What Are the 4 Types of Inground Pools?

Concrete With Plaster or Aggregate Finishes

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Best for: Permanent in-ground pools

Made of steel-reinforced concrete that forms a shell, concrete and plaster are the most common in-ground pool-building materials and were the first ones used when residential pools became popular. The reason: Concrete is durable and porous, which allows the plaster-coated shell to hold water, provide stability, and be replastered when needed, adding to its longevity and durability. Even though concrete has a higher up-front cost (as opposed to vinyl, for instance), it is considered the most cost-friendly option long-term as it can be maintained for years and likely will never have to be replaced if properly cared for.

Here’s how it works: After a hole has been excavated in a yard, the sides and bottom of the hole are lined or framed with rebar (steel rods). These can be sculpted into nearly any shape conceivable (from rectangles and hearts to guitars), along with adding steps, ramps, and other features. After the rebar is positioned, the pool shell is made by spraying a finish using shotcrete or gunite, a combination of sand, concrete, and water that’s sprayed onto a surface using a hose. Once the concrete material is cured, it’s topped with plaster (a combination of cement and marble dust), which may also include colored quartz for aesthetics. Plaster is what makes the pool actually waterproof and is an essential step in the process.

This method helps a contractor in deciding the size and shape of a concrete pool. In most cases, a pool with modern curves should not cost any more than the same-size pool with a more traditional, angular shape.