Bung:

timmmay:

 

A builder friend quoted $3795 to remove the window, replace with weatherboards, insulated, gib, and plaster but not paint. In the past I did find a builder who would've done the building work for $2K, no plastering or painting. There are fairly strict building codes now.

 

I have no idea whether $3800 is fair but I don't think there are any real differences in the standard of work required except insulation in last 70 years for that sort of change. Too many things are blamed on Codes or H&S.

You'd need a 20mm drained cavity space between the back of the weatherboards and the building wrap plus the insulation on a new wall that wouldn't have been required 70 years ago.

So the codes have moved on.

Although to be fair, you might get away without if it's infilling a localised opening and you're matching the existing construction.