A Guide to the Building Regulations for Replacing Windows and Doors

Summary: This is a summary of the regulations that affect you when you want to replace doors or windows. There is advice about replacing windows and doors with regard to the building regulations. This project will help you to replace windows and doors legally.

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Replacing windows and doors is not quite such a simple procedure as it was pre April 2002. Since then you must have approval from the Building Control department of your local council to say that the replacement has been done in accordance with the building regulations. These regulations apply in England and Wales.

This means one of two things. The installation has to be done by an individual or company who is registered under the FENSA registration scheme. A glazing company with FENSA registration will install the windows and doors and issue you with a certificate to prove that the work has been done in accordance with the regulations. You must also make sure, as you are potentially changing the external appearance of your home, that you do not need planning permission for your changes.

FENSA stands for Fenestration Self Assessment Scheme and was set up by the Glass and Glazing Federation along with other organisations within the glazing industry to ensure that all glazing in the UK complied with current Building Regulations.

The other way of replacing your windows is to do it yourself -BUT - You must still contact your local council and tell them what you intend to do. You must supply dates for when you plan to do it and arrange for them to visit your home during and after the installation to make sure the work is done in accordance with the various regulations that are involved. These regulations include:

  • L1 Conservation of fuel and power. The window you use must attain the required U value. This can be achieved in a few ways but you may be asked to prove a) that the glass you use is of a recognised quality or make and b) the calculations to show how your U value is attained.
  • N1 Glazing protection against Impact. There are many rules governing the height of windows and the type of glass used in them.

Other regulations may also come into force when changing windows and doors. These may include Structural regulations found in Approved Document A which deals with whether the support above a window is suitable for that window. Approved document B which deals with how occupants may escape in the event of a fire. Approved Document F, assessing whether the new installations provide enough ventilation, Approved Document K dealing with how high the window cills are and how much protection there is to stop people falling out of the window. Approved Document M dealing with new entrances and the ability for it to be used safely by a disabled person.

All of the above regulations can be seen by clicking on the blue links but the message here is clear. It is against the law to fit windows and doors which do not comply with the building regulations and are fitted in a way which can not be approved by them.

If you try and sell your property without the correct certificates for any installations done after 01 April 2002 you may well find yourself in serious trouble.


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