This brings me to the point where I need to install all the windows first so that I can install the flashing to go under the cladding.

I am starting to look at the vintage windows I bought 8 years ago for this project.

These windows are very well made but will need a lot of TLC to strip and paint them and to restore the balance mechanisms.

The first window I looked at has a broken coil balance spring.

I might be able to find enough mechanisms from this period but if I am going to all this work I would prefer to install something new.

The coil balance lives inside a metal container with roughly the appearance of a tape measure.

The housing for the spring is installed between the outer window timber and window cavity studs.

The coil itself emerges from its housing and runs up and down in the window jamb next to the sash and takes up about 1 mm of space.

I have viewed a few U Tube videos on how to replace them and it looks like the modern versions are quite different and need maybe 15 mm of space in order to run next to the sash.