Lava Rocks for a Rectangular Fire Pit

`Wt = L* W * Dp*(22" lb/ft"^3)`

Enter a value for all fields

The Lava Rocks for a Rectangular Fire Pit calculator computes the pounds and number of bags of lava rocks needed for a rectangular fire pit.

INSTRUCTIONS: Choose units and enter the following:

(W) Width of Fire Pit
(L) Length of Fire Pit
(Dp) Depth of Lava Rocks in Fire Pit

Lava Rocks for Fire Pit (Wt): The calculator returns the weight of the lava rocks needed in pounds and the approximate number of 5, 6, 10 pound and 12 pound containers (cartons, pails or bags).

The Math / Science

Fire pits work on propane or natural gas and they provide warmth and atmosphere to your outdoor landscape. Your fire pit needs to diffuse the gas on the fire pit surface through an attractive BUT non-combustible material like lava rocks or glass.

The Stone or Glass for a Round Fire Pit calculator computes the number of bags of lava rocks or exotic glass needed for at round fire pit based on the dimensions of the fire pit and depth of material (glass or lava rocks). The approximate density of spread lava rocks is 22 pounds per cubic foot, but this can vary based on the spreading (loose vs. tight) and the size of the rocks.

The Math / Science

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