CoopenTile and Plaster
Concrete pools are the oldest form of building pools. The process starts with digging a hole in the ground and lining the hole with rebar. The main drains, skimmers, return lines, pool lights etc., are set into place. After that, the pool is shot with gunite (or shotcrete), which is concrete that is shot out of a gun or large spray nozzle, and troweled to the finished shape. The tile and coping stones are set in place. As the final step in the pool construction process, the pool interior is sprayed with a wet plaster mix, and troweled smooth. Once the plasterers apply the finishing touches, they start filling the pool with water immediately, as plaster cures under water.
Types of Swimming Pool Plaster
​
It’s been a long time since they could say “You can plaster your pool in any color you want, as long as that color is white”. Pool plaster is traditionally a mix of white Portland cement and marble dust, but there are dozens of additives for strength, ease of application and color. Plasterers can add color additives to produce any shade of plaster, or use quartz, glass or ceramic aggregate to add flecks of specific hues. Pebble surfaces are also popular, using pea gravel sized, or slightly larger pebbles, pressed into the plaster surface.
​
Plaster has Shading Variations?
​
Known as mottling, and distinct from surface stains and deposits, mottling may appear as grayish hued areas. Plaster is not white like milk, it’s white like clouds. Being a natural product, mottling is inherent in any plaster job and should not be considered a defect. There has been much research on the subject in recent years; however no consensus has been reached on the causes and cure of mottling.
​
Plaster is Stained?
​
Different from mottling, stains are usually localized and distinct in color from the plaster. Most stains that are not from organic sources are caused by heavy metals and minerals coming out of solution and depositing themselves. They may also remain suspended in water, providing dramatic new color schemes. Below is a chart listing common metals found in pools, where they came from, and their identifying colors.