Construction methods for private pools

There are several distinct construction methods for private (home) swimming pools, which are typically called "concrete", "vinyl liner", and "fiberglass". The term "vinyl liner" pool describes the method of lining the interior, not the construction materials, which may be concrete (of various types), pressure-treated wood, galvanized steel wall system, structural foam (polymer) wall system, and recently introduced, fiber reinforced composite wall system.[1][2][3]

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Fiberglass Pools

Concrete pools have many different construction methods, as the term concrete describes the basic materials used in construction, and fiberglass refers to the base material of the pool shell which is fiberglass reinforced resin generally 5 mm in thickness. As these terms refer to different parts of the pool the names may be confusing to the newcomer to the swimming pool world. Construction standards for in-ground pools have been developed by the Association of Pool & Spa Professionals (APSP) and approved by the American National Standards Institute.

According to Aqua Technics, a major fibreglass pool builder based in Western Australia that exports to 17 countries worldwide, a fibreglass pool should be constructed with multiple layers, incorporating a gelcoat layer. This ensures the pool is structurally sound and resilient to the elements, thus preventing fading caused by exposure to pool chemicals and ultra-violet light.

The layers of a fibreglass pool should typically include six layers; a Gelcoat Interior Surface Layer, Corrosion Barrier, Primary Structural Layer made from high quality fibreglass resin, Maxi-Strength Structural Layers incorporating specialised enhancers and an inert ceramic and the Outer Finishing Coat which seals the pool and offers the final barrier from damage caused by external elements. Each vital layer in the system should be individually adhered to the next using a Matched Lamination System. This sophisticated method ensures maximum bond and prevents gradual separation of the pools layers, known as de-lamination.

Extensive research in fade-resistant technologies for fibreglass pools in recent years has seen the development of manufacturing processes that guarantee a pools surface finish will not fade, meaning fibreglass pools are now available with colour that last for many years.

There are benefits to installing a fibreglass pools including the relatively short installation time and financial savings compared to concrete pools.

Concrete pools

Concrete pools may be constructed using many differing methods. Concrete pools are not dissimilar to concrete ships: i.e. they are a contiguous shell that will float under certain circumstances. It is therefore essential that an unrestricted hydrostatic valve is incorporated in the pool design. It is not advisable to empty these pools unnecessarily – especially during rainy months – as the operation of the hydro valve is necessary to avoid flotation (and possible destruction) of the swimming pool. The emptying of all pools must be conducted strictly under the supervision of the pool builder or an authorized consultant.

Concrete pools offer greater design flexibility than fibreglass pools and can be constructed in any size, style or shape. This makes them ideal for more challenging sites such as those with limited space, narrow blocks and hillside locations. The ability to individually design a concrete pool means the consumer is not limited to pre-moulded designs. Concrete pools can take on any form including L-Shaped, Geometric, Freeform, Lap Pools and Out-of-Ground pools.

Concrete pools are constructed completely onsite to custom specifications. As such, they take approximately two months to build. The concrete pool construction process includes;

  1. Set out and pre-start meeting
  2. Delivery of materials for form work
  3. Earthworks and hole digging
  4. Formwork and steel placement
  5. Concrete shell pour
  6. Backfill and plumbing
  7. Electrician
  8. Waterline tiling
  9. Step treads
  10. Bull-nose header on pool edge
  11. Water features and paving
  12. Filtration equipment delivery
  13. Shell clean out and plaster delivery
  14. Internal finish application
  15. Fill with water
  16. Chemical treatment
  17. Client instruction and handover

Vinyl liner pools

As mentioned above, vinyl liner refers only to the interior surface of the pool, as colorized chlorinated PVC thermoplastic vinyl may be used as the waterproofing membrane in a number of diverse pool construction methods. Vinyl Liner pools are typically more numerous than other in-ground pool types, especially so in European Union countries, including the UK, Canada and New Zealand.

They are very popular in the Eastern and Southern United States, where this pool type is considered to be a less expensive option to gunite concrete and can be quickly installed during a single week. These pools still provide a durable, quality product that can last for several decades. Designed by Cascade Industries engineer Bob West and introduced to the New Jersey public in 1948, the package pools were introduced to the wider American public by Cascade's (c. 1948–1980) VP of sales Ed Gorman by inclusion the 1951 Sears Roebuck catalog as a do-it-yourself project for US$500.00 + delivery and installation.

In the following years many manufacturers worldwide have produced vinyl pool kits of varying styles and quality that can be transported to sites and installed in only a few days. Designs range from simple (and inexpensive) prefabricated wooden, galvanized steel walls, structural foam (polymer) walls, to the latest high-quality, high-tech fiber reinforced composite wall system from Only Alpha Pool Products[4][5]. Vinyl liner pools are popular with many pool buyers due to lower initial cost, better insulation, the many liner patterns and colors available, a child friendly embossed non-slip finish, and the fact that the liners are treated to discourage algae growth. Most chlorinated PVC thermoplastic vinyl pool liners are .20" and .30" gauge (5.0 mm & 7.5 mm) and are recyclable when they reach their design life (usually 20 to 25 years in moderate climates). Replacement liners can be installed in one to two days, and providing the basic pool shell is of substantial construction, a pool may have several new liners over its expected life, which could be as much as fifty years in the case of a concrete construction.

Vinyl liners in sunny climates like Temecula, California, only last about 7-12 years. They then begin to crack and must be patched. This is due to the heat and strong sun.

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