Made of an an aggregate and binder, concrete is a composite material used in swimming pool and deck building construction. Because concrete is in liquid form before it dries, it offers the most flexibility in pool design.

The aggregate includes the solid material in the concrete, typically gravel or crushed rocks, along with sand. Portland cement and flyash are usually used as binders. This dry composite is mixed with water to form a very thick liquid. Additives boost the strength or affect drying time, making the concrete easier to work with.

After the concrete is mixed, it is poured into place. For a swimming pool, this means that the pool shape has already been excavated and reinforced. After the concrete is poured and leveled, the curing process begins. Temperatures and moisture must be as stable as possible, to maximize the concrete’s strength and durability. When the curing process is compromised, cracking and other defects are possible.

Concrete can also be used in decking designs. It can be stained, brushed, stamped and textured to mimic natural stone and provide a non-slip surface. Concrete surfaces should be sealed to prevent discoloration, mildew and cracking, and the type of concrete decking and sealer should be selected based on the climate.