I won't pretend for a moment the decision to make the windows isn't driven by cost. At a very minimum it would cost 15 grand (sterling) to buy these - supply only. I could replace the windows for less if I went with upvc pretend sash windows, but they are by their very nature, odd and cheap looking and I don't want that. They need doing. All the tools needed to make these are there, just sitting idle. I know my capabilities and limitations. I have the time to make them and can do it for about a third of the cost. I could buy a new motorcycle with what I save when they are all completed. This is my decision making process. The die is cast.
Those don’t look as if they’re beyond hope yet, so one thing you might consider is stripping them, firming up any rotted wood with wood hardener, then repainting and reglazing them. I did a similar thing a few years ago and wrote it up. Wasn’t too bad, and kept me from having to completely rebuild things.
Believe me, the windows are beyond saving. I have previously tried thin consolidating epoxy and filler but I'm not happy with the way that turned out after a few years. There is so much weathered timber in there that I don't have confidence in the paint sticking, even with specialist primers. This is an upgrade project as the windows are single glazed, so they are noisy and not energy efficient, they don't have any draught proofing either. If I did just double glaze and draught proof what's already there, I would still be into a hefty chunk of change. Making new sashes and frames will probably add about another third of the cost of the glass and sundries, based on 6 windows in progress - glass and draught proofing, new spiral balances etc approx £1200 timber coming in so far at under £400, so for my own peace of mind, renewing is the way to go. Plus it will be a lot easier doing this on a bench rather than in situ.
A challenging project, windows are fun to build. Did a custom one years ago, a large diamond shaped one 7' wide and 3' tall with 25 individual panes. It was for a gable in a old 200 year old farm house..
