Fitting a DPM

[James Varty]

I'm considering fitting this myself in my garage and covering with a screed - floor is currently damp and uneven. Any suggestions as to a good place to buy a DPM / jointing tape, etc?

Cheers

James

[Set Square]

If you already have a solid surface, you can get some bitumen-type liquid which you simply paint on, and then screed over. That may be easier than laying/joining sheet material. The paint-on variety was used when part of my garage was converted into a utility room - and it seems perfectly ok 16 years later.

[Merryterry]

which you simply paint on, and then screed over. That may be easier than laying/joining sheet material. The paint-on variety was used when part of my garage was converted into a utility room - and it seems perfectly ok 16 years later.

-- Cheers,

Trouble with bitumen type liquid is they seal the damp in the brickwork and the pointing will degrade. Consider injecting a proprietory chemical DPC into the brickwork. The injecting kit can be hired from Hire Shops and they will also sell you the chemicals.

It is dead easy to do.

Good luck

Merryterry

[meow2222]

Assuming I've understood right that you want to dpm a concrete floor, not walls, I'd just use a waterproofer. Have done that twice now, good results each time. Concrete is quite happy staying wet. One that soaks in and is clear will look much nicer than bitumen.

This is not a good approach to use with brick walls though.

NT

[Set Square]

But he wants to screed over it, to get a level surface - so it won't show, anyway.

[meow2222]

ah ya :)

NT

[Rick Hughes]

Rolls of DPM are cheap in any builders merchants. ... you don't need tape , just overlap by at least 300mm. a couple of strips of gaffer tape will help hold things in place while you lat the screed. Do you have a DPC in the garage walls ? if so make sure that the DPM laps up the edges and you don't end up with the edge of the screed touching brickwork that is below to DPC.

Ideally DPM and DPC should be on the same level, and then screed is laid above the DPC level, but not imperative if you have DPM lapped up sides of screed.

How are you going to treat the garage entrance ... remember that the edge of a screed will not take car traffic.

Rick

[James Varty]

I'm quite sure that there isn't a DPC in the walls. I'm planning to put the DPM up the walls as well (not totally sure how yet, but at least 1 metre up before I drywall the garage). I thought tanking the garage using a physical DPM would be the best way of ensuring the damp is kept at bay. The walls are only one brick thick and not rendered on the outside on two sides, which I think is why its getting damp. Once I've got the garage in a fairly dry state I'm going to build a small drum practice booth in there using plasterboard on a 2 x 4 frame.

The 2 options I'm considering are a physical DPM or doing a few coats of bitumen half way up all walls and the floor. Not totally sure which way would the cheapest, easiest or most effective!