Gravel Used in Pool Construction

Pool Gravel

• Gravel, whether for pool or any other sort of construction, comes in different types. Two common gravel types in pool construction are #89 gravel and #57 gravel. Pool builder use gravel because it compacts well and is much more stable than sand or dirt around a pool. Pool builders also use gravel around and under pools because it's permeable and aids in draining groundwater away from a pool's basin.

Number 89

• Number 89 gravel is also known as pea gravel, so called because each gravel stone is about the size of a pea. In pool construction, swimming pool builders use #89 gravel to help make up the base to set the pool's basin.Pool builders also use #89 gravel under pool steps and seating areas. #89 gravel's small size allows it to be tightly packed, helping to eliminate any possible air voids under a pool's floor or steps.

Number 57

• Number 57 gravel is larger than #89 gravel, averaging about 1/2-inch diameter. This gravel makes an excellent backfill during pool construction for an in-ground pool's side walls and its relatively large size helps it to lock together for a tightly compacted in-ground pool wall backfill. The #57 gravel also has excellent drainage properties, moving water down and away from an in-ground pool basin's side walls.

Considerations

• Many in-ground pool builders prefer gravel because it helps to speed up the pool building process. When sand or dirt is used under a pool basin's floor or behind its walls it can take weeks or even months to compact properly. Gravel used under a pool basin's floor and as a pool side wall backfill compacts almost right away. Gravel is more expensive In relation to pool sand as a base and as a backfill.