Leaking velux

[nutterbutsquash]

We had a velux installed last month and in very heavy rain it leaks. The rain will start and nothing comes in, and then all of a sudden, it just flows in like a tap has been turned on.

The builder has been back to try and fix it but hasn't been able to and says we need a new roof. This seems pretty extreme especially as the roof wasn't leaking before the velux went in.

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We had another roofer come round who tapped a tile back in place to see if that resolved it but it hasn't.

Any ideas?

THanks!

 

[Roofer]

Is the leak at the top or bottom of the Velux?

Have you got any pictures of how the front flashing has been installed/dressed?

 

[nutterbutsquash]

The leak starts at the top left (looking at it from inside) and this is where it gushes in. There is a smaller drip from the bottom left but I think this is where it has gone down the frame rather than coming in from outside.

sorry to ask a silly question but what is the front flashing? Would that be the the bottom of the window?

 

[Blagard]

Was it an actual Velux or another make ? If you can get information on the actual roof light itself, model number would be ideal. Installation at the top right (outside) just does not look right.

The job is not right if it leaks, so you may need to warn the builder that he needs to finish the job properly or you will get some-one who can and sue him, including costs for remedy to damage caused.

Just to be sure, did the builder get all the materials for the job himself ?

 

[nutterbutsquash]

It was a Velux, we bought it along with the flashing kit. The timber for the frame was also supplied by us and the builder bought the felt.

The builders view is that it's the roof that is at fault, not his installation.

 

[Blagard]

It was a Velux, we bought it along with the flashing kit. The timber for the frame was also supplied by us and the builder bought the felt.

The builders view is that it's the roof that is at fault, not his installation.

At the moment I certainly would not agree with the Builder that the roof is at fault. However if you asked him to fit what you bought, the next thing is to find out is if you bought the right things. What were the Velux part numbers of what you bought?

Edit: Also were both the window and the flashing kit new? A photo of the complete window (outside) would be useful.

 

[nutterbutsquash]

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This shows the bottom, I can't get a view of the whole window as it's 2nd story.

We have since had another roofer come round and adjust an out of place tile to see if that fixes it - it hasn't.

Both roofers cannot see anything too wrong with the installation. The first suggested that we refelt and retile whole roof, 2nd thought tiles were fine, just needed a refelt.

I can't understand why we wouldnt' need to retile if water is getting onto the felt. And is water does get onto the new felt, won't it still leak through the window?

Really confused and just want this fixed so we can get on with finishing the work up here.

 

[nutterbutsquash]

Both the velux and flashing kit were new, fresh out of the box.

 

[noseall]

Those tiles look horrific and not a whole lot of head-lap either.

 

[Blagard]

I had a look as one of the velux section drawings and it shows profiled tiles overlapping into the side gutters of the roof light, yours do not. I am not certain this applies to your particular roof light as you never came back with a model number or the flashing kit reference.

 

[nutterbutsquash]

Sorry for the delay, here are the model no.s

window - GGU 0059 M04
flashing - EDW 0000 M04

 

[catlad]

think blagards might be onto it there. I have not seen that profile before and I think the tiles could have been cut better for that profile

 

[Blagard]

I looked at a number of drawings including one with the GGU window and the EDW flashing. On the basis that the problem is not the window itself I looked for the detail that most closely resembled what you should have and found that example in the link below. I appreciate this one is a GGL window but the flashing is the same and the tile profile as irregular as I could find.

You can forget about the insulation aspect of it, You need to concentrate on the way the product keeps water out. i.e. the flashings and window itself

http://www.velux.co.uk/en-GB/Docume...roof window installed into profiled tiles.pdf

It is the seals between roof tiles and the flashing that make me wonder if they have been installed correctly. The tile itself is a nasty profile because there is not one place on the underside of it that is flat to get a decent flashing to tile seal except perhaps the underside of the high point.

The fact that you refer to the water gushing in and that this occurs at the top also makes me wonder just how well the top side detailing has been carried out. I would at a minimum expect to lift the tiles around the head of the window to be sure it is correct.

You may need to get some-one to remove tiles and inspect the work more closely

other drawings I looked at are:
http://www.velux.co.uk/en-GB/Docume...e-pivot installed into interlocking slate.pdf
http://www.velux.co.uk/en-GB/Docume...HL top-hung installed into profiled tiles.pdf

 

[jono_h]

The Velux instructions also show that the felt should be sealed to the side of the window, using their own under felt collar or standard felt. This prevents any water that does get under the tiles from coming inside.

I know that the builders that installed my Velux's didn't bother and just cut holes in the felt and stuck them in. I got away with it on 4 units, but 1 leaked and I had to strip back the tiles and make good.

http://www.velux.co.uk/en-GB/Documents/Installation instructions pdf/BFX 1000 - 450764-0308.pdf

Obviously the best solution is to stop the water getting under the tiles in the first place, but fitting the collar maintains the secondary protction of the felt.