What is the Difference Between a Hot Tub and Spa?

Hot Tub vs Spa

Hot tub house home interior whistler
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Like a spa, a hot tub has built-in jets to provide warmth, relaxation and a massage effect on people's muscles and joints. They both are used for therapeutic reasons and socialization. In the early days—the late 1960s and early 1970s—hot tubs were made from wood, including cedar, redwood, cypress, teak or a composite. In the mid-1970s, the technologically advanced portable acrylic spas were introduced, replacing the wooden tubs in popularity.

Hot Tub or Spa?

Today, the terms hot tub and spa are used interchangeably. Both describe a large tub that is used for relaxation, hydrotherapy, warmth, and entertaining. Both are equipped with built-in jets for targeting bathers' sore muscles. 

Basically, there are two types of hot tubs and spas: portable and custom-built or in-ground. Portable models can accommodate anywhere from two to eight or more adults. They can be inflatable latex or vinyl, which are usually less expensive; fiberglass, acrylic; polyethylene; or another type of plastic. Some hot tubs are built in traditional wood or even out of recycled materials, like metal bins or barrels.

In-ground or custom styles are most often referred to as spas. They can be attached to an in-ground swimming pool or adjacent to a pool and meant to be a sort of hot-and-cool or workout and relax type of experience. Others are stand-alone tubs, but set into the ground or custom built.

Some are sturdy portable models (not inflatable) from top manufacturers that are installed to look in-ground or can be on a raised platform, sometimes under a pergola or a gazebo. Others are custom built and often constructed of the same materials that pools are made of, like concrete, fiberglass, or gunite, along with stainless steel, tile, or copper.

Some spas are customized along with a pool and are in the pool itself, making it easy to pop in and out of the heat of the tub to the cooler waters of the pool.

The word spa is often associated with a health resort destination or a commercial establishment where patrons can also receive aesthetic services, massages, facials, and other pampering treatments.

The term hot tub is more specific in describing that hot, bubbly tub, and has experienced a resurgence in usage to distinguish it from a day spa.

Small hot tubs that accommodate 2 to 3 adults and are designed for a more intimate experience measure about 3 to 4 feet high by 5 feet across and hold approximately 500 gallons of water. Larger hot tubs are around 4 to 5 feet high and 6 feet or more in diameter and are built to accommodate up to 11 adults. They hold about 850 gallons of water.

Hot Tubs in Pop Culture

When referenced in films, TV, or social media, or pop culture, it's more often a hot tub we hear about than the more sophisticated sounding spa. If collegiate or pro sports figures are caught cavorting after hours, it's in a hot tub, not a spa. Remember the old sketches on Saturday Night Live with Will Ferrell and Rachel Dratch as the "hot tub luh-vahs"?

They often hung out at the Welshley Arms Motel's hot tub, where they would harass other guests with their psuedo-intellectual conversations and disgusting meat snacks. And the film Hot Tub Time Machine would never have had the same appeal as Spa Time Machine. Something to ponder.

Also Known As: Spa, wooden spa, Jacuzzi