Gunite is a mixture of cement and loosely compacted stone, sand or gravel fragments. This mixture is sprayed out of a hose where water is added to the mix. To make the more more durable, the gunite is applied over steel rebar or mesh. Vinyl, also called Polyvinyl Chloride, is a type of plastic that combines ethylene and chlorine. Vinyl liner pools use vinyl to cover the main structure of the pool, which is made out of stronger material such as concrete, aluminum or steel.
Although both gunite pools and vinyl liner pools offer flexibility, gunite pools offer more flexibility because gunite can be applied to any shape or size of pool. Gunite pools are also more durable because concrete will crack less often than vinyl will tear. Because of the durability and customization of gunite pools, most public swimming pools use this type of pool. Vinyl liner pools are also flexible because the liner can shape to any pool form. They are limited, however, to the size of the pool. The main advantage of a vinyl liner pool is the cost difference. A vinyl liner will typically run about $15,000-$20,000 less than a gunite pool.
Gunite pools are first formed using wood frames reinforced with steel rebar. Once the form of the pool is set up, the gunite is sprayed into the form, which creates the pool. The pool is left several days to dry. Once the pool is dry, additional designs are added to the deck and floor of the pool. Vinyl liner pools are formed using any strong material such as aluminum, steel or concrete. Once the standard pool is set up, additional features, such as steps, are added. Cement is poured around the pool to stabilize it. Sand or cement is added to the floor of the pool to smooth the pool bottom. The vinyl liner is set to cover the inside of the pool and all wrinkles are removed. The pool can then be filled with water.
Gunite pools are more expensive than vinyl liner pools because gunite requires more work to install, expensive equipment and someone skilled at applying gunite. For example, poolandspa.com quotes the cost of a 16-by-32-foot vinyl liner pool with steel walls at $17,000, while they quote the cost of the same-sized gunite pool at $37,000. However, you will also need to consider the cost of maintenance and repairs. A gunite pool is more expensive, but it is also more durable. A vinyl liner pool is less expensive, but you will have to replace the vinyl liner more often than repairing gunite.
Gunite is durable; however, it will crack, which means you will have to replaster the gunite every 12 to 15 years. Because vinyl is not as durable as concrete, vinyl liner pools require more frequent maintenance and repairs and the vinyl needs regular inspection. Replace any rips or tears in the vinyl immediately; water that leaks behind the vinyl can cause major problems such as cracks, fissures and sink holes. Because the vinyl is held to the pool by the pool water, you must never empty the water. Therefore, you will need to special care when cleaning the water. If you do empty the water, you will need to hire a contractor to reattach the liner. The liner will typically last about eight to 10 years.