therefore install bay pole
jacks. A signed customer waiver is not acceptable where a lintel should be used.
Frame preparation
Frame preparation will be different from one system to another, if frame extensions or
build ups are required we recommend that silicone is used between the dry joints and
the extensions are screwed to the frame at 300 to 400 centres. The joint between the cill
and frame should have a silicone tray installed and fixed to the frame at centres 300mm
to 400mm. The cills should be cut to allow for additional expansion 2mm for white
products and 5mm for foiled products. Some frame preparation will be system specific
but these areas are not accounted for within the MTCs.
Aperture preparation
Aperture preparation will vary dependant on the type of property and the type of frame
that will have been removed. In general remove old nails, loose mortar, and old mastic
lines, maybe remove the nosing from the window board. It is important to note that oil
based mastics must be entirely removed during aperture preparation failure to do so
could result in poor adhesion with other products, discolouration of the new products,
and DPC failure. Aperture preparation also takes into consideration fixing and fixing
points. The installers should recognise where they intend to fix and should prepare the
aperture accordingly. DPM must be installed in the required areas that will be
dependent on the property type and if timber is used to fix against then the timbers
should be treated and used in conjunction with DPM’s.
Frame positions and aperture preparation
Frame installation.
Following the aperture and frame preparation the frame can be lifted into position. It is
important to consider the location of the frame within the aperture to ensure a secure
fixing and thought given to internal and external finishing’s. When projecting or over
hanging cills are used it is recommended that the cill must extend a minimum of 25mm
from the face of the structure. Ideally frames should have 5mm all round clearance,
giving an overall tolerance of 10mm from the tight aperture size for white frames up to
2400mm in width, for none white frames 15mm tight tolerance is required up to 2400
in width.
Fixings
There are two principal methods of fixing available, which may be used separately or in
combination, these are through frame fixings and lug fixings.
If lug fixings are used they should be of a suitable material to resist corrosion and, if
used externally they should be secured to the surround using “one way screws” or other
security screws.
Screws should be sized to penetrate at least 25mm into timber, brick, block or masonry.
Connections to steelwork over 2mm thick should be into pre-tapped holes with machine
screws of a minimum 5mm diameter or alternatively power driven hardened selfdrilling screws. Packers/shims must be used appropriately between the frame and
aperture behind the fixings and under all mullions. Frame packers will hold the frame
solid and square and should span the frame from back to front and extruded from
suitable material to avoid corrosion.
Any electrical or specialist items, such as television aerials or telephone wires should
be re-routed around the frame of the window. Where this is not feasible, then
alternatives should be agreed with the customer and any specialist.
.
It is recommended that all 4 sides of the frame should be fixed where possible and a
minimum of 2 fixings per jamb is required. The presence of pre-cast concrete or steel
lintels may make it impracticable or pose severe problems in achieving the fixing
distances and locations.
In these instances the use of polyurethane foam could be used in conjunction with
mechanical fixings with a fixing tolerance recommended between 10 and 15mm only.
Please note polyurethane foam must never be used as the sole method of fixing, but
could additionally be used for perimeter filling for added insulation to prevent cold
spots.
See below for fixing distances.
PVC-U windows and doors
Where possible, all four sides of the frame should be secured as follows:• Corner fixings should be between 150 mm and 250 mm from the external corner.
• No fixings should be less than 150 mm from the centre line of a mullion or transom.
• Intermediate fixings should be at centres no greater than 600mm.
• There should be a minimum of two fixings on each jamb.
If the head is fixed with polyurethane foam, then the fixings at the head may be as
follows:
• Frame width up to 1200mm – no fixings
• Frame width 1201mm to 2400mm – one fixing
• Frame width 2401mm to 3600mm – 2 equally spaced fixings.
Timber windows and doors
Where possible, the sides of the frame should be secured as follows:a. Corner jamb fixings should be between 150 mm and 250 mm from the external
corner.
b. Intermediate fixings should be at centres no greater than 600mm.
c. There should be a minimum of two fixings on each jamb.
d. On windows over 1800 mm wide, central head and sub-sill fixings should be
provided.
Frame preparation for glazing.
Care should be taken to ensure that all swarf and other debris are removed from the
rebates and that checks are physically carried out to ensure drainage is effectively
working. Bridging packers or system specific glazing platforms should then be placed
appropriately to suit the frame before commencing with the glazing.
Glazing.
Glazing should be carried out to ensure the frame is fully operational after the process
and there is no snagging between the sash and outer frame during operation and that all
drainage is not affected. The sash should be level against the outer frame and constant
checks made for ease of operation during the glazing process. All decorative glass must
be fully aligned. All glass must be compatible to building regulations requirements and
should be either toughened or laminated. The logo that indicates the glass is safety
glazing must be visible after installation with all markings clearly displayed. Please note
that if the safety glass logo is not clearly visible after the installation then the unit will
have to be re-placed or re-etched. If the installer finds that the glass is within the critical
glazing area but is not safety glass a re-placement unit must be ordered and the original
must not be installed as a temporary measure. A flat panel or boarding must be used,
remember the installer is responsible for what they install and finish.
