Water ingress through wall

The back of my garage lets water through like it was the biblical flood. The problem is that its 7 foot high and 4 meters wide and the idiots who build the garage did not put a damp course between the garage wall and the 7 foot of soil behind it. Digging the soil out is a nono as there is to much, I have painted weatherseal on the wall however water still gets through. Any advice on how to cure this would be appreciated, the top of the wall is rendered and this does not let water through so would it be a good idea to render the wall with a high amount of cement to make it rock solid? The rare of the wall is not even a retaining wall as the blocks have been built on their sides not flat.

I think a wall should breadth, otherwise it would be VERY damp inside. Off course, if you put soil against it, you should make it watertight. I think the only recourse would be removing the soil, waterproofing the wall on the outside and putting it back (good luck)

If you do it on the inside, the walls would soak up the water and that sucks.

Dig down and use gravel to drain below the damp course.

That just the problem - there is no damp course, and the digging would take forever. I can't get a digger into the area which would need to be dug so I was thinking that I could have a wall built inside the garage so there is a cavity between and make a water drain between the 2 walls.

Can you say mold? Double wall like that is asking for it.

Dig a small ditch from around the back to the front. Small ditch doesn't need a ditchwitch. Install french drains. Recover ditch with dirt.

Will take a shovel and a half a day, but it'll work.

Oh yeah I did not think abiut the mold...Your right and may have just saved me time and money so thanks for that. Im not sure about doing all the digging in half a day, I woulld have to put in at least 1 ditch about 7 foot down, when you think the wall of the garage is about 4 meters long I would be at it for days. I also forgot to mention that there is an 8 foot wall coming from the side of the garage so I would not be able to put in the frence drain to flow off anywhere.

This post has been edited by Siris10: Aug 17 2008, 08:01 PM

We didn't put ours in at the bottom of the wall, we installed them on ground level around the wall. You only have to dig down about a foot and a half. And it made an amazing difference. Used to have runoff running right through my basement. Went so far as to put the washer and drier up on cement blocks so they wouldn't get wet every time it rained. Installed the french drains like I said above and could not believe the difference. Was absolutely wonderful.

This post has been edited by Coyote: Aug 17 2008, 08:37 PM

French drain is a great idea short of redoing the foundation, a french drain will at least lessen it

If I’m reading your description correctly, the wall sounds like a retaining wall or very similar in design



If this is the case then I think it’s more than a simple matter of missing DPC – because if there’s no natural path for the water to drain from the bulk that it’s retaining, then it will need a drain of sorts attaching it instead



There’s some more info on drainage for retaining walls Here

In fact that actual site itself, has a wealth of resources and info that might assist you as well

Yep that would absolutely be the best thing in this situation.

Wiki Link

Well thanks very much for your help everyone...Im gonna go with the French Drain. I am renting a rotovator for the ground in a couple of weeks so this will make it a bit easier for me to dig the soil/clay out.... Hope it works....

rotovators are shit for clay or if the ground is hard they will just bounce along the top.... they are really for breaking up plowed ground prior to seeding..... if you can't get a mini digger in buy a good Spear and Jackson spade

Agree... I have a small one that works great once you get it in the soil, but the jumping when you first start is annoying

My buddy George had the exact same problem in his shop. He solved it by applying a concrete waterproofing product with a brush. This stuff looks like concrete powder but I think it contains silicone. Anyway, you just add water and brush it on. It has totally solved his leakage problem. I can always photograph the label on the tub if you want to give it a try. May or may not be available in the UK and there is a suspicious lack of info on the label regarding ingredients.

That seems to be the solution, im not sure if this is the same kind of stuff:
Concentrate concrete waterproofing, repair and protection

XYPEX CONCENTRATE
Xypex Concentrate is the most chemically active of the Xypex waterproofing products. When mixed with water, this light grey powder is applied as a slurry coat to above-grade or below-grade concrete either as a single coat or as the first of a two-coat application. It is also mixed in Dry-Pac form for sealing strips at construction joints, or for the repairing of cracks, faulty construction joints and honeycombs.
Data Sheet » M.S.D.S. »
Modified concrete waterproofing, repair and protection

XYPEX MODIFIED
Xypex Modified can be applied as a second coat to reinforce Xypex Concentrate or by itself to damp-proof the exterior of foundation walls. Applied as a second coat over Concentrate, Modified produces a harder finish and speeds the curing of the Concentrate. Where damp-proofing is required, a single coat of Modified may be used as an alternative to a spray/tar

I will look into this as im not bothered if the wall collapses in the future as hopefuolly we will have moved by then.

I like tha name Spear and Jackson however i don't think I will purchase one of their spades cos I really don't want to have a whole weekend of digging....cheers for the advice of the rotovator - if they are no good on clay imgonna have to see if the hire company can lift a mini digger about 8 foot in the air to get it where i want it.

Yep, that sounds like the exact same stuff, Siris10. Give it a go. Got to be the easiest solution.
His went from 'A River Runs Through It' to just a hint of condensation from the temperature difference between outside underground wall and inside air.

Those solutions are excellent temporary fixes, if you rent the property it might be a better idea. If it's your house, I'd skip it and sort the french drain out, as it'll just keep coming back.