Velux Window wet patches

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Hi

Just wondering if someone could help with any advice regarding wet patches on plaster that keep appearing around my velux windows.

The patches seem to mainly appear after it’s rained but not necessarily all the time. They appear in the same place then dry out and reappear even if it only slightly drizzles with rain, the velux windows have been fitted to a 43 to 45 degree pitch roof with (can’t exactly remember the exact pitch) with composite flat tiles. I’ve popped my head out the velux to see if I can see anything but all looks okay to me. The velux have been fitted with the plastic flashing kit (not sure exactly what it’s called) so I’m at a total loss as to why this is happening. I’d be grateful of any advice or anyone else that has had this problem and managed to come to a resolution.

I don’t think it’s condensation as I’ve had my hand up behind the insulation and it’s bo
Pics attached.

Many thanks
 

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not much to tell by these pictures. The issue is outside. take some to the rear of the velux looking up the roof to the top and also immediately to the rear where the roof covering laps the back gutter..
 
Something not right with the flashings is the obvious thing. An inspection outside is the only way to tell. Looks like the flashings at the top of the window if I am interpreting the photos correctly. I have come to that brilliant conclusion because the damp patches appear to be at the head of the window.
 
as above.
badly installed flashing seems to be a common problem with these lights.
OP, why not fix your camera to a stick, set it in video mode and search above the frames as suggested by datarebel?

given you will have to eventually cut out and replace some of the plasterboard then why not cut it out now and try to see whats happening from inside and below the kerb?
 
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Hi we had our roofers out and they took out the velux and around the area of the velux the breather membrane and roof battens were soaking wet. Roofers said it is condensation but I can’t see how this can be, has anyone come across this problem before. We have insulated with Actis Hybris & their vapour barrier - also had them out as well and they couldn’t see anything wrong with the instalment of the insulation. We have taken some of the plaster away from around the edge of the velux and it seems to be really wet where the metal beading is that the plaster boards sits in. The roofers don’t seem to think it’s the velux or flashing! I’m at a total loss - any help or advice would be much appreciated. Also the roof tiles when taken off to get the velux out were really wet on the underneath around the velux area.
 
it appears to be far more than condensation - you have water entering the roof through the cover or the Velux.
maybe it would have helped perhaps if you had followed suggestions back in november?

anyhow, were the velux's fitted as retro frames or while installing a new roof?
who exactly installed the velux frames - the guys on site now or others?
did they supply and fix all the components incl vapour barrier?
what ref # Velux was fitted?

"they took out the velux" - do you mean the sash, the frame and the flashing?
is the Actis Hybris still i place?
likewise all sodden insulation?

still no pics of the roof and frame exterior surround?

fwiw this late in the day - it pays to only allow Velux trained installers to fit their lights.
 
All the damp seems to be at the top from the pics, is there cover flashing above where the roof abuts a wall? As above need a decent outside pic
 
The roofers installed the velux windows whilst they were doing the roof. When they came to investigate they only took out the window of the velux and left the surround in tact. I’ve attached a picture.
 

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The wetness is coming in on the photo where I have marked. The room has been freshly plastered so I am relucuctant to start demolishing it if this is a simple fix. The strange thing is though that the damp patches are appearing when it’s cold, not when it’s warm or raining!
 

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I don't see any signs of a bdx collar or trans drainage gutter
designed to stop condensation or ingress of water coming into the top of the skylight.
 
Another photo of insulation and velux.
 

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