Window set back

[benben5555]

Any thoughts on how far to set back windows within the reveal of a timber framed house? We have areas of brick and areas of timber weatherboard.

[nod]

I normally leave 50 mil of brick showing 

[Dave Jones]

the ideal place to set the window is so that it is encapsulated by the insulation, building regs like to see a min of 65mm now unless you plan on insulating the reveals inside separately.

[benben5555]

I'd prefer not to insulate the reveals if not necessary. The below is a 60mm set back, what do you think of this arrangement?

[Dave Jones]

its going to work fine but it wont perform its best, could look at insulated wood fibre board for the reveals as its not so deep, or aerogel insulation but the latter is ££££

 

It's worth getting as much insulation as you can now as the finished window will lose heat forever after fitted so the more can you mitigate it the better in the long run.

[Mr Punter]

You need to move it inboard a bit.  If it comes in 30mm and you seal it to the timber stud you will prevent any outside air getting behind the reveal plasterboard and into the service cavity.

[benben5555]

I was thinking about having the timber frame built slightly wider to allow for some insulation in the reveal, but if I do that and set the window back there is going to be nothing to fix the window to.

 

If I set the window back another 30mm and then strap fix the window to the stud I could line the reveal with 25mm insulated plasterboard. How does that sound?