uPVC Sash Windows installed - gaps either side of windows

[mattyb_uk]

Hi All

I was hoping for some advice here. this is less of a DIY and more of an advice issue.

We've had 3 of our old Box Sash w/aluminum windows circa 1990 removed and replaced with uPVC Sashes. The choice for this was mainly cost.

The windows were fitted by an approved installer of the the manufacturers.

The thing is - we now have 10cm gaps between the window and the brick on the inside of the window either side of each window.

I've been told to use expanding foam to fill the gaps, but I've been advised not to by the window company, as it could make the windows bow.

Does anybody have any ideas on what to put in there instead? Should we use wooden battens to pad out the gaps?

Please let me know if you need more information and/or pictures.
matt

[aeyres]

So long as there is an external weather seal & the windows are sufficiently fixed, using expanding foam should not cause any problems. I would recomment the 'gunnable' foam as this gives you much more control on application. (little bit more expensive, but worth it)
Only fill the required gap about 30% and the foam will slowly expand.
(Always easier to add more foam later, than watching masses of foam expanding around your frames!)
Finally, cut away any excess & fix some PVC trims to cover the areas.

One thing i would add is that you should be complaining about the installation as the internal finishes should have been taken care of by the them!

If you still don't fancy using the foam, any insulating material can be used, and again simply buy some PVC trims internally to cloak the gaps.