Paver Base Calculator

Two layers, two calculator runs

The base layer is crusher run (also sold as dense-graded aggregate, or DGA) — a mix of crushed stone and rock dust that locks together into a dense, load-bearing surface when compacted. It carries the weight of foot traffic, furniture, or vehicles and stops the pavers from settling unevenly.

The bedding layer is concrete sand, a thin, screeded-flat cushion the pavers sit directly on. It lets you fine-tune the final surface height and gives each paver a uniform seat — but it isn't structural. The gravel base does the load-bearing work; the sand just provides a level bed to set pavers into.

Because the layers use different materials and depths, plug each into the calculator on its own — gravel base first, then sand bedding — and add the two results together for your total order, keeping them as separate line items when you buy.

How deep should the gravel base be?

Base depth depends on what sits on top of it. For a patio, walkway, or anything that only sees foot traffic, plan on 4-6 inches of compacted crusher run. For a driveway, parking pad, or any surface vehicles use, go to 8-12 inches — the extra depth spreads tire loads out so the subgrade underneath doesn't deform.

In climates with real winters, add depth on top of those numbers. A shallow base can heave as the ground freezes and thaws, cracking joints and pushing pavers out of level, so lean toward the deep end of the range — or check local frost-depth guidelines — if you're in a hard-freeze zone.

The sand bedding layer: thin on purpose

The bedding layer is exactly one inch, screeded flat with a straight board dragged across screed rails. Not two inches, not "however much makes the pavers sit level." A bed thicker than about an inch stops acting as a leveling cushion and starts behaving like loose fill — pavers rock, rut, and migrate under traffic because they're sitting in sand instead of on a firm base. If a section of the excavation is low, add more compacted gravel base underneath rather than piling on extra sand; the sand stays at 1 inch everywhere.

Use coarse concrete sand meeting ASTM C33 for bedding — it's angular enough to compact and drain properly under pavers. Skip mason sand and play sand here; they're finer and rounder, so they hold water, compact less predictably, and let pavers shift more than proper C33 bedding sand does.

Running the numbers

The calculator does this automatically, but it helps to see the formula so you can sanity-check the output or adjust for an odd-shaped patio. Convert depth from inches to feet by dividing by 12, then:

cubic yards = (length ft x width ft x depth ft) / 27

From there, tons = (cubic yards x pounds per cubic yard) / 2000. Crusher run and concrete sand both run about 2,700 lb/yd3; mason sand and #57 stone are lighter, around 2,410 lb/yd3. See the yards-to-tons conversions guide for more density references.

Worked example for a 12 ft x 10 ft patio: the gravel base at 6 inches compacted is (12 x 10 x 0.5) / 27 = 2.22 cubic yards, about 3.0 tons of crusher run. The sand bedding at 1 inch is (12 x 10 x 0.083) / 27 = 0.37 cubic yards, roughly 0.5 tons of concrete sand — two calculator runs, two very different totals from the same footprint.

Compaction and ordering extra

Crusher run compacts significantly — figure on roughly a 20% reduction in volume once it's tamped down. Loose material spread at your target depth will settle thinner than planned, so order extra to make sure the finished, compacted depth matches your calculation. Compact in lifts of about 2-4 inches with a plate compactor rather than dumping the full depth at once; over-thick lifts leave the bottom under-compacted even when the surface looks solid.

The sand bedding layer is screeded, not compacted, so it doesn't need the same overage — order it close to the calculated amount, rounding up slightly for waste.

Weight, hauling, and prep

Both layers are heavy. A cubic yard of crusher run weighs about 2,700 lbs — more than the rated payload of most half-ton pickups in a single load, even though it won't look like much in a truck bed. For anything beyond a couple of cubic yards, bulk delivery is usually safer than repeated truck runs.

• Excavate deep enough for the full stack — base depth, plus 1 inch of sand, plus your paver's actual thickness — measured down from the finished grade you want.
• Slope the base about 1/8 inch per foot away from any structure so water drains off instead of pooling against a foundation.
• Lay geotextile fabric over soft or clay-heavy subgrade before placing the base, to keep the crusher run from working its way into the soil.
• Install edge restraints (plastic, metal, or paver-specific edging) around the perimeter to stop the base and sand from spreading outward under load.
• Finish with polymeric sand swept into the joints after the pavers are set — a separate product from C33 bedding sand, used to lock pavers together at the surface.