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Gravel pad for a shed, hot tub, HVAC unit, or parking area, sized with the correct overhang.
With these inputs:
| Result | Value |
|---|---|
| Gravel needed | 4.28 tons |
| Volume | 2.85 yd³ |
| Pad size | 14 ft × 12 ft |
| Estimated cost | $94 – $171 |
| Structure footprint | 120 sq ft |
| Pad footprint (with overhang) | 168 sq ft |
| Base depth | 5 in compacted |
| Material | Crusher Run / #411 |
| Volume | 2.85 yd³ |
| Weight | 4.28 tons |
| Geotextile fabric | 185 sq ft |
| Timber or edging border | 52 linear ft |
| Material cost | $94 – $171 |
Compact in 2-inch lifts and check for level as you go. A pad that is out of level by more than about 1/4 inch over 10 feet will make shed doors bind.
A gravel pad has to be bigger than the thing sitting on it — one foot of stone past each edge is the standard, so water drains away rather than pooling at the base. This calculator adds that margin automatically and sizes the compacted base for the load involved.
Four to six inches of compacted crusher run for a typical shed. Go to eight or ten inches for a pad that will carry a vehicle, and check the manufacturer spec for hot tubs.
One foot larger than the shed on every side. That margin means roof runoff lands on stone and drains away rather than splashing soil against the shed walls.
Crusher run, also sold as #411 or dense-grade aggregate. Its mix of stone and fines compacts into a solid, level, load-bearing surface — washed stone stays loose and will not do this.
Need the whole roof at once? The free roofing calculator works out roof area, squares, shingle bundles, underlayment, drip edge, ridge cap and installed cost from one set of measurements.