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Damp Proofing Questions

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707 Questions: Damp Proofing


Damp caused by bathroom leak

Hi there - we recently found damn in our new home (1930s terrace conversion) and we've had someone out to look at the cause. They've said that they can't spot anything sinister (no dry rot, no rising damp) and that there's no signs of leaks in the plumbing itself.

They've suggested that the cause has been something as basic as the splashguard on the bath not forming a tight seal with the bath and the tiling in the bathroom being done poorly enough for water dribbling down the side of the bath to penetrate into the floor boards which have also resulted in a joist that extends into the bedroom getting soaked.

The advice I've received so far is to uninstall the bath tub and allow everything to air out for at least a week - then treat any timber that is salvageable but definitely replace the joist which is structurally unsound. This would then be followed by replacing the rotted floorboards in the bedroom and re-doing the bathroom.

What type of workman should I be looking for as it sounds like a mixture of plumbing and carpentry and what would be a fair price for the work?


Ytobeconfirmed 9th Oct, 2012 Damp Proofing
1 Answer u1

Damp problem ??

I'm looking for some information as I believe my landlord is in denial that he has a problem. We have lived in a lower ground floor flat for 3 months within this time my chest of draws and bed have been destroyed by damp/mould. My chest of draws was covered on the back and on the inner part and the draws collapsed due to the dampness. My bed that has a pull out draw was covered in green/black/yellow mould on the underneath of the draw and also on the wood frame in the inside of the bed. My walk in cupboard also has been attached with the mould with me having to fling out a lot of stuff.

He has put it down to the people that came in to clean the carpets before we moved in as the floorboards are wet at the top but not underneath but the rubble under the floor boards is dampish, but the cupboard was not washed so does not explain the mould in there. The wall also has mould damp and wallpaper is peeling.

I need some help to know if there is a bigger problem than he is making it out to be.


Yjdasuk 20th Sep, 2012 Damp Proofing
1 Answer u1

damp musty smell in extension

Hi there
I have a problem with a damp smell in my ground floor extension, its been there for several years and im only dealing with it now as my daughter wants it for her bedroom now. it started a couple of months after i laid a new carpet on it, only weeks after extension was built. there has never been any visual signs in the room of any damp problems but the carpet is very musty and gets stronger when i put my nose right down to it, so it seems as if its coming from the floor. The floor if i remember was laid with breeze blocks then the normal wood chip style floor which goes on top of most modern built homes. extension was pile driven as the original house was when built ten years before. I dont know if that is an issue or not. Some parts of the extension at the bottom are a bit below the ground so the gray foundation bricks are not visible all the way round , also dont know if that is an issue.
Please help with any advise you can.

Yjaysee70 16th Sep, 2012 Damp Proofing
1 Answer u1


We are renovating an old victorian house, and have noticed damp problems. There was a large amount of ruble in the cavity which we are clearing.
There is a large amount of render around the lower half of the house.
Our render goes from the ground to almost 3 bricks above the dpc.
Parts of the render are flaking so we are removing all render.
Question is was that render too high, and should we bother re-rendering ?

Ynatasha_50 8th Sep, 2012 Damp Proofing
1 Answer u1

Damp on Chimney Breast

We live in the upper flat of an 1899 sandstone building. The attic was converted prior to us moving in, but there was always slight damp issue on one of the gables behind diy fitted wardrobes (with no back). We assumed the lack of ventilation on an cold outside chimney wall etc to be the cause of the damp. A year ago we removed the wardrobes. plastered the gable, decorated etc. A mark continued to come through as we were painting so used damp proof paint and [too many] coats of normal paint. The damp has continued to get worse and spread over the course of the year rather than dry out. Despite numerous builders, roofers and a surveyor, the root of the problem has not been determined. There is no mould growth on the wall, the paint has started to crack as we've been running a dehumidifier 24/7 for the past 2 weeks, but the damp seems to vary day to day. We have now removed as much of the paint as possible over the damp area to see whether that helps dry out the plaster (with the thought that damp could be trapped behind too many layers of paint). The paint pretty much came off like wallpaper!! It is my young daughter's bedroom and we are desperate to get a diagnosis. I have read about hygroscopic salt contamination, but none of the tradesmen viewing the damp have mentioned this. Any ideas?

Yclang99 8th Sep, 2012 Damp Proofing
1 Answer u1

Damp proofing concrete garage floor

Hello, I have a garage with an old concrete floor in it. I painted it with garage paint about two years ago, but damp is coming through and forming little white crystals at some spots. All I want to do with it is damp proof it, so not put a complete floor on top of it. I was thinking of putting a layer of DPM paint on it, would that do the job? And would it last when I wlk on it??

Thanks for any help,


Ygoossens 4th Sep, 2012 Damp Proofing
1 Answer u1

woodworm in floating floor

I think I have found woodworm in a sealed oak floor, laid over concrete. Can this be treated or will I need to rip up the floor?

Ywoosloo 17th Aug, 2012 Damp Proofing
1 Answer u1

Damp proof work central records office?

is there a County or Central Records office for all damp proof work carried out even if no certificate given?

Ymaddeline 3rd Aug, 2012 Damp Proofing
1 Answer u1

Damp spots on walls and corner window

We recently bought a ground floor flat in a purpose built block, which I believe was built in the 1970's. One of the walls has the communal bin shed on the other side, whilst another acts a corridor wall. I have recently noticed that mould spots are begining to appear on these two walls. On recommendation in our homebuyers survey due to excessive condensation our windows have been replaced.

When home the windows are opened in order for the flat to ventilate and the extracter fan is on when cooking.

Another issue is that in the main bedroom we have a bay window, in the top corner of the frame (which acts as an external wall) there is a strip of mould appearing, but only in that corner. We have also been getting mould spots on the back of furniture. Is this related?

On contacting the management committee that have blamed poor ventilation, without any willingness to investigate.

Any ideas or solutions that can resolve this.

Many thanks

Ydimples2403 1st Aug, 2012 Damp Proofing
1 Answer u1

damp in groundfloor bedroom

I can't identify the specific kind of damp: the carpet and the sides of the bed smell very musty (and the carpet is discoloured), but don't feel wet, only damp. There's no visible sign of damp (no black mould or anything). It's a bungalow and there are no air bricks, although I always leave a small wndow open day and night in the bedroom. Last year I had the bottom few rows of bricks pointed. I notice there is cement covering where the DPC runs. My query is, which is more likely to be causing the dampness: lack of ventilation, or bridging of the DPC?

Thanks, Joseph at Trident Damp. (This is the only place I can see here to respond to your reply).... The floors are concrete, not wooden.... But it's helpful to know that bungalows are prone to ventilation problems. I think I'll go for the airbrick route and hope for the best!

Ygrannieg 24th Jul, 2012 Damp Proofing
1 Answer u1
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