Window size regulations

Hi

I am planning an extesnion off the kitchen to create a garden room.

I see loads of ideas etc on the net and TV - use of large glass windows and doors etc. Thats exacttly the way I want to go.

BUT my BCO has just informed me that the window cant be bigger than 25% of the new floor area. This area is 12.75 sq m. This gives me a poxy 3.125 sqm of glass!

How do all these trendy extensions get away with such big areas of glass. There must be another way?

Any help?

Cheers

Crakkers

You compensate with additional energy saving measures elsewhere in the house and then have a SAP calculation done to prove that the heat losses through your big windows are not resulting in any more energy use than smaller windows and no energy saving measures elsewhere.

The BCO has told you half the truth. You can have the windows as big as you like but you must compensate for the additional heat loss elsewhere. The standard method is to have SAP calculation carried out which shows the proposed extension showing equal heat loss to one which has windows no greater than 25% of floor area.

To the 25% of the new floor area created, you add the areas of any windows or doors that will no longer exist, or be covered over by the new extension.