Waterproofing garage walls again!!!

[RichD1]

I have to replace my insulated floor in the garage because of water ingress through the concrete block walls at the floor level. Originally I just floated chipboard over 50mm jablite. This time I'm going to put down a DPM then some floor joists and then put PIR or grade 70 poly down between and then top with 22mm T&G flooring chipboard.

My question is how to seal the concrete block wall at ground level?

The wall in question is about 400mm from my neighbours concrete block wall and my slab which is also the garage floor goes right up to his wall, so water can lie there but it does dry out. The water doesn't appear to rise up the wall now that I've exposed the inner surfaces to see what's happening and has got wet and then dried since I removed the old floor.

I've looked at Cementone products, both Tanking and Aquaprufe are well regarded, plus there waterproof rapid setting mortar if I need to fill any holes or cracks. But should I just do the inside surfaces so to allow the outside to breath and dry, or should I do both sides?

 

[=Adam=]

If you can access the exterior walls then it is best practice to waterproof both faces. If it is not possible (e.g a basement) then simply waterproof the inside with whatever method you choose. My main concern with any retrofit of internal tanking is that water still penetrates and needs to be removed from the interior in order to prevent mold. The removal of the water is typically done through the installation of a perimeter drain (similar to a French drain) which can then be piped outside.

 

[blackrodd]

I've come upon this problem before.
If you build straight on the floor slab, capillary action will draw the moisture in.
Best practice would be to set a 4x2, on it's flat, set where the walls are to go and using the top as a screed or tamper level. It gives a 2" rebate, stopping the capillary action, with a dpc, where as a dpc on the slab will not!
The guys who erect concrete garages have this problem and offer a cement fillet, I guess about 2"x 2"which, I'm told works.
Prime the "strip" to be laid with unibond and cement and water, a nice slurry, (like a good custard)!and press the cement fillet firmly into place.
You should be able to relay the wood floor, but always on good quality visqueen, laid on the floor and partly up the wall.
HTH Regards Rodders

 

[RichD1]

Yes, the access to the outside wall is reasonable and all above ground level, so the recommendation is to apply the tanking to the slab/wall joint as well as doing the internal wall/floor?

Any recommendation as to which product to use? I was thinking that the Tanking slurry will be better on the outside as it will blend in with the surrounding concrete. Aquaprufe on the inside as it will be covered by the DPM and floor.

I'm also thinking that I could lay some concrete slabs in this area between the garage wall and my neighbours wall with the slabs being raised to tip the water away from my wall and also with a front to back fall to take the water away.

Richard

 

[RichD1]

Any more opinions on waterproofers.

Richard