Velux Window wet patches

[Nicola Davis]

Can composite tiles cause excess condensation?

 

[catlad]

Yes

 

[datarebal]

cement fibre slate, not my favourite product but they are usually reliable. Batten looks pretty wet . are there pictures showing ridge detailing?

 

[bobasd]

OP, you show a means of photo'ing the roof which is good - because after all this traipsing back and forwards on them fragile tiles you should take a number of context and detail pics of the final result.

OP, you are reluctant to remove the water damaged plaster board as i suggested.
you will have to remove it eventually for fresh decoration and the removal maybe of sodden insulation.
when the p/board is off - leave it off until the roofers claim the job is finished. then you can observe if the Velux'es and roof is indeed watertight.
the costs of making good the insulation, the p/b and re-decorating are down to the roofers not you.

OP,, you could always approach the Velux Tech dept with your complaint and pics?

 

[bobasd]

datarebal, we no longer work installing or repairing Eternit etc roofs - even with cushioned roof ladders there's always a chance of cracks or worse.

 

[Nicola Davis]

I’ve just found another forum (Screwfix forum) where someone else had exactly the same problem as me and the wet patches in exactly the same place and it appeared that no gutter was installed above the velux which lead water to seep in. I think another call to my roofers. I have also emailed velux so thank you for the pointers. I have 4 velux windows with all the same problem.

 

[datarebal]

datarebal, we no longer work installing or repairing Eternit etc roofs - even with cushioned roof ladders there's always a chance of cracks or worse.

Don't think they are eternit.
That aside,the moisture appears above the underlay then finds its way around the velux by incomplete underlay fitting.
But as the underlay is not the source of weather proofing . We need more info, finished ridge detailing pictures and the measurement of exposed slate bottom of one slate to the bottom of the next .

 

[datarebal]

I’ve just found another forum (Screwfix forum) where someone else had exactly the same problem as me and the wet patches in exactly the same place and it appeared that no gutter was installed above the velux which lead water to seep in. I think another call to my roofers. I have also emailed velux so thank you for the pointers. I have 4 velux windows with all the same problem.

 

[datarebal]

Email the covering tech support ..
There should not be that amount of moisture getting to the battens. On to the underlay
Exact pitch will be required , it's not 45. But looks ok

 

[Nicola Davis]

Thank you much appreciated for your help.
I think also after researching and seeing how velux’s are fitted that it’s the insufficient fitting of the underlay as it should wrap around the bottom batten and mine doesn’t. This is the correct way


This is mine and it doesn’t look like the breather membrane has been lapped over the batten.

I’ve a dry ridge system but have vents at the bottom of the soffits.

 

[datarebal]

Yes I can see the underlay isn't dressed correctly.
But the point here is the underlay is not the main source of weathering.
You need to nail the source of moisture not just rely on the underlay which won't last that long , even a decent one like yours.
By the way soffit vents will not vent above the veluxs

Your quest is not over

 

[Nicola Davis]

No it’s not over and I wish it was .... points noted from your comments, over to Velux now for them to hopefully come to a conclusion.
Many thanks for your advice & comments everyone.

 

[Nicola Davis]

Hi again,

I’m back on this forum as my nightmare damp patches are back, nothing at all in the summer (warmer/mild) weather or when it rains but now it’s getting colder I have my nightmare back. The damp patches only occur when the weather turns cold, I’ve had a BFX collar and transverse drain fitted to just 1 velux to see if it makes a difference and I’ve still got the same problem. We have stripped away the plaster around 1 velux window insulated around it and if I push my hand up around the head of the velux the water is piddling down my arm. I’m at a total loss as to why this is happening, I’ve had the velux technical out/ my roofers out and a surveyor out all at the same time, and the conclusion they came to was that I have a cold bridge. The BFX collar and transverse drain should have stopped this surely as that is what the velux technician recommended.

Has anyone else had this problem at all and managed to rectify it? The insulation we used for our roof was Actis Hybrid and a vapour barrier blanket stapled over the top if that’s any help , all Actis.

Any one please help I’m at a total stressed loss.

Thank you

 

[catlad]

Who supplied the materials, who's design was it, who was project manager?

 

[Nicola Davis]

We had a reputable roofing company supply the roof materials along with the velux’s, we didn’t have a project manager as such we purely relied on each trades professionalism and expertise for each part of the job. We did our own insulation with guidance from Actis themselves, they also came out to check all the insulation was installed correctly, also this is only happening on one side of our house the other side is absolutely fine, which leads us to think that it not the insulation causing the problem. I’ve uploaded a photo of me sticking my hand in the area where we have ingress of water/ condensation also I can feel a metal rim around the edge of the velux surround where it sits inside the rafters, the metal is drenched.