Home › Shed foundations
Shed Foundations: Gravel, Blocks, Skids or Concrete?
Some links on this page are affiliate links. If you buy through them we may earn a commission at no extra cost to you. How we make money.
Foundation options compared
| Foundation | Best for | Pros | Cons |
|---|---|---|---|
| Gravel pad | Small to medium sheds | Cheap, drains well, DIY-friendly | Less permanent; frost-proofing takes extra work |
| Skids on gravel | Sheds you might move | Simple, low cost | Not frost-proof; poor on slopes |
| Concrete deck blocks | Slightly uneven ground | Easy to level; no digging deep | Not frost-proof |
| Block-and-timber | Uneven ground | Good airflow underneath | More pieces to level |
| Concrete slab | Large sheds, workshops, heavy equipment | Most durable; long-lasting | Most expensive; hard to DIY |
| Piers or screw piles | Slopes, poor soil, cold climates | Frost-proof options, easy to level | Higher cost |
Based on This Old House's shed foundation guide.
How to build a gravel pad
- Mark an area about a foot wider than the shed on every side.
- Remove sod and dig out about 4 to 6 inches.
- Add landscape fabric if you like, then a compacted base layer.
- Add gravel in layers, compacting each one with a hand tamper or plate compactor.
- Check it's level, with a slight fall away from the center for drainage.
- Set pressure-treated skids or deck blocks on top, level them, and build your floor frame.
What a slab costs
Lawn Love puts a concrete slab at $4.43 to $7.73 per square foot, or roughly $530 to $930 for a 10x12 shed. This Old House recommends 6 to 8 inches of compacted gravel under a slab on clay or loam soil.
Next step: how to build the shed floor on top of your foundation.
Tips that prevent problems later
- Use pressure-treated lumber for anything within a few inches of the ground.
- Don't build in a low spot where water collects.
- In cold climates, set any pier footings below your local frost line. This Old House says at least 12 inches below it.
- Call 811 before you dig.
What will your shed cost?
Our free calculator compares building it yourself, buying a kit and hiring a builder for your exact size.
Open the shed cost calculatorCommon questions
Can I put a shed directly on the ground?
It's not recommended. Wood in contact with soil rots, and the floor will stay damp. At minimum, set the shed on pressure-treated skids over compacted gravel so air can circulate underneath.
How thick should a gravel shed base be?
This Old House suggests excavating about 4 to 6 inches, adding a compacted base, then building up coarse gravel in compacted layers, with the pad about a foot wider than the shed on each side.
Do shed foundations need to be frost-proof?
Most small sheds on gravel, skids or blocks are not frost-proof and can shift a little in freezing climates. Larger sheds, or local codes in cold regions, may call for piers set below the frost line.
Don't design it from scratch
A good set of plans gives you a cut list, a materials list and drawings for every step, which saves money on wasted lumber and time on head-scratching. See our guide to choosing shed plans, free and paid.
Compare shed plan optionsBrowse paid plan packages