AsphaltTons.com — asphalt tonnage calculator

How Much Crushed Stone for a 7x7 Hot Tub Pad?

A 7 by 7 foot hot tub pad covers 49 square feet. At 6 inches of crushed stone, plan on 0.91 cubic yards, or about 1.3 tons, which answers how much crushed stone for a 7x7 hot tub pad.

Volume and tonnage calculator →

The math

  1. Area: 49.0 sq ft.
  2. Depth in feet: 6 ÷ 12 = 0.500 ft.
  3. Cubic yards: 49.0 × 0.500 ÷ 27 = 0.91 yd³.
  4. Tons: × about 1.4 tons per yard = 1.3 tons.

The crushed stone calculator does this for any size.

Crushed stone needed by depth

DepthCubic yardsTons of crushed stoneTons +10%
4 in0.600.80.9
6 in0.911.31.4
8 in1.211.71.9

Building the hot tub pad base

Hot tubs are heavy once full of water and people. A compacted stone pad of about 4 to 6 inches, perfectly level, works for many tubs, but check the manufacturer’s base requirements before you build.

Prep

Remove sod and roots, level the area and slope it slightly for drainage. Install edging so the stone stays inside the footprint.

Getting it delivered

If you haul it yourself, a typical half-ton pickup should carry only about half a cubic yard of stone, well under what the bed looks like it can hold. Crushed stone has angular faces that lock together under a compactor, which is why it holds a pad shape. Round up by about 10 percent for compaction and uneven ground.

Planning the cost

Stone is usually priced per ton or per cubic yard, and delivery is often a separate charge based on distance. A full truckload can cost less per ton than a partial one, so it can pay to combine projects. Ask whether the quote includes tax, delivery and any small-load fee before you compare yards.

Measuring the area

Measure length and width in feet at a few points and use the largest figures, since real sites are rarely square. For odd shapes, split the area into rectangles and circles, work out each one and add them together. Depth is the number most people underestimate: drive a stake, run a level string and measure down to the dug-out surface in several spots.

Questions people ask

How many tons of crushed stone for a 7x7 hot tub pad?

About 1.3 tons at 6 inches deep.

How many yards of crushed stone for a 7x7 hot tub pad?

About 0.91 cubic yards.

How many tons of crushed stone are in a cubic yard?

Roughly 1.4 tons for planning, but suppliers vary with stone size and moisture.

Should I put landscape fabric under the stone?

On soft or clay soil, a woven geotextile keeps stone from sinking into the dirt and makes the layer last longer.

Related guides

Open the volume and tonnage calculator → Asphalt tonnage calculator →

As an Amazon Associate, AsphaltTons.com earns from qualifying purchases. Product links below are sponsored.

Related answers