HELP, VELUX ROOF WINDOW LEAKING.

[yamkwak]

Hi got a velux roof window GGL c04 and its leaking from the bottom corner into the room, only leaks when the rain is persistent over many hours, went onto the roof to finally try and see the problem and found that 1. The aluminium flashing cover over the wood frame rubber seal appeared damaged, I have ordered a new one £6.00. However the frame at the bottom is split. See photo's any help would be appreciated.

 

[noseall]

The split timber should not on its own cause the flashing to leak but it may need some repair glue (or similar) squirting in it to allow the flashing screw to grab.

I take it you have removed the flashing covers to allow us a squint at the split, yes?

 

[yamkwak]

Yes flashing removed for photo, I've put some PVA wood glue in the hole and the split, however I'm concerned as there is obviously a bit of dampness in that corner and I cant understand were the water can have come from?

When I get the new flashing piece should I fit it back with some sealer ? Try and seal out the water?

 

[cotswoldbuilders]

Is that a rusty screw I can see in the lower half of the flashing.

 

[yamkwak]

If you mean by the roof tile, no its just a piece of dirt. I lifted some of the roof tiles around the edge and all appeared well underneath, my concerns are the side of the velux as shown, the rubber seal on the flash covering was sort of twisted half way up the flashing near to the hinge, from there water appears to have been running down the wood?

 

[Porque223]

It took my self-installed Velux non-openable skylights six months to leak because of just the right combination of wind-driven rain. I put off drywalling the lightwell for this reason.
A roofing guy came and caulked the whole thing, this was in 1994.

Just recently I had the same problem and so this time I caulked by guesswork and it seems to have worked. I used leftover caulk because the color didn't have to match.

Unless you frequently get persistent rain for many hours it will be months before you can be reliably sure that whatever fix you use actually worked.

To find the path of moisture along the wood you might rent one of these two-prong moisture meters.

 

[yamkwak]

Where exactly did you caulk? I'm thinking UNDER the flashing along the top wooden edge to ensure the water stays out, BUT my concern is that water should not be leaking in and if Velux recommended caulking/silicone/sealer whatever they would say so, surely they should not leak.

Funnily enough I have 2 velux windows on the same roof (extension) and the other one is fine, wood edge is bone dry?.

 

[Porque223]

Where exactly did you caulk? I'm thinking UNDER the flashing along the top wooden edge to ensure the water stays out, BUT my concern is that water should not be leaking in and if Velux recommended caulking/silicone/sealer whatever they would say so, surely they should not leak.

Funnily enough I have 2 velux windows on the same roof (extension) and the other one is fine, wood edge is bone dry?.

I caulked the seam between the vertical flashing coming out of the roof at a right angle and the horizontal shingle overlap, so the water runs down the roof past the skylights rather than running under the shingles.
I should mention that I did not reshingle the whole roof after installing the skylights, I just patched into the existing roof.
I followed the flashing instructions religiously but I must have had my doubts, otherwise I would not have left the lightwell open.

These skylights cost $50K. A few hundred for the skylights and $49K to repair my hand after I ran it through the table saw (no guard on the blade, now I use a guard always).