I've just been to see a job. A house that has about 10 windows (exterior) that need re-painting. Obviously I won't be painting them in this weather. The windows have a satin finish on them so I asked the owner if he had the old tin, the tin was the Dulux Satinwood - oil-based. I thought this stuff was just for interior use? Could this be the reason why after only 1 year the windows are peeling?