Damp on internal wall around doorframe

[jbwilliamz]

Hi,

I've always had a minor issue with damp on the gable end of our 1960's house. Recently, I managed to get the insulation removed from the cavity on the gable end through the CIGA guarantee. It's a south facing gable in a coastal Welsh town so took the brunt of all the weather.

Forward on 4 weeks, I've painted the internal wall with a damp proofing paint along with the external wall. Recently I've noticed that the paint is bubbling in locations and failed in others. This is mostly around the door frame/reveal. The location of the damp issue seems to follow the same profile as the angle bead on the corner of the wall.

I'm starting to run out of ideas as to what the cause of this could be and I'm tempted to get a builder in to reconstruct the cavity closure with a new vertical damproofing around the door frame.

I was wondering if there were any other suggestions to the cause and possible fixes?

 

[^woody^]

Does the door frame cover the DPC between the external and internal leafs - it may be too far forward?

 

[jbwilliamz]

Not that I can see. I had to remove the upvc corner details by the door frame along with the skirting boards because they were ruined. You can just about make out the vertical DPC on the middle photo, but it's also not in great condition. It's friable and breaks up if you grab it. Although I'm not sure how the damp isn't on the wall closer to the door rather than on the internal edge?

 

[tel765]

Its recom that all frames should be set back a min of 75mm from the face of a residence - how far back is your frame set?
Is the floor solid?
Is this the wall where the CWI was removed from? Was all the insulation removed - how do you know? What kind of CWI was removed?
Besides the exposed location - were there also any damp issues with the CWI?

Whatever is in the middle pic its not DPC material.
DPC material is not friable - perhaps the corner beads have been replaced at some time, and whats showing is paper tape? Metal beads will soon rust out.

You say you have used waterproof paint on what we can see in the pics?

Can you look at the wall behind the base unit runs - look for dark stains like the marks above the frame head?
Can you post pics of the outside wall and outside threshold sill?

 

[^woody^]

DPC material is not friable

It is if it's bitumen based

 

[tel765]

Fair enough.

 

[jbwilliamz]

Its recom that all frames should be set back a min of 75mm from the face of a residence - how far back is your frame set?
Is the floor solid?
Is this the wall where the CWI was removed from? Was all the insulation removed - how do you know? What kind of CWI was removed?
Besides the exposed location - were there also any damp issues with the CWI?

Whatever is in the middle pic its not DPC material.
DPC material is not friable - perhaps the corner beads have been replaced at some time, and whats showing is paper tape? Metal beads will soon rust out.

You say you have used waterproof paint on what we can see in the pics?

Can you look at the wall behind the base unit runs - look for dark stains like the marks above the frame head?
Can you post pics of the outside wall and outside threshold sill?

To the front of the door is around 35mm set back from the outside wall.
Floor is solid, yes.
Yep, we only took the cavity insulation out on that elevation on the recommendation of CIGA. The insulation was the pink fluff (glass wool?) and it was clear after extraction. There were some issues elsewhere, but they haven't come back as of yet.
As mentioned, it was bitumen dpc. Although when we had the kitchen renovated, the builder put a new dpc in around the door - although it doesn't look like it's working.
Yep, the white paint is the damp proofing paint.
I can't get to the back of the units unfortunately, but there isn't a smell of damp in the cupboard.

More photos

 

[^woody^]

That's an unusual place for damp ingress to show.

Damp proofing paint or anti-condensation paint? Probably does not matter though as either will just seal in any damp, or any salts created by previous damp and cause the paint to blow.

In addition that paint may well prevent the tale-tale brown staining and white salt staining that would be visible and expected if there was penetrating damp from the door jamb.

I'd scrape that paint off and let it breathe for a while and watch for any damp ingress, it may be that just the plaster needs replacing and wall neutralising to deal with any salts. Otherwise if there is a damp ingress issue at least you will then see it

 

[jbwilliamz]

That's an unusual place for damp ingress to show.

Damp proofing paint or anti-condensation paint? Probably does not matter though as either will just seal in any damp, or any salts created by previous damp and cause the paint to blow.

In addition that paint may well prevent the tale-tale brown staining and white salt staining that would be visible and expected if there was penetrating damp from the door jamb.

I'd scrape that paint off and let it breathe for a while and watch for any damp ingress, it may be that just the plaster needs replacing and wall neutralising to deal with any salts. Otherwise if there is a damp ingress issue at least you will then see it

Yeah, it's got me stumped.

It's the Polycell damp seal paint. Two coats. That's the other option I'm considering; taking the angle beads out and replacing them and any localised damaged plaster. You're right though, where the paint has failed, it's the salt/efflorescence that's come through.

The other thing I noticed whilst it's been particularly wet recently is that in the third photo on the opening post where you can see the hole near to the door, is that when I put my hand in there (through to the cavity) the back of the return is very wet, not the outer skin but the return from the door?!

 

[tel765]

Given what you say about a wet cavity & the damp damage to be seen in the pics maybe you should remove the beads and the plaster back to masonry on either side of the doorway.
As above, the seal paint is irrelevant and has already blown.
So the beads and plaster will have to come off at some time.
With the reveals exposed you will be able to see how the the cavities have been closed.

Outside to the right of the doorway there are three large air vents, all set high to perhaps hopefully help somehow with damp on the inside wall - or they might be the remains of the CWI removal openings?

 

[jbwilliamz]

Yeah, that was my original thought. Looks likely I'll have to go down that avenue.

There's two "air vents" which have 6" cores through the wall covered with the plastic vents. Not sure what the original purpose of those were - they only come through the outer skin, but they were there when we bought the house.

The CWI was installed and extracted through the same 1" (roughly) holes evenly spread across all elevations on the house. They've all be closed up after the extraction.

 

[JohnD]

looks like rain penetration to me, unless water is dripping down inside the cavity and pooling on the lintel or doorframe. Are there pipes, bathroom or old gutter above? Edge of the roof in good condition?

You could experimentally rig up a flap of plastic sheet above the head of the door to confirm that rain cannot reach it.

Does the wetness vary with weather? Or the number of baths you have? Bathwater can usually be detected by the scent of shampoo, bath foam etc. Tapwater has no scent but can be identified by the presence of chlorine and (sometimes) hardness.

It would be a pity if you discovered the CWI was not to blame and you have a leak.

 

[tel765]

Brickwork, say min of 5 or 6 bricks, should be opened to remove CWI. Openings in various places at the base of the walls.
With the reveal cavities opened you will be able to inspect the elevation cav's for rubble bridging or incomplete Insulation removal.
You would also be able to see any cavity trays over GF frames.
Maybe the core drilling was done to an old discounted method called venting the cavity? Anyway - remove the covers and make good the brickwork.

 

[Nige F]

Maybe the core drilling was done to an old discounted method called venting the cavity? Anyway - remove the covers and make good the brickwork.

Or remove the covers and use the holes to inspect the cavity - replace them and save yourself a lot of work

 

[dontbelieveawordofit]

With the reveals exposed you will be able to see how the the cavities have been closed.

therein lies the problem. seen loads of houses like this where the cavities are closed with brickwork or timber blocks to give original wooden frames a fix.