DPC question

[JohnSandalo]

I have used Dryzone very successfully to treat rising damp (and it certainly complies with BS6576 as it has BBA and other certifications). Obviously it will only work if the source of your problem is indeed a defective DPC.

Thompson's Waterseal is effective against rain penetration as long as you deal with any faulty pointing or cracks in the masonry. It is stearate-based so will only last a few years as it will get broken down by sunlight. If you want a longer-lasting product you would have to use a silicone-based waterproofer which would cost a bit more.

 

[GJUK]

Thanks again.

Here is where I'm at with this, as I've been a bit busy decorating now that I've finished one room I can turn my attention once more to this living room.

Here is how it looks right now, I've cleared out the area just in front of where the fire would go, it was damp and fill of rough rubble, so I've taken it down the the brick work level.

Pic:

I have bought the following for dealing with the joists.

Once treated I will, as you advised, wrap them with this dpc and seal them up so they can not get wet!

Then, once I've done this I will apply dryzone to this area. All of the red squares is roughtly where i will be applying it. (where the red squares are over the joists in the image, I'm obviously not drilling the joists just at this level in the the brick work for the dryzone)

I will then use a blue dpc sheet, on top of a bid of builders sand and concrete the area I've just removed infront of the fireplace to build up this level.

So. Comments on my plan of action.

(sorry if i seem to be planning this too much and not doing anything, I will get around to it at some point!)

Jon

 

[stanna]

The bit in front of where the fire goes is the hearth. If your not planning to use this again then just run a new joist over it (maybe dig a bit more soil out). Sit this joist on dpc and your sorted no need for concrete.

If i were you i would break out the floor of the fireplace to the same level as the hearth currently is and concrete that after placing your membrane and lapping it up the walls to a level above where the concrete finished height is. Its unlikely there is a membrane under it and damp will get through it.This would allow you too inject your Dryzone at a more consistant level also before concreteing.

Your plan for the dryzone looks along the right lines just imagine your creating a waterproof band between the courses and its obvious where you should inject ie stepping up courses etc.

Your on the right track though.

 

[GJUK]

Nice one mate,

I will do what you suggest and level it out.

Cheers

Jon

 

[Peadee]

GJUK,

I had a damp problem a couple of years ago and I tried the DryZone but it did not work.
Initially I had damp on one wall and this was a single skin internal wall so I thought I was lucky cos this would mean it was localised to that wall alone. I was wrong. it was obvious within a few weeks that the DryZone had not worked and this p!55ed me off no end. I was lucky though cos a month or two later i noticed damp patches elsewhere. Lucky because if the DryZone had worked I would have gone ahead and spent lots of dosh finishing off my house only for the damp to appear elsewhere.
Having looked into the issue of damp it soon became clear that all the chemical treatments available are in no way guaranteed to stop the damp, hence the need for a waterproof render. This will contain the damp should the chemical fail. It has to be rendered up to 1M I think or maybe 1.2M. This is physics, water cannot rise any higher than this due to the gravitational pull on it. I took a more drastic approach to remedy my damp problem. Drastic but guaranteed and, because I want to live here I was prepared to do it. I physically replaced the DPC. This was hard and dirty work but it has worked. I had to remove the whole bottom course of bricks around my living room to achieve this. If I were you, while you are in a mess anyway, I would take this apprach. The materials are cheap enough. My room is 8.5 yards X 4 yards and the DPC and joining tape cost £50. It took a full week of work to do it though, but well worth it for the peace of mind. I have pics if you would like to see how I did it

Peadee