What is the difference between the various types of pools?
Swimming pools come in three basic varieties: concrete, vinyl-liner and fiberglass. They vary in materials and the process of creation.

• Concrete is the oldest method, and the most labor-intensive on the site. These pools are completely built on the site with steel-reinforced concrete. This allows almost infinite design flexibility.

Pool builders can use one of three methods to create a concrete shell: guniting, shotcreting and pouring concrete. The most common — gunite and shotcrete — are pneumatically applied, that is, they are applied with air pressure. The concrete is shot out of a nozzle and piled onto the earthen walls of the excavation and over the steel rebar reinforcement.

Pneumatically applying concrete was not the first method used to create a concrete shell. Originally, concrete pools were made of poured concrete, meaning workers create a set of forms and pour the concrete into the forms to hold it into vertical walls. Shotcreting and guniting became the most common methods of concrete construction because they don’t require forms, making it quicker, less labor-intensive and less expensive than pouring concrete.

Like all concrete structures, these pools can last decades when properly constructed. Improperly constructed, however, they can crack from ground movement caused by freeze/thaw cycles, high water tables, hillside locations or seismic activity. The cost goes up in areas with these conditions because extra reinforcing is needed to prevent movement. Because these pools are constructed entirely on the site, the quality depends on the job’s craftspeople.

• Vinyl-liner, or package, pools are less time-consuming and, in some regions, a less expensive method of construction. Installation of these pools requires assembling pre-manufactured wall panels and supports, then covering the hole with a vinyl liner. These pools are especially popular in cold-weather states because the panels have a certain degree of flex and hold up well under freeze/thaw conditions without extra reinforcement — or extra cost. Some people prefer the feel of the vinyl surface and believe the liners hold up to chemically treated water better than concrete. The components are pre-manufactured, which creates design limitations. But it also means that part of the quality control is in the factory.

Wall systems generally are made of steel, polymer and aluminum. The most common (steel) is the least expensive, but can be subject to corrosion. This problem is becoming more and more scarce because manufacturers offer galvanizing and other treatments to prolong the life, with some manufacturers even offering lifetime warranties. Polymer walls are more easily formed into unusual shapes than metal and are said to better withstand ground conditions, but are more expensive. Aluminum is a strong material and the panels are lighter, making them easier to install and less expensive to ship. These panels are said to hold up well under various ground conditions, except acidic soil. However, aluminum wall systems are rarely used because of their expense.

• Fiberglass pools are said to boast the benefits of concrete and vinyl — that is, the permanence of concrete, with the soft feel, flex and chemical imperviousness of vinyl-liner pools. The nonporous material also is said to resist staining from algae or other factors. Its cost is comparable to, or higher than, similar concrete pools. But manufacturers and installers say the cost is offset by lower maintenance. Vinyl-liner pools are completely manufactured in a factory. This centralizes quality control, but it also limits shapes and sizes to those offered by the manufacturer.

Fiberglass pools are the quickest and easiest to install because they come in one or, rarely, two pieces that simply need to be set in the hole and plugged into the plumbing and electric.

What is the process of shopping for a pool like?
The duration of the entire process, from first appointment to final product, can take a matter of weeks, months or years, depending on the complexity of the project.

How long a consumer takes to “shop” among builders depends on that consumer and how many builders they want to meet.

The time required for design itself varies greatly. Some clients choose from a selection of previously designed, or template, pools. Others want a custom-designed aquascape and want to have input at every stage. In some cases, design continues during construction, whenever clients wish to make last-minute adjustments or additions. Design time also depends on how the builder works. Some offer template pools or design the pool in front of the homeowner during their first meeting. Higher-end builders will meet with customers several times during the design process.

How long does it take to install a pool?
Timelines depend on a number of circumstances, such as the type of construction (shotcrete/gunite vs. vinyl or fiberglass); complexity of the project; weather conditions; the number of clients already being served; and availability of subcontractors. On a project where a home or other building also is under construction, having to schedule around other trades may hold things up.

• Concrete (shotcrete, gunite, poured concrete) construction will take the longest because the entire product is created on site from basic materials such as concrete, steel rebar and plumbing. A basic pool (rectangular, no waterfeatures) on a property with an existing home can be built in four to six weeks, depending on the region. This timeline also assumes there is no interruption, everyone is immediately available and there are no scheduling, delivery, weather glitches or change orders — meaning clients change their minds about something or decide to add on something extra.

Completion may be delayed by rain or snow. Builders in cold-weather states generally try to complete construction before freezes hit. Sometimes, however, builders may have to stop construction midway until the weather warms up.

Project complexity and scale also have a tremendous effect on the timeline for concrete pools. While a basic pool may take only a few weeks, more intricate, large-scale pools have been known to take months and even years. Every stage, beginning with excavation, will take longer than with a small, basic pool. Also, some materials require extra time: Surfacing a complete pool with glass mosaic tile, for instance, can take weeks on its own because it is such meticulous work.

• Vinyl-liner pools are assembled with wall panels made in a plant, so their installation generally happens more quickly. Under ideal conditions and without interruption, a basic vinyl-liner pool can be put together within two weeks after breaking ground.

• Fiberglass pools are the most complete product when they enter the site. They are completely manufactured in the factory and only need to be dropped into an excavation and hooked up to the plumbing and electricity. Under ideal conditions and without interruption, one-piece fiberglass pools can be up and running within two weeks of arrival on the site.

How long will the pool last?
This depends on several variables, including the type of pool installed, the quality of the installer and the manufacturer. Properly installed concrete pools have lasted several decades. But this requires that the pool be properly engineered and built. Some package-pool manufacturers offer lifetime warranties on their panels, and fiberglass manufacturers say the fiberglass makes their product inherently permanent.

How long before I have to redo the surface?
There are as many answers to this question as there are pool surfaces:
• Tile and stone surfaces, considered the most permanent, can be expected to last decades. Some tiles or stones may have to be replaced and reinstalled if they pop out. The grout should last approximately 20 years.

• Plaster, the most common surface for concrete pools, needs resurfacing approximately every 12 to 15 years.

• The life of a vinyl liner depends on the quality of the liner and how well the water chemistry is balanced. Putting a cover on the pool also will extend the liner’s life. By some accounts, a vinyl liner’s life span is anywhere from six to 15 years. Some are guaranteed to hold water for up to 20 years. However, homeowners may want to replace them sooner as patterns begin to fade.

• Pebble and other aggregate surfaces are said to last as long as 15 to 20 years.

• Paint usually needs reapplication within three years.

• Fiberglass pool manufacturers say their pools never need resurfacing.