How much does lava rock weigh?

Lava rock averages about 0.55 tons per cubic yard, much lighter than most stone.

How deep should lava rock be?

A 2-3 inch layer is typical for decorative coverage.

It does not break down like mulch, but it may need occasional cleaning or top-up as soil and debris accumulate.

Inputs

Change any field and the results update instantly. Use supplier specs when you have them.

LengthftWidthftDepthinDensitytons/ydPrice per ton$Price unit

Tips & notes

Assumptions that most often change the final quantity in the field—so you order with clearer eyes.

Use landscape fabric below lava rock to reduce soil mixing and weeds.

Wear gloves because broken lava rock can be sharp.

Use edging to keep rock out of turf and walkways.

Avoid piling rock against heat-sensitive plants in hot climates.

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