Windows and roof

With the weather getting worse, it was becoming annoyingly urgent to get the build finished. The next big task was to fit our box-section metal roof. This arrived ready cut to length , but some lucky person still had to get on the roof and fix it down. That turned out to be muggins.

We went with a "warm roof" design which more or less mirrored the construction of our walls, only with roof sheets instead of cladding. The sheets were fixed on with self-tapping screws which have a little neoprene washer to stop water getting under them.

Roof done and it was time to fit the door and windows. This turned out to be surprisingly hard. The main problem is that there doesn't seem to be a lot of information out there on how to fit windows in timber-framed buildings - all the DIY guides assume you're building in brick, which to be fair is the default for the UK. Even the ultra-detailed Irish Vernacular website (which gives step-by step instructions on how to build a small timber-framed family home) just says "see elsewhere for window details"


The windows themselves were pretty easy to install (it's simple to pop out the glass from most UPVC windows, which then lets you screw the window frame to the wall timbers).

The silver stuff round the windows in the picture above is bitumen-backed flashing tape, which we put round the edges of the window frames prior to fitting the windows. In hindsight this was a mistake, as it made our windows an extremely tight fit, and didn't really contribute to weatherproofing as water can just get down the sides of the window frame.We also found that you can't use silicone sealant with bitumen products, but luckily there's a product called "roofer's sealant" that does work, so we used this to close up any gaps at the edge of the window frames.

We fixed our window trims to the edge of the frame, but spaced them out slightly so they covered the join between the window and the wall.

The top bit of trim was fitted at a slight downwards angle to let water drain off it, and covered with flashing tape.