How tightly should double glazed windows fit?

[SpottydogDomino]

We are having new d/glazed windows fitted. We don't want to piss off the builder!

One of the new windows is fitted snugly to brickwork top, bottom and one side. The other side is about 4 inches shy of the brickwork which the builder has filled with expandable foam. There will be a upvc trim to hide this.

Is this "normal" or has the builder mis-measured? And, more importantly, will be have a cold wind blowing though the foam in the winter.

Not sure whether to ask the builder to change the window or if this is normal and we are worrying unecessarily. The builder is not back until Monday so we have some time to think about it so any help would be appreciated.

Might be that the opening is not square but the window is?

The window is probably miss measured, the expanding foam is the proper way to fill it (many builders wouldn't bother) and actually expanding foam transfers less heat than brick.
He would need to plasterboard the reveals up to the frame and make good on the outside too including sealant, so you can't see any foam. Make sure he will do that.

4 inches? That's loads! I'd want a new window.

Thanks. We felt it was too much of a gap between upvc window frame and the brickwork. Plaster board may be good for the inside but the outside is brick so not sure (other than a trim being fitted over the foam) how the builder will get over the gap. Glad to hear we will not risk a massive cold draught coming through this winter.

I may approach the builder to see what he says.

Obvs I would prefer the upvc to fit snug (ish) to the brickwork on all sides so I know that it is screwed in firmly.

I just wanted some comments before I have that awkward conversation.

Yes, it sounds like a mis-measure to me. I can't speak to any technicalities here but aesthetically, I would be bothered by the lopsidedness of the window - with the gap all to one side, won't the UPVC be much wider that side? Wouldn't it have been better to fill both sides and put it in the middle so it was even?