Backfilling is the part of a build nobody photographs and everybody notices five years later. Done right, the ground around your shop or foundation stays where you put it. Done wrong, you get a trench line that sinks every spring and pulls water toward the wall you were trying to protect.
What we backfill
- Around new shop and pole barn foundations
- Foundation walls and footings after the concrete crew is done
- Utility and water line trenches once the line passes inspection
- Old septic tanks, cisterns and stock tanks after decommissioning
- Pool removals and other voids left behind by something taken out
- Low spots and settled areas on established property
Why backfill settles, and how we stop it
The mistake is dumping the pile back in the hole in one go. Loose soil holds air, and over a winter or two that air works out and the ground drops. On a trench next to a foundation, that drop becomes a channel that routes snowmelt straight down the wall.
We place backfill in lifts — six to twelve inches at a time depending on the material — and compact each one before the next goes in. It takes longer than pushing the pile back in, and it is the difference between ground that holds and ground that drops. We also keep organic material out of structural backfill. Topsoil and sod belong on top of the finish grade, not against a footing, because they rot and leave voids behind.
The last thing we do is set the finish grade sloping away from the structure. A few inches of fall in the first ten feet moves an enormous amount of water away from where it can hurt you.
What it costs
Backfill is usually one of the cheaper lines on an excavation job, because the material is already sitting on your property. There is no rock to buy and no trucking to pay for. Price comes down to volume, access, and how much compaction the job calls for.
If the spoil from your dig has already gone and fill needs to come back in, that material gets delivered by a supplier and we place and compact it.
Related work
Backfill often comes packaged with shop and pad grading or follows trenching and utility installs. If water is already finding its way somewhere it should not, look at drainage and French drains instead.
Where we work
Spokane, Spokane Valley, Liberty Lake, Mead, Colbert, Chattaroy, Deer Park, Nine Mile Falls, Cheney, Airway Heights and Medical Lake — about 50 miles out from Spokane. We work the Washington side of the state line.
Grizzly Excavation Services LLC — Washington contractor license GRIZZES767J5. Licensed, bonded and insured. Free estimates.