Velux do the traditional centre-pivot type and also top-hung windows. Two related questions:

1) In their brochure they list the sizes of the top-hung windows which are suitable for escape (450 mm high and wide and 0.33 m² opening - same in England and Wales and in Scotland as far as I can see) but they don't list the same for any of the centre-pivot ones though obviously the larger ones can meet the requirements. Any ideas why? (other than maybe they want to sell the more expensive top-hung ones).

2) My design has six roof windows (it's an A-frame) and one gable-end vertical window. Am I mad to consider, for simplicity, just using Velux or the like for all seven windows? Top hung have a max angle of 75° so wouldn't be suitable for the gable but centre pivot are listed as suitable for 90°.

(The room with the gable window is the main bedroom which is the room furthest from the front door so it obviously needs a means of escape. It has two windows, one on the south roof slope and one to the east in the gable. The roof window could be the escape window but as currently designed has a solar thermal panel below it which would not be good so I'd assumed use of the gable window for escape.)

also WRT the escape window, it would have to be the gable window, not the sloping one. The sloping one would probably fall foul of the regulation requiring it to be a certain distance from the eaves.

The best person to speak to would be your building inspector as he would have to sign it off anyway.

As for vertical mounting of a centre pivot window, I don't see why not, especially if the gable was tile hung.

Bear in mind the regs about the min sill hight for upstairs windows.

Also VELFAC are VELUX's sister company for "normal" windows. They are very good (I have some). They specialise in alu clad timber frames.

Yes, eaves are about 400 mm above ground level.

I have seen something somewhere about distance of sill from eaves but can't find it in the Scottish Domestic 2010 handbook so not sure where - English rules?

The distance of my sills from the lower edge are set pretty much by the height of the solar thermal panels (just over 1600 mm). Roof slope is 60° and it covers 400 mm deep floor so about 1000 mm above floor height which works out just fine - well over the minimum of 600 mm and just below the maximum of 1100 mm.

Gable will have solar warm air collectors so will be clad with twin-wall polycarbonate. I think that can be made to fit with the window flashing OK.

Will look into Velfac.

Posted By: Ed DaviesI have seen something somewhere about distance of sill from eaves but can't find it in the Scottish Domestic 2010 handbook so not sure where - English rules?

Defo a Scottish rule. The lowest open part of the window no more than 1.1m above FFL. Min opening must be 450x450 (allows Firefighter with BA access I believe). That is a vertical measurement not the sloping size.