velux window exterior waterproofing

northernsoul

Hi. I have 3 Velux windows. During the winter the 2 south facing windows seemed to get soaked in water and the damp came through to the plasterboard. The outside of all 3 windows look as if they need treating. I have looked on the internet at various opinions of varnishing/treating and there is no agreement on what to use.
It would seem to me I need something that is flexible so it does not split in the sunlight and probably something that soaks into the wood.
Sadolin, Cuprinol, Linseed, Butinox paint, and Tung oil have been mentioned.
Velux, of course sell something, but its very expensive (£26) for a small bottle that looks like it could only do 1 window.
Could someone please advise as my south facing windows get a lot of rain from facing the valley.
Thanks

Furts

This sounds to me like incorrect installation leading to damp penetration. Have you got flashing kits installed with the windows? Are the tile, or slate overhangs correct? Was the roofing underlay correctly detailed around the Velux? Have you an adequate roof pitch?

These are some thoughts that come to mind.

northernsoul

Hi Furts. Thanks for that. I have had a Velux window fitter come to quote me for 2 new windows and he said he could see nothing wrong with the fitting although he thought the flashing was unusual.
They are 22 ish years old and on this model the bottom sides of the frame (the fixed part) are not covered and the wood is open to the elements. In 1996 they changed the design the cover the bottom end of the wood ie all wood now covered.
The wood did look soaked right through from this bottom end of uncovered wood. I have not treated the window for years (but did not do the outside anyway). They supply an expensive kit to cover the wood but I have made my own.
I do think over 22 years the factory water repellent has given in. As I say, there is bare wood at the bottom end sides. I cannot believe they were originally designed like this. I think in 1996 they probably knew they made a mistake.
Cant answer your questions though and I could be wrong. Thanks again.