Need help with adding foundation tile

tc18ny · Oct 20, 2004

My problem is every winter the Northeast corner of my foundation wall (concrete block), cracks slightly in a morter joint and lifts about 1/4''. I know the ground is freezing outside the wall. I think the causes are: mostly clay used for back fill and it is the lowest point in the grade around the perimeter of the house. What I plan on doing is digging all the way down to the footer about 3 feet out from the wall, about 10 feet in each direction from the corner. Dig a trench at a 45 degree angle from the corner of the house to the side yard where it is naturally sloped down and will end in a small ditch which has formed over the years from the culvert at the road. Lay tile up against the house and "t" it into a tile that runs the length of the trench. Cover the whole thing with 4 to 5 feet of stone and the rest with topsoil to re-seed grass.
I can use my neighbor's old case Hoe to do alot of the work. My only problem is getting close to the house with it. The hoe is very old and very jerky, so I can't get as close as I would like. The rest will have to be done with good ole' fashioned elbow grease.
Do you think all this is overkill? Has anyone had a similar problem, and how did you fix it?
-Dave In NY

bczoom · Oct 21, 2004

tc18ny

I had a similar issue (but on a much larger scale) and your resolution seems close to what I did. A couple questions and things to consider.

How wide of a trench were you planning on digging?

I'd try to get right up to the house. What is the siding of the house? Can it be covered with plywood or something to protect from the hoe? If you're going a couple feet wide, can you dig somewhat near the house (staying away enough inches to make sure the hoe doesn't hit the house) then scrape off the block into the trench and clean back out with the hoe.

For the tile, are you going to use 4" sched-40? I'd consider 1 tile a few inches up from the bottom and possibly another up a couple feet.

Now, the big issue! Safety. The bank of that trench will need to be heavily stabilized if you're considering going in. In particular, the trench going out at 45 degrees will generate external corners. You can pretty much plan that do some degree it'll collapse. If at all possible, stay out of the trench! If you need to go in, stabilize the banks first and always have someone above ground with you.

If the hoe can do a pretty decent job of cleaning out the trench, you shouldn't need to go in. After the hoe is done digging, throw about 4-6" of stone in. This next part will take a few people. Pre-assemble all your pipe above ground (don't glue until you've seen if it fits correctly. Once it fits correctly, using a few people and some string, lift the whole thing up and lower into place. Then backfill. When I did mine, I filled with stone to about 1' from the top, pot down some filter cloth then covered with dirt.

Good luck!
Brian

tc18ny · Oct 21, 2004

Thanx for the suggestions. The trench will be 9'' wide so no, I will not be going in it. The siding is T1-11. I'm going to get as close as I can to the foundation wall, then do what you suggest and scrape the block. Hopefully all goes well with minimal manual digging. I better hurry up, winter is almost here! The weather has been nothing but rain here for about two weeks, so it's been tough to work on.
Dave

bczoom · Oct 21, 2004

tc18ny,

How deep is your footer? (Mentally, I was thinking 8' when I wrote my response).
If 3' or less, you can do some shovel clean-up. 4-5', you'll probably want to use someting like a hand post hole digger. Any deeper than 5', I can't think of a hand tool to get down there to clean out the trench.

Brian

tc18ny · Oct 21, 2004

Yep. It's 8ft to the footer. Almost every home around here has a full basement. The trench against the foundation will be about 3ft wide, so wide enough to clean out. It's not going to be one of the more fun projects I have done especially with all this rain. I'm hoping to get the hoe all day saturday, it's supposed to be in the 60s and fairly clear.
Dave

bczoom · Oct 22, 2004

Dave,

You've got me confused now...
2 responses:
The trench will be 9'' wide so no, I will not be going in it.

The trench against the foundation will be about 3ft wide, so wide enough to clean out.

Using the latter, it sounds like it'll big enough to climb in. I can't emphasize enough how dangerous that is unless the banks are supported. Please to as much as you can from above ground.

Junkman · Oct 22, 2004

There is no safe way to dig next to the foundation and only have it 3' wide and work in that trench also. I suggest that you go out about 5 or 6 feet and taper the sides from bottom to top to avoid cave in of the ground. I also don't think that it is reasonable to believe that you can complete this task in one day. Good luck with this project, you sure are going to need it. Stay out of the trench under any condition, you don't want to be burried alive. Trenchs not as deep and much wider have killed people in the past. When the excavator dug the trench for my underground service, it was 5' deep and 10' wide with sloped sides starting at the 10' mark, since we were working on it. At one end, there was a ramp dug to walk down into the trench. This was done by an experiance excavation contractor.

Currmudgeon · Oct 22, 2004

I agree with sloping the sides of the hole. Clay will stand straight up, but then can fail in big blocks with no notice. Sand won't stand long, so the slope is kinda self enforcing.

The discharge trench will be a bit of a problem, if it's eight feet deep. You definitely don't want to go into it unless you have a trench box to work in, or slope the sides back. You can do most of the work from the top, but getting the trench bottom level will be tricky. You can take a bright laser level, strap it to a piece of 2x4, and shim the whole mess to a 2% slope. Then you can use the laser spot on the back of the bucket to get grade.

Assemble the pipe outside the trench and roll it in, the way they do for gas pipelines.

The problem will be, when something goes wrong and it will only take five minutes in the death tra... er, trench to fix it.

This is more than a weekend job for an first timer, no matter what kind of equipment you have. I'd still do it myself. Getting the water away from your footing will be worth it.

While you have the hole open, you can consider waterproofing the outside of the foundation. You may want to go with somehing better than the bitumastic damp proofing they usually apply.

keeney · Oct 22, 2004

With that much rock being dumped into the trench, it seems to me that the drain tile/pipe is somewhat superfluous.

I would think that only the last dozen feet of the trench would need the pipe to collect the water and direct it to some kind of discharge.

- Rick

keeney · Oct 22, 2004

As far as the ditch goes, when my water supply was connected, to dig a 9' deep ditch, they dug it about 5' wide at the bottom. It was close to 20' wide at the top.

- Rick