We restored the windows on a converted convent outside Bristol. The windows had been badly damaged by wood rot and moisture gathering under layers of old paint and were in seriously bad condition.
Working with a Sash Window Expert, who rebuilt an repaired the serious moisture-damaged wood we scraped back all the previous paint. I finally restored the frames with three natural oil-based paint from Auro. First the Auro special primer- 117 then the white undercoat No 933, finally the white glossy No 935.
All the paints have a base made of Linseed Oil with a orange oil solvent. The orange oil gives off a pleasant aroma that makes this paint enjoyable to work with. The linseed oil allows for expansion and contraction and release of moisture in the wood with changing temperatures and humidity. It also has a better bond to the wood and does not crack.
Exterior conventional acrylic based paint in my experience do not move with wood and not easily release moisture. They form a hard plastic surface, with moving wood and changing temperatures cracks appear letting moisture in and trapping it rotting the wood quickly. Sometimes the rot is not viable and the paint and windows look o.k but when you push the paint there is no wood behind it, its rotten.
A large scaffold and a tower scaffold for the sides of the house were erected and we were able to restore the windows to an excellent condition while keeping the original wood and glass panes. We hope paint Job and wood will now last twice as long.