Insulation around windows ?

Rod in Forfar · Aug 29, 2022

I did a bunch of 26 windows in an Edwardian brick house and the worst part of the job was stripping the caked white lead paint from the outside of the window casings 25 feet above the ground. I experimented with the windows and foam by pinning them in place with #8 Robertson screws into the casings before the thermal pane inserts went in. The six screws remained adjustable as the foam set with the windows in place, and if a window section acted tight I could correct it with a bit of screw pressure before the foam set. Ten years later, the windows all function as well as they did a week after they were foamed.

I didn't use aluminum flashing at all on the outside, just a few wooden fillers and a bit of moulding specific to each window, and a fair amount of caulking. It's handy to have the shop nearby with a shaper with a lot of cutters and a good supply of pine for the purpose.

Softrider · Aug 29, 2022

When I replaced all of my windows with quality vinyl ones, I used minimal expanding door and window foam. To help prevent distortion of the frames I put three horizontal beads of foam on each side of the window, inserting straw to outside wall and slowly withdrawing, one in the middle, other two about a foot from the top and bottom. I came back the next day, with the foam set and helping to hold the window frame position I filled the rest of the gaps. This worked well for me with no window frame distortion,.