Building Sash Windows – Part 1



On my first batch of windows I used Johnstone’s Flexible Primer Undercoat and Johnstone’s Flexible Gloss. It’s not cheap but it came highly recommended by people who have used it and I would be happy agree with them and say this is good stuff. The data sheet claims an 8 year life time which I think is probably possible but only in an ideal situation. My first batch of windows has two that are south facing and really catch the elements and one that is north facing but doesn’t get a good breeze to keep it dry. After 18 months the south facing windows are showing the first little signs of wear and tear. I think I’ll be rubbing down and re-coating after 5 years but that’s as good as I think you can expect. What I really liked about this paint was how easily it went on with a good brush, an absolute must for something fiddly like windows.


I have no dealings with any of the suppliers on this list other than being a happy customer if that should ever change (unlikely I think) I’ll add a note.

  • Sash Upgrades – – Good range of sash window products including cills. Prices are reasonable and the products are generally good quality.
  • Woodshop Direct – – Limited selection of timbers but they have a machining service and will deliver for a reasonable price. For machined timber the price is quite reasonable. For my first batch of windows I asked them to machine to the exact size which was a mistake, ask for a couple of mm over size and run it through your thicknesser.
  • Wealden Tool Company – – The best place in the UK to get router cutters. Matched cutters for the window bars are available in a limited range of profiles (I think you can get customer made cutters but they would be expensive).
  • Workshop Heaven – – Top quality hand tools but expensive. You’ll need a few hand tools and considering how much you are saving you might as well get good ones.