Strip Footing on Crushed Stone
Strip Footing on Crushed Stone
(OP)
I'm designing an attached, 24'x30', two car garage for a friend's daughter pro bono in upstate New York. The house it will be attached to is around 15 years old.
I've done a few other residential designs for one and two story homes (foundation and structure), but luckily, the soils have always had enough sand or other stable materials not to have to worry about being expansive or otherwise complicated. So, 8"x16" (or 10"x20") strip footings placed on undisturbed native soil have been sufficient.
The soils at the site for this garage, however, have a high percentage of clay. To deal with this, I had thought to have 8"x16" concrete strip footings placed on 8" of crushed stone in a 24" wide bed, and backfilled with clean fill to spread the loading over a larger area and prevent potential long term settling into the softer soil.
The elevation of the footings are too deep to take any foundation drains "to daylight".
Am I overthinking this (placing footings on crushed stone) for a simple, one story garage? I wouldn't be so concerned if it was unattached, but I'd hate to see the siding buckle as time goes on where the garage joins the existing house. I also don't want to hire a soils engineer for something that's probably simple and straightforward.
Thanks!
I've done a few other residential designs for one and two story homes (foundation and structure), but luckily, the soils have always had enough sand or other stable materials not to have to worry about being expansive or otherwise complicated. So, 8"x16" (or 10"x20") strip footings placed on undisturbed native soil have been sufficient.
The soils at the site for this garage, however, have a high percentage of clay. To deal with this, I had thought to have 8"x16" concrete strip footings placed on 8" of crushed stone in a 24" wide bed, and backfilled with clean fill to spread the loading over a larger area and prevent potential long term settling into the softer soil.
The elevation of the footings are too deep to take any foundation drains "to daylight".
Am I overthinking this (placing footings on crushed stone) for a simple, one story garage? I wouldn't be so concerned if it was unattached, but I'd hate to see the siding buckle as time goes on where the garage joins the existing house. I also don't want to hire a soils engineer for something that's probably simple and straightforward.
Thanks!
RE: Strip Footing on Crushed Stone
The garage isn't going add much weight at all, so I wouldn't be concerned. If you were putting on a 2 story addition, then I might not be so fast to say okay.
RE: Strip Footing on Crushed Stone
You can place concrete directly onto the gravel bedding, as long as the concrete has a reasonable slump, say max of 6 inches.
RE: Strip Footing on Crushed Stone
RE: Strip Footing on Crushed Stone
RE: Strip Footing on Crushed Stone
RE: Strip Footing on Crushed Stone
RE: Strip Footing on Crushed Stone
I can't take footing drains to daylight, but I could take french drains to daylight (or at least install gutters) to keep water shed from the roof away from the foundation and reduce the likelihood of soil expansion/movement.
RE: Strip Footing on Crushed Stone
RE: Strip Footing on Crushed Stone
RE: Strip Footing on Crushed Stone
RE: Strip Footing on Crushed Stone