digging up a bit of the foundation for waterproofing..

[Bubba Gump]

Gentlemen,

If I may offer a small bit of advice. While it doesn't necessarily address the repair itself, I have seen similar issues. Once you do find a suitable method of repair and you've excavated the outer perimiter, I would suggest backfilling with clay and only adding a couple inches of topsoil for grass. The combination of repair and a 8-12" clay cap should ensure you never have another problem. Just be sure to hand tamp (every 2-3") and not use a plate tamper or jumping jack as it could damage both your repair and the foundation.

Best of luck!

[Egon]

Just a thought, have you inquired how much it would be for a guy with a mini excavator to come in and dig it for you? You could then do the sealing work yourself, and even fill it in yourself (remember to tamp it), and you'd probably still be ahead in the money dept. That's just a lot of digging for you, and the fact that the machine could come in and just have it done in 15 min, why, that would probably be worth the money, right? You could have the job done in a day then, and have the next day free to do other things (as opposed to lying on the couch the entire next day, recuperating your back)
ETA

depending on your experience level, I know our local rental will just rent you a mini, if you know how to use it.

Very sound advice.


Also remember the spill pile will add weight to the area just to the side of the trench. Check out the regulations for shoring. You should be able to do it yourself. [ It's been 45 years since I worked with trenches so things will have changed]

Note: do not go by the age old adage you can inspect it and determine if it will not cave in!

Consider sandblasting the concrete foundation before appling the fix.

[ArtMulder]

If you do dig your big trench, make sure you brace it as you go. Too many guys have died when the trench they're digging caves in on them.

Everyone... listen to Ryan, he speaks truth. Our ground here is wet sticky clay under about 10-12" of top soil. Solid. Very. I was sure it wouldn't go anywhere. But this morning I was about 10" from the footings, so about 5-and-a-half foot in the ground with my trench, and I saw a crack start up in the clay wall. I got out in a big hurry, and about 1-2 minutes later watched the wall slowwwwwly cave in. Cost us probably another 2 hrs of work, and good big scare.

Not sure if I'll ever consider tackling a job like this again. Thankfully we're done now.

If it were me, and the crack caused minimal problems inside I would do what I suggested earlier and break open the slab on the inside and put in a small pc of planton (variation of the pic I posted). It would only take you 2-4 hrs.

Scott, I should have answered you back when you posted... My only complaint with a solution like you give is that it doesn't work in an unfinished basement like I have. I have a bare concrete wall there, and no real plans to cover it up. It's just a playroom, and we're leaving it as such. I wouldn't want that bare plastic just sitting out there.

...
...


We followed the recommended method of dig, clean, Aquatec emulsion primer, blueskin WP200, then Platon, and then added about a foot of 3/4" crushed gravel in the bottom of the trench, covered that with weed block fabric, and refilled the hole. I really hop that does the trick.
(That's belt AND suspenders AND another belt. Those darn pants better stay up now!! )

1- getting started digging on Friday
IMG_1407.jpg

2- Friday evening, stopped about halfway down
DSC_2879.jpg

3- Saturday morning, partial collapse of the side wall
1-collapse.jpg

4- Priming with the Blueskin primer
2-primer-emulsion.jpg

5- Rolling out the Blueskin
6-blueskin4.jpg

6- Here's the platon in place, and some (or all, I forget) of the gravel in place. I tell you that electrical service with the big loop-de-loop in the wire was a literal pain in the neck to work around. Ugh.
9-platon2.jpg

7- Lost count of the number of wheelbarrow loads we dumped. One thing is for sure, we need a better wheelbarrow!
IMG_1445.jpg

8- Here you go. Found this can of sprite at the bottom of the trench. The bottom. It is from 1984, when the house was built. It was NOT crushed, and it is still easily legible. 280ml, which is smaller than the 355 cans we get nowadays.
IMG_1430.jpg

[ArtMulder]

ps: In case anyone wants to see how the pros do it, I found this video online that pretty slickly demonstrates a pro job from start to finish.

Note, this is basically an advertisement for a company, and I have no idea if they are a good, bad, or meh sort of company.

http://www.youtube.com/watch?v=dDla-8NCJWo

[Egon]

Thank goodness there were no injuries.


Some clays will stand for a little time and all looks good. Then there is " whump " and a side caves in!

[WillBon]

Hey Art,
I'm looking to do a similar project in London as well. Do you have any left over dimple mat I could buy from you?

[ArtMulder]

Hey Art,
I'm looking to do a similar project in London as well. Do you have any left over dimple mat I could buy from you?

Nope, sorry. Sold it on Kijiji as soon as I could -- someone bought the dimple and the blueskin.