Is This Penetrating Damp? What Would You Do?

[grumpyM0le]

Hi,

I'm an inexperienced first time buyer. November moved in to the house to find damp plaster on 1st floor bedroom wall (external).

Based on the description below and attached pics, what might be likely causes of the damp, and what repairs should I realistically expect? Are there any specific questions I should ask when getting quotes?

There's a boiler mounted to the wall with a flue passing through to the outside. Damp appears around the flue and the plaster behind the boiler is crumbling. The damp spans the entire length of the wall, just above the skirting, but rising in places.

The external wall is fully rendered with a 2-3 cm thick layer that is cracked in places.

 

[HERTS P&D]

Welcome to the madhouse! Congratulations on your property purchase!

What did the survey say?

Is there a tank in the loft? I can see an overflow sticking out the wall.

Andy

 

[grumpyM0le]

Survey didn't mention anything unfortunately - the house was surveyed in late summer when the weather was warm and dry. There's no tank in the loft, looks like there was one, but it's been removed.

 

[HERTS P&D]

Didn't the survey mentions the cracks in the exterior wall?

Andy

 

[grumpyM0le]

Yup, there was a sentence recommending filling any cracks in the render to avoid potential water ingress. With that in mind, we're getting quotes for that now, but because I don't have much experience, I'm looking for advice from anyone with a bit of knowledge.

If it is a case of repairing / re-rendering, what do you think would be the best way to tackle the damp wall afterwards? Would you recommend doing anything else to seal the flue join?

 

[tell80]

No matter the season or the weather the surveyor must have seen the blown render on the gable wall and the water damaged plaster on the bedroom wall.
Have you examined the conditions of the rooms below the bedroom?
With surveyor's binoculars the condition of the verges could also have been clearly seen?

The gable render needs removing and new sand & lime render installed.
Go into the loft & examine the gable triangle - & the roof area below the verge.
The bedroom plaster needs hacking off back to masonry, and also rendered with sand & lime and, say a Limelite Remedial finish.

 

[grumpyM0le]

Thanks for the the advice, will go check out the gable.

From your suggestions, plus the previous, it looks like the course of action is: re-render wall, re-point wet verge and re-plaster interior wall.

The survey did mention "minor hairline cracking" to the wet verge and recommended repointing these in addition to filling cracks in the render. So there was warning that this was coming, which everyone here seems to have picked up on!

The surveyor did downplay these issues and he missed signs of damp inside the house though. In hindsight that gave me a false sense of security, but guess this is a case of buyer beware.

Thanks again for the help, I'll start getting quotes in for the works.

 

[opps]

No matter the season or the weather the surveyor must have seen the blown render on the gable wall and the water damaged plaster on the bedroom wall.
Have you examined the conditions of the rooms below the bedroom?
With surveyor's binoculars the condition of the verges could also have been clearly seen?

The gable render needs removing and new sand & lime render installed.
Go into the loft & examine the gable triangle - & the roof area below the verge.
The bedroom plaster needs hacking off back to masonry, and also rendered with sand & lime and, say a Limelite Remedial finish.

Why a lime based finish?

If the OP goes down that path wont they need to repaint all areas with "breathable" paints, i.e. not regular emulsions and masonry paints.

 

[stevethespreader]

Is the wall cavity or solid?