Guidance for building regulations applying to windows, doors, roof lights and roof windows
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;
Use as a Fire Escape
Air Supply and Ventilation
Means of escape in case of a 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.