Foundation Backfill Dirt

[lzicc]

What is a good dirt to use to backfill a foundation? The foundation which is concrete block will be undergrade about 5'. I was going to backfill with shale fill.

 

[tlmartin84]

Give me some more information, size of block, 8" or 12"? Do you have any reinforcement in the block?

Are you placing drains around the foundations??

 

[darkk]

Mine is just regular sifted fill (likefine sand) with the top soil over the last foot or so. My foundation was for the garage 54" deep with a slab center.

 

[wnstwolf]

If you can place drain pipe all around the permiter with abot 12" of crushed stone and somehow have the pipe drain to daylight it will go a long way to keep water out from under the slab. Cover with landscape fabric and stay away from big rocks due to pockets and the like but since it is not insulated or worrying about damage to waterproofing the spoils you dug out should be able to go back in. Big thing is to use something that will pack well and not cause voids but barring bringing in new fill if what you dug out is not full of roots and the like push it back in!

 

[wnstwolf]

PS if your going to add gutters and down pipes now is a great time to bury some added pipe and get the water away from your new facility..

 

[brownbagg]

sand

 

[Kevin54]

What is a good dirt to use to backfill a foundation? The foundation which is concrete block will be undergrade about 5'. I was going to backfill with shale fill.

It all depends on location. Location of where you live, location of the foundation in relationship to the rest of the property, and location as to whether you get a lot of rainfall or very little. Ohio dirt is drastically different from Arizona dirt. Fill in a little more info for a better answer.

 

[lzicc]

I'm in PA. The foundation is 8" block with every 5th foot' of the cavity filled with concrete and rebar. Building is 26' x 40'. French drain is in with gravel on top. Blocks have foundation coating on them, then wrap with Grace TriFlex. I'm just gettin ready to backfill and thought shale might be the best way to go. The other options are clay which I wouldn't think would work good for around foundations or rough topsoil. Once I get the foundation filled in so high, I am going to run drain pipe for the gutters, then finish backfilling. My concern is the best thing to keep it damp/water proof. I am also going to grade around the garage so when the rain hits the ground, it flows away from the building.

 

[tlmartin84]

The clay or shale will work fine with your setup. Im in WV, I have clay around mine. Clay actually seals up almost impervious on top if compacted right. Shale actually at one time was clay, and they share a lot of similar properties especially if the shale is left exposed to mother nature for any length of time.

 

[tlmartin84]

i would also reccomend using 4" PVC (SDR 35, or sewer pipe) for your downspout drains rather than ADS. Its not much more expensive, but it is harder to work with and route though. It does however allow you run a snake through it without punching through the side of it in the event of a clog...

 

[pop pop]

Clay works fine. Most of the south only has clay!

 

[70redbee]

If everyone would put their location in their profile, it would be easier to help.

 

[Kevin54]

I would backfill with shale, put a fabric over that to prevent dirt from washing down in, then finish up with topsoil.

 

[lzicc]

Is landscape fabric the same as the fabric they sale made for drain tile?

 

[rwreuter]

SAND.....only use SAND.....did i say SAND?

 

[mebedave]

3/4" washed gravel. I would backfill the whole the whole trench with washed rock except last one foot, use fabric over rock and final fill with sandy soil. clay will expand and push your block walls in. Be sure to tar your walls and install drain and before tar can dry hang a 6 mil plastic into the tar, this will protect your water proofing. Sand would be my 2nd chose.

 

[K'ledgeBldr]

What is a good dirt to use to backfill a foundation? The foundation which is concrete block will be undergrade about 5'. I was going to backfill with shale fill.

Why wouldn't you just use the soil that was excavated when the foundation was put in?
Having to truck in soil (of any kind) is a major expense that can be avoided with forethought of the placement, and elevation of said structure.
Granted, I realize that is not always 100% possible. Even so, you should have minimal need for additional soil.

 

[64dragnwagon]

I used a shale clay soil for fill in my pole building then 3/4" washed gravel about 2" thick. Pack the fill every 6"