Cruddy damp proofing or normal drying?

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LondonJoe

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Hi all. I'd like to ask the experts opinions on whether I've got a dodgy case of damproofing or the situation is normal. In a nutshell, I had a damp wall, solid brick with no cavity, with rising damp which I had treated 6 months ago. Damp plaster was hacked off to height of 1m, chemical DPC injected, the wall lined with a damp proofing membrane (sorry, can't remember the brand but I checked it out at the time and it seemed fit for purpose), membrane sealed, plasterboard dot-and-dabbed then plastered over. Jobs a good 'un. Or so it seemed.....

3 months later the paint started to flake in a corner above the repair. This has expanded out into a patch of fuzzy paint and flaking about 1ft square, plus another smaller patch round the corner. There's no obvious sign of salts on the surface but it's noticeable the problem areas are where the previous paint film (standard condensation proof kitchen paint) was torn from the wall during hacking off.

The questions keeping me awake at night are:

Is this a bodged repair job by a cowboy?

Does this indicate the new DPC has failed, or is it just the case of trapped damp above the new DPC having to get out somewhere? The exterior of the wall is covered with a waterproof render and it did occur to me that with nowhere for the water to go lower down, it's simply going to come out higher up.

If the DPC is working, is this trapped water eventually going to dry out so I can just repaint in six months and be done?

Can anything be done on the exterior to speed the drying along? Currently it's rendered down to ground level (bad I know, previous own did it honest!). I've had a suggestion of hacking the external render off up to just above the new DPC and refinishing it it there with a stop bead. Would that give the walls an opportunity to breathe and dry naturally? Or should I just take all the render off for the summer, or look at something like breathable K-rend on the exterior?

Cheers all and thanks for any help you can offer.
 
Firstly a lot believe rising damp is a myth, secondly a metre high is minimum, I always would have gone 1.2 or 1.5 . Seems to be trapped water in the wall but then again you have a membrane inside on the bottom metre. What is causing the damp, is there a gutter or drain that is leaking or broken, a couple of photos of the inside and outside would help. You do seem to have a lot of knowledge yourself.
 
Thanks very much for your input John. I've got a few photos which might explain whats happening here. The first one is the exterior of the wall where I'm having the damp problems:

Cruddy damp proofing or normal drying?


The next four are the damage internally and damage to the render externally pre-repair.

Cruddy damp proofing or normal drying?


Cruddy damp proofing or normal drying?


Cruddy damp proofing or normal drying?


Cruddy damp proofing or normal drying?


To give you an idea of what's going on the in the main exterior picture and possible sources of damp:

1. The white render goes all the way down to ground level.

2. The step in the patio is about 6 inches above the main patio level, and finishes about 2 inches below interior floor level.

3. Water run off by the rendered wall is as follows; to the left of the step it runs away from the wall. On the left half of the step it runs away from the wall and onto the patio where it seeps away into the earth; on the right of the step it flows to the right, off the end of the step and into a sort of run off by the green soil pipe. The next picture shows that are in more detail:

Cruddy damp proofing or normal drying?


The green soil pipe base is surrounded by a cement fillet which slopes away from the building. This flows into a concrete run which extends away from the building about the length of the step, then drops off into clay soil. Previously this run off was filled with gravel and soil with a plant trough on top. I've no cleared this all out, but the clay is very slow to drain water.

I suppose my next questions (apart from is the dampproofing job bodged) are what I can do to help reduce water ingress to the walls.

Obviously the run off to the right side needs to be kept clear of debris so I may fill the gap with large gravel to help channel the water away rather than putting plants back.

I've had a suggestion to hack off the external render up to the above the DPC (that'll be about level with bottom of the patio door hing in the photo) and re-finish with a stop bead. That, I hope, will remove any capillary action up the render and also leave a course of exposed brick to give the wall an alternative route for water egress. Is that reasonable.

Another suggestion was to cut off the last paving flag on the patio step and break that back down to patio level to try to keep water from the step top further away from the walls.

My final thought was that in a worst case scenario none of these things will help and I'll have to install some sort of patio drain. This would be problematic as I don't think I can drain to the clay soil and the nearest actual drain I have is round the corner and slightly elevated, so I'd be talking about excavation.

A final photo here just to add some context. This one is the side return of the house and shows my nearest drain, plus the level of the patio compared to an airbrick.

Cruddy damp proofing or normal drying?


What is the red render around the base of the wall for? Would the original DPC lie behind, beneath or above this?

Thanks very much for your help!
 
im with the dampproofing poster boy, irish, on this one...........rendering to the floor isnt a good sign and if the render is crap, cracked etc its gone allow water in and as you've said it has nowhere to go but through the wall.

wouldnt have thought you would have needed it injected with installing a membrane
 
Was the wall treated with an anti sulphate ?

This is why damp problems should be carried out by "experts"
 
Whatever happened to the beardy one, lucius's mate ? I can't rem his name but he lived in France and could see damp rising everywhere :confused:
 
Thanks for all the responses! I did try to post a reply with pictures yesterday but it doesn't seem to have worked, so I've created a web album with a load of pictures in which you can open in a separate window. The album is here:

Link Removed

The first picture is the exterior of the wall which shows the damp damage. You can see the render down to ground level, and the top of the step is about 2 inches below the internal floor level. The big green pipe on the right is an iron soil pipe which disappears through a concrete fillet into the ground. It's old but it's definitely not leaking above ground. When I pour water on the around the patio area it runs away from the house, apart from the right half of the step where it runs off to the right and into the gulley in front of the green pipe.

The next two pictures are the internal walls pre-repair. The damage rises about 80cm up the wall.

The next two pictures show the external render. There's some cracking obvious at the bottom of one picture, and the other shows some bubbling on the render. Incidentally does anyone know what the red render band around the base of the house in that photo is? It seems to be on all the properties round here and I can't work out where the original DPC is in relation to it.

The next couple of pictures are the soil pipe and the water run off by the step. This was all filled with mud and gravel until recently but it's now cleared out. It leads out to clay soil which drains slowly.

The pictures after this are of the step and it's height relative to the surroundings, and the final picture is around the side of the house looking towards the patio and shows my nearest drain. Again, it seems to be in good nick, there's water in the trap at the bottom of the drain and no obvious leaks.

Hopefully the pictures might be able to give you a better idea of what might have been the cause of the original damp and whether the repair was adequate or not. Thanks again everyone!
 
Why did they leave the external rendering on in the first place? Surely that would have to be hacked off or at least grinded to a new level above dpc
 
Thanks for all the replies. I've posted a couple of long replies with photos and more information but they're not appearing, apparently they need to be approved by a moderator. I'lll try to chase it up'
 
Ok lets see if this works. You may have to cut an paste the link into a browser as I don't think it'll let me link it.

Link Removed
 
To me for a start you need to do something with that step, its going to bridge the DPC for a start. also you might be getting water coming in under the door so getting rid of that step would help.

Looks to me you need to hack of the outside and repair that, also you need to get that down pipe sorted everything needs to fall away from the property.

To behonest with you the penertrating damp is probably the main problem, you will be lucky to get them back.
 
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