Page last updated at 10:05 GMT, Tuesday, October 6 2009

Guidance on Replacement Glazing and Doors

Replacement Windows, Roof lights, Roof windows and doors

To ensure that the completed installation of replacement windows etc. complies with the relevant requirements of The Building Regulations, regard should be given to the following

Means of Escape in Case of Fire
Means of escape windows e.g. windows to habitable rooms in the upper storey of a building should have a clear unobstructed opening of 0.33m2 with a minimum dimension of 450mm.

Ventilation
The openable area of a window with a hinge or pivot that opens 30 degrees or more should be equivalent to a minimum of 1/20th of the floor area of the room.  For a hinged or pivot window that opens between 15 degrees and 30 degrees the opening part should be at least 1/10th of the floor area of the room.

Where the original windows were fitted with controllable trickle ventilators the replacement windows should also include them with minimum unobstructed areas of 5000 mm2 for habitable rooms and 2500 mm2 for kitchens, utility rooms and bathrooms.

Where existing windows are not fitted with trickle ventilators it is strongly recommended that replacement windows include them to help with control of condensation and improve indoor air quality.

Combustion Air
If an existing window or door has a permanent vent to provide combustion air to heat producing appliances, the new installation should provide at least the same amount of permanent ventilation.

Thermal Insulation
New glazing should have an average “U” value (heat loss rating) not exceeding 2.0w/m2k or a centre pane “U” value not exceeding 1.2w/m2k.

A centre pane value of 1.2w/m2 may be achieved with double glazing having a minimum gap of 16mm together with low E glass to the inner pane (E relates to the heat emission rate of the glass).

Safety Glazing
Glazing in critical locations should be safety glass in accordance with BS.6206.  Critical locations are defined as areas in and adjacent to doors up to 1.5m above floor level and 300m each side, and windows and locations within 800mm of the floor level.

The above is intended as general guidance only therefore should you require additional assistance or information please contact the Councils Building Control Unit on 023 8068 8327/8294 or email building.control@eastleigh.gov.uk

Please Note:  You are required to notify the authority on completion of works to enable an inspection to be carried out.