Timber glazing requires the specialist guidance; all other questions related to
installations remain the same and apply accordingly. Most timber systems when glazed
will require a sealant to cap the external bead to protect against the weather unless
specified different.
Finishings
Finishings will vary with the type of installation and surrounds both internally and
externally. Most surveyors will specify the finishing details but unforeseen and hidden
problems could have a bearing on how the work is completed.
Perimeter joints should be sealed on both the outside and the inside, with a sealant
appropriate to:
• the frame surface
• the substrate material
• joint size and configuration
• anticipated joint movement
• anticipated exposure to weather.
Gaps between the frame and aperture must be sealed using a low modulus silicone,
please note that any gaps larger than 6mm all-round the frame must have a gap filler
applied or a PE rod before sealing. Care should also be taken to ensure the sealants are
the correct colour and that they are in date and match the specification.
The gap filler must not allow the silicone to adhere to it therefore ensuring that the
silicone is pressed firmly to the sides of the frame and aperture and will allow for
movement. PVCu /Cellular trims used for external purposes must only be used for
enhanced visual appearance and not used for weatherproofing. The frames must be
weatherproof before installing any final cover trims. Likewise when making good
render around the edge of frame weatherproof the gap between the frame and aperture
prior to replacing the render and any final touches.
Hand over
Before hand over ensure the site is left completely free from any debris and all
vulnerable objects have been replaced and that all dust sheets have been removed.
Before leaving site ensure the client is aware of how to fully operate the newly installed
products. The best way to do this is to demonstrate the operation with the client and
then invite them to operate the systems under your supervision. It is also good practice
that if the work will continue for more than one day advising the client on how to
operate the new fixtures could be advantageous in any event of any emergencies. The
sales of goods act 1994 says warranties must be issued and that customer details,
maintenance contact numbers and validity dates are clearly visible on all warranties.
Maintenance.
Advising the client on basic maintenance is always good practice and will help to
prolong the effective life of the products. Cleaning of the frames is best using a detergent
and warm water or a non-abrasive cleaner, the cleaning of glass is recommended using
detergent and warm water or a recognised glass cleaner, all abrasive products must be
avoided at all times.
Light oil is recommended to periodically lubricate moving parts and areas of friction
such as the friction stays, locking mechanisms and keeps.
Building regulations.
Building regulations are a key factor in recognising what is legally required within the
replacement windows and door market and regardless to your individual job role all
installers and surveyors must know and understand building regulations relevant to the
replacement sector.
UNDERSTANDING OF THE BUILDING REGULATIONS.
Overview.
The regulations basically state that all re-placement windows and doors should not be
any worse than the original/ existing in design only.
The only regulations that must be complied with are those for (DOC –L) all glass must
be low emissivity (low-e) , and safety glass must be installed to all critical glazed areas.
(DOC-K).
All the other building regulations should be complied with where possible.It is
recommended that if the original/existing is not fully compliant but could be just by
simply changing the design of the proposed replacement products then they should
always be altered because this is seen as best practice.
Document A, this refers to “Structure”.
Replacement bay windows must be adequately supported during their removal and the
new bay windows re-installed with bay post jacks and supports with top and bottom
spreader plates for structural integrity.
The replacement products should have structural jointing strips in-between the frames
such as mullions in a door combination frame this will provide additional strength to
the product.
Where windows are to be re-placed checks should be made for the presence of a lintel.
The surveyor should identify if existing lintels are in place and if not it is recommended
that lintels are always installed. PVCu frames must never be load bearing.
Where a window and brick work is to be removed to form a new door access then these
are now only covered under building control, Fensa /BBA do not recognise the process.
This applies to any structural alterations.
Loadings associated with “structure” are, direct loads, wind loads, imposed loads.
Document B - this relates to fire safety
Basically, every window in a habitable room should have two means of escape. 1 means
of escape would be from a room that leads to a protected stair way the other being from
an egress window. Normal domestic dwellings will not have a protected stairway these
are normally found in new build flats or regulated and approved conversions, therefore
best practice suggests the window within the habitable room should have a fire escape
incorporated within the design.
Fire escapes should have non key locking handles, must have egress hinges and where
possible be not less than 450mm x734 in either width or height ( 0.33m2). When
possible the bottom of the operable area should be no more than 1100mm from the
floor. Remember you cannot make it any worse than the original /existing.
Please note a fire escape opening 450mm x 450mm does not meet compliance.
Document C- resistance to moisture
This document relates to the prevention of moisture to the dwelling.
