Gravel pad

A layer of compacted stone, sized and shaped a specific way

A gravel pad is more specific than the phrase suggests. It isn't just gravel dumped and spread flat. Three things separate a pad that actually works from a load of stone that looks similar but drains and settles poorly:

• Crusher run, not smooth river gravel. The angular particles lock together when compacted, which loose round stone won't do.
• Compaction, not just spreading. A plate compactor or roller packs the material so it stays firm under load instead of shifting.
• A crown in the middle, not a flat surface. Rain has to have somewhere to go, and a flat pad just holds water against the container's underside.

The crown matters more than the depth

A common assumption is that a thicker pad is automatically a better one. Thickness helps, but a flat pad of any depth still lets water sit under the box after rain, and standing water under a container is what actually shortens its life, rusting crossmembers from below and feeding the condensation cycle inside. A properly crowned pad, built so the middle sheds toward the edges, solves the water problem that a thicker but flat pad never does.

Sizing a pad to the container

The pad should run a little larger than the box on every side, so the corners never bear right at the pad's own edge where compaction is weakest. A 20-ft container covers about 160 square feet and a 40-ft about 320, so even the bigger pad is a modest, one-day job for a local grader.

Where gravel fits against blocks alone or a poured slab

A gravel pad on its own gives drainage but not the concentrated bearing strength a corner needs. Solid concrete blocks set on top of a crowned gravel pad combine both: the pad handles drainage, the blocks handle the point load at each corner. That combination is what our crew builds on every delivery, and it's the setup we'd choose for our own containers.

A poured slab or piers only earns its extra cost once a container stops being movable, a converted workshop or office rather than storage. For a box that might move on someday, gravel is also the reversible choice: pull the container off in a few years and you're left with a clean parking pad instead of concrete to break up.