Velux window - damp

[Peter2222]

Hi all,

We have Velux windows installed, and about a third of them all have water ingress when it rains, in the bottom left corner of the frame.

Some are worse than others but it's after heavy rain, and starting to rot the wood in places. I can't figure out why as the other corner is dry and looks the same otherwise.

Anyone experienced this before? Know of any fixes? Before I resort to calling a velux specialist round (don't wanna pay a fortune for replacements).

Photos attached, one of the wet corner, the other of the dry corner.

Thanks in advance.

 

[blup]

Is the glazing not properly sealed in the wet corner? Pics of windows as located in the wider roof would help.

Blup

 

[Peter2222]

Is the glazing not properly sealed in the wet corner? Pics of windows as located in the wider roof would help.

Blup

I can’t tell any difference between the outside casing. Attaching the left (wet) and right (dry) for comparison. Any ideas??

 

[blup]

Water can find its way through almost invisible gaps. If you can get up there try removing and checking under the profiles where they meet the glass, the seal/sealant under them has probably perished or was inadequately applied.

Blup

 

[Peter2222]

Water can find its way through almost invisible gaps. If you can get up there try removing and checking under the profiles where they meet the glass, the seal/sealant under them has probably perished or was inadequately applied.

Blup

Thanks Blup, yeh I feared something like that - probably a silly question, would it be worth just blasting some see-through silicone over the top of it? I cant get good enough access to remove the profiles but can probably get a gun to it

 

[crank39]

Under that tin flashing there is a strip of chewing gum type seal that will take multiple passes with a new stanley blade if you ever wanted to remove it, i've done plenty while replacing DGUs in velux's and can say if its the original glass then they are pretty much well sealed in that area

 

[Peter2222]

Under that tin flashing there is a strip of chewing gum type seal that will take multiple passes with a new stanley blade if you ever wanted to remove it, i've done plenty while replacing DGUs in velux's and can say if its the original glass then they are pretty much well sealed in that area

Thanks Crank - it is the original glass but 20 years old, so even if I tried I'd struggle to get the flashing off? So only option (other than getting someone more qualified in) could be to seal over the top with silicone?

 

[blup]

Thanks Blup, yeh I feared something like that - probably a silly question, would it be worth just blasting some see-through silicone over the top of it? I cant get good enough access to remove the profiles but can probably get a gun to it

You could and it might work but its a bodge, removing the trim will indicate where the water trail is.

Blup

 

[blup]

If its a ground floor roof, a scaffold tower would help with access.

Blup

 

[catlad]

Normally on that age of skylight the side trims have come loose. Once you have the skylight fully open the side flashing is the long strip down the side held on with 3 screws, if you remove one screw at a time and wrap the screw with some p.t.f.e. tape and replace, this should seal it better.

 

[Peter2222]

Normally on that age of skylight the side trims have come loose. Once you have the skylight fully open the side flashing is the long strip down the side held on with 3 screws, if you remove one screw at a time and wrap the screw with some p.t.f.e. tape and replace, this should seal it better.

This makes sense.. thanks, I will give it a go

 

[Peter2222]

Normally on that age of skylight the side trims have come loose. Once you have the skylight fully open the side flashing is the long strip down the side held on with 3 screws, if you remove one screw at a time and wrap the screw with some p.t.f.e. tape and replace, this should seal it better.

Is this the side flashing that you think could be the problem? I can only see one screw so not sure

 

[crank39]

Yes take that screw out and slide the tin flashing up to release it, then you'll expose 3 or 4 screws that hold the tin that holds the glass in place, this is the one that's held down with chewing gum

 

[blup]

Ptfe, or mastic on the screw and in the hole.

Blup

 

[SpecialK]

You can remove the glass part and bring it inside to play. However ... if its a large window they can be very heavy...