| Following a change in the Building Regulations, from 01 April 2002, a Building Regulation application will be required for replacement windows, doors and roof-lights. The requirement does not apply to repair work on parts of these elements. Where the installation of a new window, door or roof-light relates to a bay window, or involves enlarging an existing opening, a Building Regulation application must be submitted to include the structural work as well as the replacement element.
I thought replacing windows did not need Building Regulation consent?
For many years, it has not been necessary to apply for Building Regulation consent when replacing windows in existing dwellings unless a structural alteration was involved. This usually only occurred when the existing opening was being made wider, which made the installation of a new support lintel necessary. From the 1st April 2002 however, all owners replacing windows need to make an application, and the new windows themselves will have to fully meet the requirements of the Building Regulations. So even if you are replacing only one window with one brought from a local DIY centre you still need to follow the guidance below.
It is most important that you obtain the necessary consent, as solicitors will specifically check this when you sell your property. If you cannot produce the appropriate documents it is unlikely that the sale will be able to proceed.
What do I have to do?
You have a choice, you can either -
a) Use an installer registered under the FENSA scheme run by the Glass and Glazing federation, in which case you do not need to make a Building Regulations application to the Local Authority. Your installer should then ensure your windows comply fully with the Regulations and will supply you with a certificate confirming this when the installation is complete. If you wish to use this option please ensure that your installer is properly registered under the scheme before placing an order. You can check this and find more details of the scheme by visiting the Glass and Glazing federation website at www.fensa.co.uk ; or
b) Make a Building Regulations application, and in most cases the simplest way of doing this will be to submit a Building Notice. If you require a copy of the form, please ring your Local Authority. You must then complete the form, and return it to us together with the appropriate charge at least two working days before removing the old window(s).
Once we receive the Building Notice, a Building Control Officer will normally visit your property twice - once during and once after the replacement windows are installed. When the works have been satisfactorily completed we will issue a Completion Certificate to confirm this, and we would normally advise you not to make the final payment for the work to your installer until the Completion Certificate has been issued.
How much will it cost?
If you use a contractor registered under the FENSA scheme the cost should be built into the quotation for the works you are given. Where you decide to make a Building Notice application to the Local Authority, we will make a charge for dealing with your application. Building Regulation charges for applications for replacement windows, doors and roof-lights are assessed on an estimated cost basis.
For costs please contact your local Building control section.
What regulations do the windows have to comply with?
Where the windows are to be installed in a listed building, or in a building in a conservation area, it may not be necessary to comply fully with all the requirements below - please contact us for advice and remember that you may also require Planning or Listed Building Consent for your proposed work.
1) Thermal insulation (Part L1B 2006 Work in existing dwellings)
The replacement windows will need to meet the new thermal insulation requirements of the regulations. If the replacement windows have wooden or plastic frames, then the glazing needs to achieve a maximum U-value of 2.0W/m²K while for glazed doors a slightly higher U-value of 2.20W/m²K is allowable. Please note that these values are very difficult to achieve and many double glazing units currently on sale will not meet these new standards. Take great care when ordering new windows that your supplier can prove the glazing units used will satisfy this requirement, as the Building Control Officer will need to see this proof before issuing a Completion Certificate. We would particularly recommend that you leave any labels on the glazing in place until after a satisfactory inspection has been carried out by the Building Control Officer.
In some cases it may be permissible to use glazing units which do not meet the above specifications, but to do so you (or your supplier) would have to submit calculations to prove that the overall insulation requirements of the regulations would still be met. This may be possible if other insulation measures are undertaken at the same time as the window replacement - for example, installing cavity wall insulation or "topping up" loft insulation. The benefits gained by installing this extra insulation can be used to offset the higher losses through the glazing, but this should not be undertaken lightly. We would strongly advise you get any such calculations checked by the Building Control Officer well before the replacement windows are installed, so that expensive mistakes can be avoided
2) Means of escape (Part B1- Means of Escape)
All first floor windows in dwellings should ideally have opening lights large enough to allow you to escape through them if you were trapped in the room by a fire. This also applies to rooms in bungalows which open into a hall (unless the hall itself has an external door through which you could escape). To meet this requirement all such windows should have an unobstructed openable area of at least 0.33m² and be not less than 450mm high and 450mm wide (the route through the window may be at an angle rather than straight through). The bottom of the openable area should be less than 1100mm above the floor.
The following diagram represents this pictorially.
If your existing windows do not have opening lights which meet the above requirements, we would strongly recommend for your own safety, that you take the opportunity to provide them in the replacement windows. This is not a however a requirement of the regulations, which simply state that the replacement windows must be no worse than those they replace in this respect. Where the existing windows already have opening lights which are larger than the above requirements, those in the new windows can be reduced in size provided they are not reduced to less than the dimensions above.
3) Safety Glazing and Safe Opening (Part N -Glazing)
Low level glazing (within 800mm of floor level) and glazing in doors should generally be of a type that will break safely. In practice this means such glazing should be either laminated or toughened. Manual controls for opening should be within easy reach. The Approved Document to part N of the Building Regulations gives maximum sizes according to the thickness of glass - for example, in a single pane less than 1.1m square - 8mm glass would be satisfactory, and locations for manual controls.
4) Structural safety (Part A – Structure)
If the replacement windows are wider than those they replace, or involve the replacement of bay windows, then the Building Control Officer will need to be satisfied that proper structural support is provided above the window. In older buildings, the timber frame of the window was often sufficiently strong to carry the load of a wall or roof above it without a lintel. Obviously in these cases either a lintel needs to be installed when the window is replaced, or the new frame carefully reinforced to carry the load.
5) Ventilation (Part F 2006)
The Building Regulations require that adequate ventilation is provided for people in the building and this should be considered when deciding on the size of opening lights in the replacement windows. For most rooms, one or more opening windows totalling 5% of the floor area. For kitchens, utility rooms and bathrooms an extract fan is also normally required.
Although not required by regulations, background "trickle" vents totalling 5,000mm² for habitable rooms and 2,500mm² for wet rooms will enable your building to breathe without breaching security.
In some cases the existing windows may contain a permanent vent to supply combustion air to a heating appliance, although this is now rare. If this is the case however you should ensure that either the replacement window contains a similar permanent vent, or that some other means of providing the required ventilation is installed at the same time
|
