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1,180 Damp Proofing questions

Damp problem under bay window

A company cleared a damp problem in 1998 under a bay window. They did not replaster inside. I now have damp patches on the same wall could this be damp in the plaster still or the original problem?

High level garden causing damp

I am purchasing a property, which has a few minor damp issues, one of which is a high garden to the rear which is slabbed. It is currently close to the DPC and causing some damp on the internal wall. Long term I want to fix this properly but can anybody advise on a quick fix. The yard is shared and the slabs will all need to be lifted an relayed in due course, but just want to prevent damp this winter. The ground slopes toward the house but the paving is relatively flat, just uneven.

I was hoping to lift the slabs next to the house, dig a trench along the wall, say 12" wide and 12" deep, relocate the soil and backfill the hole with large gravel, then put the slabs back down, to improve the drainage so water cannot pool close to the DPC/Concrete floor. Would that be beneficial?

I think the next step would be to cut the slabs so they are 6" or so away from the wall. Beyond that I think lowering the garden would be the solution but it would be more expensive, complicated and involve the neighbour/freeholder approving it.

Additional: Chemical damp proof course has been installed very recently and there is also the original slate damp proof course

Can I dot and dab after an injection cream dpc?

Hello, does anyone know if I can dot & dab plasterboard to the wall after fitting a dryzone type injection cream? And if so what is the best way to do it?

Musty smelling soil coming up through floor in Victorian house

We have recently bought a Victorian house. The front room smells very musty so we took out carpet and underneath was a chipboard tongue and groove floor. Smashing some of this up made it pretty evident the smell was coming from under the floor. There is about 8" of free space and then damp soil. No signs of rot and the floor joists (from what we can see look good and fairly new). The air brick isn't blocked but there is only one in that room so we might put in some more, but other than that we are fresh out of ideas.

PLEASE someone help me. I'm desperate to start using that room. I don't think there is a leaking pipe underneath. The front garden does slope down (though well below air brick and dpc) and we are mid terrace so have nowhere for the surface water from the garden to drain to anyway.

Is there anything we can put on top of the soil to stop smell and damp? I don't think we can concrete as pipes run under the floor.

Thanks in advance,


New ext.want patio flush 2 bi-fold but not allow 2 brick drop for DC. NO decking! Way round?

My patio would stretch along the whole rear of the house, all new extension. The DPC is clear to see 2 bricks down. There is a bi-fold door exit and exit from utility. I am happy enough to have a step down from the utility but the whole point of me having bi-folds was to step straight out onto a patio. I really do not want decking and feel there must be a way around having a step. One option that has been suggested is making a "really large step" to go straight out from Bi-folds and then step down to keep the rest of the patio below the damp course. Do you have any suggestions?

Are air bricks required below wooden flooring?

I have discovered the joists under the wooden floorboards in my 1880's house have wet rot and historical woodworm infestation. We pulled up the boards and to my understanding, there should be air bricks on the outside, above the floor level, and then air bricks on the inside, below the floor level, to aid ventilation. There are no air bricks on the inside (just on the outside), the walls are narrow cavities - what is the purpose of having air bricks just on the outside and not flowing inside the house? Should their be air bricks to aid ventilation under the floors? Some of the timber below the main joists are touching the soil, hence probably a contribution also to the wet rot problem, which to my understanding needs to be dug deeper and the joists replaced with treated timber, is this correct?
Thanks in advance for any advice.

Basement/ground floor flat has no damp-proofing

We live in a maisonnette flat - the lower ground (basement) floor is an open plan kitchen/living room/dining room, and the ground floor has a living room, bedroom, bathroom and hallway. We have the bottom two floors of a 4-story detached stone house (not sure of the age - early 1900s I think).

My husband has lived in the flat for 10 years. In the past couple of years we have had an increasing problem with damp, throughout the whole flat but particularly on the bottom floor. We got someone round to look at it recently, and it transpired that there is no damp-proofing or tanking in the flat. This fact was not revealed when my husband had the Homebuyers survey done before he bought the flat.

We have been informed that to deal with the damp problem, we'd need to spend around £17,000 on the tanking/damp-proof course... money which we simply do not have.

We were planning to sell our flat and move on in the next couple of years; our fear now, obviously, is that we will never be able to sell the flat without getting the damp proof course put in.

So my questions are: a) is there any easier/cheaper way of dealing with the damp; b) if we don't get the damp-proof course put in, is there any way on earth anyone would still buy our flat (I realise we'd have to reduce the price to reflect the lack of damp-proofing)?!

It's quite a dire situation we find ourselves in, so any advice greatly appreciated!!

Damp Proof Course under ground level for a couple of years

Looking to buy a property where part of the damp proof course is under ground level by a few centimetres. Chemical damp proofing was done a couple of years ago and it looks like the current owners have simply put paving in that sits a bit high, has gone over the damp course and blocked off the air bricks.

Surveyor isn't overly concerned as the property is 1900 terrace and they suffer a bit from damp (apparently). It also looks like the work is a couple of years old that may have caused this.

Immediate thought is to reestablish the gap by bringing the paving back and ensuring there is adequate space for the bricks to breathe, then let the lot dry out.

Any thoughts on additional work that I should be considering?

Damp proof, replastering and rendering done 4 years ago: now cracks and inside wall black with mould.


4 years ago the previous owners of our 1850's end terrace had work done to the house to erradicate a damp problem. Now 4 years on there are large black circles under the wallpaper coming through. I have looked at the outside of the house and noticed that there are large cracks directly outside where the black mould has appeared. Some builders have had a look for me and said that the rendoring has not been finished off properly, one said it has been done in 2 halves causing the cracks and another has said that because the rendering has been done up to the top of the bedroom ceiling and not up to where the roof is the rain is hitting the wall and sitting on this ridge where the rendering has gone up to causing the cracks, the builder said the company who did it should have tiled this ridge so the rain would flow back down instead of sitting there.

I have spoken to the company who say they have no guarantee and it is our problem but if this is job that has been done to poor standards I will get others involved. We have only been in the house 10 months and this was not picked up by the surveyor. Would anyone be able to give some helpful advice please?

Thank you.

Kitchen plaster flaking / white fluffy powder in areas


Our kitchen has a small extension on the end of it and we have some issues with the plaster work on one wall only. The wall has a washing machine and dishwasher along it (if relevant!).

The plaster near the dishwasher is mostly fine but along the corner edging the plaster has eroded slightly exposing the metal corner bit (if that makes sense!) which has gone slightly rusty. This has happened from about a metre off the ground and extends for perhaps 50cms on and off along the corner edging.

Rather than the kitchen and extension being one large room, the extension is separated from the main kitchen as a part wall (running floor to ceiling) extends into the space from the outside wall. It is on this part wall that juts out and separates the extension/kitchen that the plaster has bubbled and there is a white fluffy powder present. The area affected is perhaps 30cm by 15cm and again seems to affect mostly the corner areas of the plaster.

I have pulled the washing machine out and the plaster behind it seems in good condition and dry. The wooden skirting is also unaffected.

Please can anyone suggest what I can do to remedy the problem? It just seems strange that only certain areas are affected, so I'm wondering if its a condensation problem rather than penetrating damp which requires a damp proof course.

Thank you so much in advance - any help/advice is much appreciated.


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