If you want something cleaner and more reliable than a rock-and-mud swimmmin' hole in your backyard and more permanent than an above-ground pool, there are three main types of inground pools. While wood is a possibility, the cost for one that would not deteriorate in a few years narrows the choices down to the most popular and efficient. Keep in mind that there are variations of the three main types, allowing you more options.

1. Concrete with Plaster or Aggregate Finishes

Using steel-reinforced concrete to form a shell, concrete and plaster are the most common in-ground pool-building materials and were the first ones used when residential pools became popular. Why? Concrete is durable and porous, allowing the plaster-coated shell to hold water, provide stability, and to be replastered when needed, adding to its longevity. 

Here's how it works: after a hole has been excavated in a yard, the sides and bottom of the hole are lined or framed with rebar (steel rods) . These can be sculpted into nearly any shape conceivable (from rectangles to boomerangs to hearts and guitars), along with adding steps, ramps, and other features.

After the rebar is positioned, the pool shell is made by spraying a finish using shotcrete or gunite. This spray-on method helps a contractor in deciding the size and shape of a concrete pool. In most cases, a pool with modern curves should not cost any more than the same-size pool with a more traditional, angular shape.

Alternative finishes besides plaster have become increasingly popular, like pebble aggregate or (Pebble Tec®, a glass alternative Beadcrete®,  WetEdge’s Primera Stone®, NPT’s JewelScapes®,  StoneScapes®, and QuartzScapes®). Expect these aggregate finishes to last about 8 to 12 years.

2. Fiberglass

A swimming pool made of fiberglass will be sold as a large one-piece shell that arrives at your home by truck and then is positioned in the excavated hole with the help of a crane. Unlike concrete pools, fiberglass pools are ready-made, making it rare to request a customized design. Most fiberglass manufacturers offer many models and sizes to choose from. Steps, spas, and benches are usually preformed.

Fiberglass makes the pool-building process quick and easy. Its smooth interior surface is slick, making it tough for algae to cling to. However, fiberglass can be more costly. After 10 to 15 years of exposure to sun and chemicals, the fiberglass deteriorates. Recoating it is not easy, because the new coating does not stick easily to the older one.

3. Vinyl

Pools that are lined with vinyl are built with metal or plastic frames above ground or set into the excavated hole. Prefab supporting walls or panels made of plastic, steel, or aluminum are joined to the frame, making a form that is then lined with heavy vinyl to form the pool shell. The bottom of a vinyl liner sits on a bed of sand or other material, while the top is held down by the coping, which creates a finished edge and also acts as a border for the pool deck.

Like other materials, vinyl deteriorates with longtime exposure to the elements along with pool chemicals. Some liners come equipped with fungus and UV inhibitors, which can extend the life of a vinyl liner from 10 to about 18 years or so.

4. More Things to Consider

Things to Consider Before Diving in to a Pool Project

Read This Before You Build a Pool

Diary of a Pool Project in Pictures

How to Inspect for or Detect a Pool Leak

How to Find the Best Pool Service

10 Smart Reasons for Having a Saltwater Pool

Swimming Pool Design Gallery