Design Considerations before building a pool

(project: Alberto Apostoli Architect)

When designing pool areas, it is important to remember that people interact differently when minimally clothed. This means there is an increased need for personal space. Special consideration should be given to corridors, passageways and circulation spaces where guests travel in opposite directions. Pinch-points should be avoided, and poolside relaxation spaces should be designed with personal space in mind. If there is food or beverage service offered in these areas, than space for staff to attend to guests and tables for service items should be provided. In addition, benches and seats in the pools need to allow for adequate space between bodies (600 mm is recommended); where possible, it’s advised to provide individual seating so that bathers don’t have to consider invading another’s personal space on a communal bench. Seats should also be shaped to allow for comfort and space where air jets might push the bather away from the seat back. To create a bather-friendly environment, pools should also have sufficiently wide treads and short risers for entries and exits and no sudden drops at the junction with the floor.

Surface Finishes

Surface finishes for pools should be selected based upon several criteria: safety, hygiene, ease of maintenance and visual appearance. Natural stone is a popular finish in pool areas; however, these don’t carry slip-resistance ratings like manufactured tile finishes. Natural finishes, such as slate, should be carefully selected, as many varieties have a tendency to de-laminate, and any marble finishes with fissures should be avoided. Limestone, in all its various forms, should generally be avoided in wet areas, as it is not only very soft and easily eroded, but species like Travertine can be very heavily fissured. Even though these tiles can be supplied with fissures filled with a resin-based material, new openings will inevitably form during use. If choosing natural stone, it’s important to use a testing agency to test slippage. The cost for this is minimal and is highly recommended, as it demonstrates due diligence. Of course, it’s also imperative to choose floor surfaces that minimize the potential for slippage and use the correct sloping angle3 for proper drainage. It’s worth noting that the requirement for non-slip surfaces is only in critical areas, including the treads of the steps and the top of the slope inside the pool down to the deeper areas.

(from left to right: natural stone for a pool by Bi Studio Architects; pool solarium made by travertine )

(A refined and elegant edge, athermal and anti-freeze, created with inserts of mother-of-pearl. A solution totally made in Italy by Carobbio)

Pool Types

The aesthetics of a pool are very much affected by the type of pool chosen. There are two types of pools: overflow and freeboard. An overflow pool is most commonly chosen for hydrotherapy spas because they can be level with the decking or designed as infinity pools. On the other hand, in a freeboard/skimmer pool, the water level is approximately 150 mm below the pool deck, creating a visible edge. Not only do the pools look very different, but they also function differently in terms of how they handle the treatment and flow of pool water. An overflow pool uses a balance tank to store and treat the overflow of surface water that runs off when people get into the pool. The displaced water is captured, treated and then pumped back into the pool. A skimmer pool, instead, does not have the inherent benefit of constantly renewing its surface water because the displacement is handled by the water level rising versus vacating the pool. This means overflow pools are very efficient when it comes to removing and treating polluted surface water. This is important because surface water, which holds approximately 75% of a pool’s pollution, is often ingested by swimmers.

Pool Finishes

Pools are usually finished in tiles, either mosaic or larger format. And non-slip tiles are essential around stairs and shallow areas. Natural stone or slate is not recommended because it is porous and can discolor, leaving a residue on the pool floor. If considering such materials, test them with pool chemicals prior to installation. In order to increase waterproofing, a rendered finish can be used. The rendered finish is applied between the concrete structure and the finish tile. Stainless steel pools are usually left bare (versus tiled) and can be polished to produce either a satin-brushed or mirror finish. PVC liners are often used in large, public pools where there’s a need for an affordable pool finish that is watertight. These flexible membranes can be applied to both concrete and stainless steel pools. They come in various colors.

(from left: Ceramic tiles that recall the oak essence, made by Florim. A steinless steel pool made by Italpool)

Design Considerations

Pools are complex to build and manage. User safety, efficient water treatment and pleasing aesthetics start with careful planning, specification and design. The water treatment system must be an integral part of the architectural, structural, mechanical and electrical design of the building. It is critical at the earliest stages of a project, after determining the type of pool(s) being installed, to consider the following key factors:

• Anticipated bather load (required to determine pool and plant sizing)

• Pool size and volume (length x width x depth), plus any hydrotherapy equipment to be incorporated into the pool

• Pool location

• Balance tank location

• Plant room location and size

• Level of pool, balance tank and plant room are of paramount importance