Frequently asked questions about window replacement

Do I have to use PVCu windows?

No, you can install wood, metal or PVCu windows providing they are draught-proofed and give thermal insulation, o the standards laid down in the Building Regulations.

Do I have to double glaze?

Yes, unless the building is an historic building and you must replace the windows to match the existing to comply with Planning Legislation, in which case there is some flexibility. The conservation officer will give guidance as to which buildings fall into this category.

Do I have to use special double-glazing?

Yes.  There are various combinations of glazing thickness/cavity thickness and cavity filling (eg Argon, or Air) which give differing thermal standards. Generally you should use low E glass with double glazed units with a 16mm air gap or a 12mm Argon filled cavity.

I don't want to use low E glass, what can I do?

You may be able to use triple glazing, i.e. three panes of glass

What about conservatories?

The glazing in conservatories does not need to be low E glass if the conservatory is separated with a wall and a door from the rest of the house. The heating in the conservatory must have separate heating controls from the rest of the house.

When do I have to use safety glass?

Safety glass, toughened or laminated must be used in all doors. Also all glazing within 800mm of the floor must be safety glass to cope with the weight of someone falling against it, further measures may be necessary to deal with the risk of anyone falling from low level window openings

How can I tell if it is safety glass?

The manufacturer will have put a British Standard 6206 kite mark on the glass.

Do I have to have opening windows?

The room will need ventilation, so an opening window is needed. The opening window needs to be at least the size of the existing opening or not less than 1/20th of the floor area of the room. You also need to put in ventilation for any gas fires or boilers in the room. Check to see if the room already has air bricks installed, otherwise you will need to put in some fixed vents in the windows. It is also necessary to have "trickle ventilators" to avoid condensation

What other things do I need to consider?

You need to talk to the Building Control Surveyor about fire safety and means of escape in case of fire. You may need to have "means of escape windows" especially upstairs or from rooms that do not have direct access to a hallway or external door.

You need to consider the means of cleaning the windows - can a ladder be used outside by a window cleaner, or will "tilt and turn windows" be better. Can the customer reach the windows to open them?

Do the regulations apply to new doors?

The same regulations apply if more than half of the door and frame, including the fanlight, is glazed. Any glazing in the door or door side panel should be safety glass, unless the panes are less than 250mm wide.

Care must be taken with the threshold of the door. The upstand can be dangerous and this should be discussed with your customer. An upstand can be particularly difficult for people with wheelchairs and pushchairs. Many modern homes have a ramped or level entrance and in these cases a door threshold with an upstand should not be used.