Converting my garage. What am I doing??!!

3 Nov 2013
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United Kingdom
Hello all - this is my first post so apologies if I break and forum rules or ask any stupid questions!

I am converting a single skin block work garage into an insulated room but there is evidence of damp on the walls - salts and wet to the touch in bad whether.

There is already a plastic DPC above the first course and I have seen water pooling on the DPC itself where it protrudes a few mil from the brick work.

My intention was to tank the inside of the wall with ka tanking slurry a meter or so from the floor.

My question is, should i tank all the way to the floor or stop at the DPC? I am concerned that if i bridge it with the tanking solution this will make the problem even worse!
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I would not bother with a render, use a bituminous brush applied membrane such as RIW. Paint it down to the floor. When you stick a dpm down on top of your existing slab, lap it up the walls a bit and tape it to the RIW.
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Thanks Fred. I already started with the tanking though - I couldn't wait to get started! It might be overkill but I enjoy the work so I don't mind. I have stopped at the DPC and left it bare on the bottom course to the floor. I will then tape the DPM to the wall above the DPC as advised by your good self. Fingers crossed....
Just as an update, I tanked down as far as the DPC with two coats of KT Tanking Slutty but was still getting white marks and patches on top of the slurry.

I decided to bridge the DPC with the slurry so the tanking now goes all the way to the floor and about three inches on to the floor aswell and a week later with rain most days, still no sign of water ingress so it looks like this was the right decision!

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