gap around replacement window

[philplumber]

Hi, I've recently had my sash window replaced, which has left me with this gap to make up.I was thinking thermalite blocks up the sides, but was wondering what would be the best way of filling in across the top. Their is an existing wooden beam across, which i don't want to remove. Could i span 4x2 across, resting on theralites, then plasterboard over? View media item 74723 View media item 74724 View media item 74725 View media item 74726

 

[loply]

If I were you I'd take this opportunity to make a flared window, they look nice and let loads of light in.

Not keen on windows set that far forward in the elevation though, they look unnatural from the outside.

 

[ree]

Perhaps its the pic but you dont appear to have an outer lintel, the bricks appear to be sitting on the frame?

The inner lintel (your wood beam) seems to be two lengths pinned together? What condition are their bearing ends in?

Do you have two kinds of insulation?

Lower down the wall, is the removal of plaster anything to do with the window renewal?

The suggestion above is for splayed reveals.

 

[catlad]

Celotex, expanding foam, then plasterboard over.