backyard office footing in soggy soil

[Pirate_Anji]

I'm planning an 8x12 shed/office build in my backyard here in Utah. The site drops about 18" corner to corner, and the ground stays soggy in the spring from snow melt and runoff. I want to avoid pouring a slab since I'd rather not add more impervious surface and make drainage worse.

My current thought is a gravel pad boxed in with 4x4s, extending it past the shed footprint to help with infiltration. But I'm not sure if that's really the best option on a slope. Has anyone here in Utah (or similar climate) done a small shed or insulated office on a sloped, wet site? What kind of foundation worked for you?

 

[mym1nih0me]

hi @Pirate_Anji a sloped site actually gives you an advantage for drainage. You can use a combination of French drains and the slope to your benefit.
Digging a trench upslope from your shed and filling it with gravel and a perforated pipe will collect and redirect the runoff away from your building.
This, combined with a properly leveled foundation, will help keep the area under your shed from turning into a swamp.

 

[shivpagnepapi]

I'm planning an 8x12 shed/office build in my backyard here in Utah. The site drops about 18" corner to corner, and the ground stays soggy in the spring from snow melt and runoff. I want to avoid pouring a slab since I'd rather not add more impervious surface and make drainage worse.

My current thought is a gravel pad boxed in with 4x4s, extending it past the shed footprint to help with infiltration. But I'm not sure if that's really the best option on a slope. Has anyone here in Utah (or similar climate) done a small shed or insulated office on a sloped, wet site? What kind of foundation worked for you?

To keep water away from your shed, angle the gravel pad a bit so water flows away. A French drain or pipe system can also help move water. If your shed's up high, use vented skirting to stop dampness. And if it's an office, insulate the floor, cold air gets in from below.

 

[Nutzy.dad]

Gravel pad can work if you make sure it's well drained and slightly stepped to follow the slope or... deck style foundations on piers or blocks to keep the structure off soggy ground and allow water to pass underneath

 

[Leydsdorppp]

hi @Pirate_Anji a sloped site actually gives you an advantage for drainage. You can use a combination of French drains and the slope to your benefit.
Digging a trench upslope from your shed and filling it with gravel and a perforated pipe will collect and redirect the runoff away from your building.
This, combined with a properly leveled foundation, will help keep the area under your shed from turning into a swamp.

Thanks for this! I'm building a small off-grid cabin on a hillside, and I was worried the slope would be a problem. Didn't realize it could actually help with drainage. For the trench, how deep does it need to be? And does the pipe need to run the full length of the slope or just near the shed?