Penetration Damp

[Krishna24]

Hi,

Recently, I bought house and found it has penetration damp on gable end. As far as my investigation goes. Source of the damp is faulty points. 

 

I have removed all plaster from the wall. Practically. I am down to original brick. I am planning to put insulated plaster board with moisture barrier. Do you think I should be mindful before applying insulated plasterboard.  If yes, what kind of treatment should I do.

 

last question, 

 

It's a solid brick wall and had paint before I bought the house. Now I found that solid wall suppose to breath. If the breathability issue comes then it will start the problem. So, I don't want to leave the wall as it is after repoint. So, what kind of paint I should use?

 

Thanks for reading my query.

 

Cheers!

[Mr Punter]

With a solid wall, adding non-breathable insulated plasterboard internally will make the wall colder and wetter.  Could you use external wall insulation?

[twice round the block]

Got any photos of the gable,

inside and out just so we know what we're commenting on.

Thank you.

[Redbeard]

Welcome!

 

I (and many others on here, I imagine) would like to steer you towards breathable (water vapour-permeable) insulants such as cork or wood-fibre (WF), but whatever you use, ensure that it is bedded in a full coat (or at very least (second-best) a full-perimeter bead with cross-hatchings) of adhesive to reduce the risk of thermal by-pass (cold air moving between the wall and the insulation). Before you do anything have a read of the government's Best Practice Guidance (Retrofit Internal Wall Insulation: guide to best practice (publishing.service.gov.uk)

Insulated plasterboard may incorporate a vapour control layer but it is missing at every joint. I prefer (if I am using plasterboard, rather than plastering onto cork or WF) to use separate insulation (say PIR) taped at all joints and perimeters with air- and vapour-tight tape, then add the plasterboard.

 

More than anything, though, if the wall has been soaked give it a long while to dry out. 225mm of brick takes a long time if it has been really wet.

 

 

Edited July 12 by Redbeard

[SteamyTea]

Our @joe90 had some wind driven water problems on his new build, he had used a full fill mineral insulation that could cope with getting wet, and treated the outside brick.

Cured the problem.

[joe90]

19 minutes ago, SteamyTea said:

Our @joe90 had some wind driven water problems

I discovered the west facing outside brick skin was wet through when drilling for the ASHP pipes, insulation had not wicked it up at all which was good but I treated the wall with waterproofer anyway to protect the bricks more than anything.

[Krishna24]

Here are some pictures of the internal and external wall.

 

When I bought the house, each wall had wallpapers and these wall paper were quite thick. After investigation I realise points has gone through first floor. So, whenever it's raining and have wind water is penetrating through. 

 

Now, I m bit confused regarding putting a layer of masonry paint. Gable end had paint and can see the some places face of the brick has blow. From research I found that it only happens when. Wall is anablw to breath and moisture is trapped. 

 

Do you think I should apply any masonry paint on gable end to stop water going through? If yes what would be the best option. Ofcouse I would prefer wall to breath.

 

Last question, what treatment I should do before plasterboarding the wall?

 

Thanks

[twice round the block]

Did there used to be a fireplace and chimney in the room that has since been removed?

[Krishna24]

There is chimney. However, no issues around chimney at all. 

[Mike]

18 hours ago, Krishna24 said:

Do you think I should apply any masonry paint on gable end to stop water going through?

I'd use either or a lime render, preferably over external insulation (but stopping short of the DPC, if there is one), or a vapour-permiable masonry paint, or both. I'd strip the existing masonry paint first, though that may not be easy. Try a paint stripper, or get in a specialist to steam it off.

 

18 hours ago, Krishna24 said:

what treatment I should do before plasterboarding the wall?

Internally, nothing - just let it dry out for as long as you can. Then vapour-permiable insulation (if you can't insulate externally) + lime plaster + vapour permeable paint.

[Redbeard]

20 hours ago, Krishna24 said:

Last question, what treatment I should do before plasterboarding the wall?

 

Don't plasterboard it! Lime plaster. 

 

+1 for external wall insulation, though you will have to build a 'gable ladder' to extend the roof line.

 

[Krishna24]

Mike, external wall insulation is out of question for now (too expensive). What kind of vapor permeable masonry paint I should use. Any recommendations of website or brand.

 

Thanks

[Mike]

3 hours ago, Krishna24 said:

What kind of vapor permeable masonry paint I should use. Any recommendations of website or brand.

I don't recall what I last used, but Mapei Silancolor and Emperor would be on my shortlist. By the way, if you do end up painting direct to the wall, remove the point by steam, not paint stripper - you don't want any residue to strip off the new paint.

 

3 hours ago, Krishna24 said:

external wall insulation is out of question for now (too expensive)

I guess there's a small chance that a new grant/subsidy scheme may turn up now there's a new Government. Possibly worth handing on a few months just in case?