i know that wood can have issues, but these where on upvc windows, on modern houses.
i think it will be a matter of me slowing down a bit, and making sure to rinse thoroughly.
is it ok to leave water on the frame that will obviously eventually drip down, as long as it is pure water from lots of rinising?!
another thing, the weather here has been warm, very sunny and quite breezy, would that have an effect?