By Barry Justus
The first pools were built 5,000 years ago in modern-day Pakistan. Waterproofing the pool interior was accomplished by using a combination of bricks, mortar, plaster, and a coating of tar. In 2500 BC, the Romans refined the process with massive public bathing pools that were built to impress. Columns, terracotta, and mosaics were featured in the finish materials for these pools. Modern swimming pools first appeared in Britain in the mid-1800s and often featured an all-tile interior, a material that is in resurgence today in high-end pool projects.
Arguments about the various types of pool construction and interior finishes are endless. Selecting the right one depends on a number of factors as many interior finishes have increased in cost and complexity in the last decade. Regional variances, product/applicator availability, and budget are the usual constraints when it comes to choice.
Many in the industry have witnessed pools that have been lovingly maintained by meticulous owners whose plaster or vinyl interior has lasted well into its third decade. Many have also observed the complete failure of a pool project that can sometimes be measured in years, or even a few months, due to neglect or incompetence on the part of the pool owner or the installer.
What determines longevity?
The longevity of a swimming pools’ interior finish depends on a number of factors, such as:
- Water chemistry, long-term;
- 28-day water start-up;
- Ultraviolet (UV) light and weather exposure;
- Structural integrity of the shell;
- Water penetration;
- Site conditions;
- Preparation of the surface;
- Application methods; and
Regular water chemistry maintenance has the largest effect on the pool’s interior finish. Problems with pH, alkalinity (TA), and other chemical components, directly affect the pool’s interior. Therefore, it is imperative pool owners are given instructions on proper water chemistry practices and applications.
The popularity of salt chlorine generators and the resulting corrosive nature of salt can also affect the interior finish. It is normally advisable to delay the introduction of salt until the completion of the 28-day water start-up period in plaster pools. In many cities, and in particular rural locations, the quality of the initial fill water can also be problematic. By trucking in suitable fill water it will more than compensate for the aggravation of staining and mottling that can occur on different types of pool interiors—especially since most are susceptible to these problems during the initial curing stages of cement-base products.
Simply filling the pool in a timely manner can also alter the longevity and appearance of its interior. For instance, fibreglass pools need to be filled as they are backfilled, while vinyl pool liners are often ‘stretched’ into place by carefully adding water. Concrete pools, on the other hand, should be filled slowly and steadily—too slow and there are risks of staining and scum lines, while too fast can cause structural problems.
The ‘start-up’ or 28-day cycle of a modern plaster pool is critical to its longevity. As such, many courses are available that teaches industry professionals proper start-up procedures and techniques. The one common denominator is that it is worth the price of hiring a professional to oversee this process. Leaving start-up procedures to the pool owner can lead to problems down the road with esthetics and longevity, not to mention warranty issues. It is always best for the consumer—in addition to the company’s bottom line—to hand over the pool in a working, balanced, and safe condition.