Try to avoid unnecessarily removing DPC during the removal of the old frame work; if it
is removed it must be replaced without hesitation. It also includes installing a DPC in
and around the aperture to prevent the transference of moisture or damp when and
where applicable. Other areas that will prevent damage from moisture are effective
drainage, sub cills with the correct projection and effective sealing of the frames.
Document F –Ventilation.
There are two different types of ventilation recognised and required within a dwelling
one is purge ventilation and the other is background ventilation.
Purge ventilation is required where there could be a need to have rapid air change in
challenging conditions.
Requirements for purge ventilation via windows
For hinged or pivot windows that open 30 degrees or more, or for sliding sash windows,
the area of the opening should be at least 1/20th of the floor area of the room.
For a hinged or pivot window that opens less than 30 degrees, the area of the opening
should be at least 1/10th of the floor area of the room.
Requirements for background ventilation
Where the outgoing window provided background ventilation, the replacement window
should also provide background ventilation. It is acceptable for alternative high level
ventilation to be provided, e.g. high level air brick. Typically, background ventilation is
positioned at least 1.7 metres above finished floor level to avoid discomfort due to
draughts.
Where trickle ventilators are used to provide background ventilation then the following
performance is required:- habitable rooms 5000 mm2 equivalent area. Kitchens,
bathrooms and other wet room areas require 2500 mm2 equivalent area.
Document J Combustion appliances and fuel storage.
The replacement window should not make the ventilation requirements any worse for
any combustion appliances than the original. In the event of a permanently open
combustion vent being present within the property the installer must ensure that the
replacement product is compatible with the existing.
If there are any doubts please seek advice from a qualified gas safe engineer who should
also be a member of a competent person scheme.
Document-K protection against impact.
This document does not apply to the existing/original scenario therefore is a must do.
All replacement products must comply with this document for safety glazing. All glass
that is installed in, all doors, all side panels within 300mm of a door, all glass areas
800mm of the finished floor must have safety glass.
Any other potentially vulnerable areas must be considered for safety glazing.
All safety glass must be clearly and visibly marked, the safety glass can be either
Toughened, Laminated or wired safety, if wired safety glass is used it must never
exceed 900mm in width or height.
All first floor windows and areas above below 800mm must have restricted stays to a
maximum 100mm to prevent falls and 100mm restrictions where there is a danger of
collision from walking past an open window. Please note document K is legislation for
safety glazing for England, document N remains legislation in Wales only.
Document L Conservation of fuel and power.
This document does not apply to the existing/original scenario therefore is a must do.
All replacement glass must be low emissivity glass regardless,
The frames should be rated A to G according to BFRC.
Additional insulation should be used around the frames, bays and bay conversions to
prevent heat loss-cold air transference and cold spots.
BFRC are the organisation that rates frames and glass combined.
BFRC, rate the energy efficiency of all windows, the highest being A rated the lowest being G rated.
To make it easier building regulations only recognise C rated and above.( see chart below)
Document-M
This refers to access to and from a dwelling; the main entrance door should be made for
ease of access. It should not be worse than the existing and when possible be made
better.
Doors after 2004 will have a minimum opening width of 775mm which is the
measurement recorded between the edge of the outer frame to the face of the open door
leaf/slab all doors could have restricted thresholds for ease of access.
Some areas where the weather exposure is low should not exceed a threshold height of
35mm and areas of high exposure should never exceed 50mm
DPM must be used between the cill and brickwork and any other areas of the aperture if
it is required.
All windows and doors should now be CE marked in accordance with European
standards for recognition.
FIRE RATED GLASS INFORMATION. (Brief information)
Fire rated glass is used to protect areas, stored materials and people from harm or damage.
How is it rated?
Fire glass is rated in two ways.
1 = Integrity
Glass rated as integrity only is a fire rated glass that will prevent the passage of flames from
one area to another. The product itself can be rated from 30 minutes to 120 minutes. Fire
rated glass that is integrity only is designed to prevent the spread of flames but will not
prevent heat transferal from one side of the building to the other.
2 =Integrity and Insulation.
Glass rated integrity and insulation will provide fire protection from the spread of flames
with the added properties that allow this glass to retain the heat from the fire side of the
building and prevent the transfer of heat from one area to another. Again this product can
be rated from 30 minutes to 120 minutes.
Eg If there was a room where all the substances stored were potentially explosive the glass
installed would have to be integrity and insulated because the transferal of heat could
trigger an explosive reaction.
Note, all glass types are designed to match criteria that suits today’s market, all glass is
tested under extreme conditions along with the supporting materials such as the frame,
sealants, fixings and beading. Therefore any glass supplied must be installed using the same
products that gained the pass mark. Other materials will not be compatible and will cause
the glass/ screen to fail.
The spread of smoke and fumes is also an issue and new systems take this into account for
example fire rated doors that are increasingly installed.