History of the Hot Tub Industry

The history of the modern spa is quite an amazing story with many trials and errors. People have enjoyed the therapeutic and social benefits of hot tubs since ancient times, but the spa industry, as we know it today, all started in the Sunshine State of California.


In 1956, the Jacuzzi brothers invented the first portable hydrotherapy pump, later to be known as J-300, and could turn any bath tub into a spa-like atmosphere. Their invention was brought about because a child in the family was receiving hydrotherapy treatment for arthritis in Berkeley, California 65 miles from the child’s house. The invention of the J-300 saved the family hours of traveling and discomfort.


In the 1960’s, the first home hot tubs started to appear in the form of old wine vats, tanks, and barrels in the wine country of Northern California. People were taking these old discarded vats and filling them with hot water. They had no seats or lounges and the giant ones could fit 20-30 people, at once, all enjoying good company and the fun of hot water. In Southern California, gunite, or cement, spas were amazingly popular. They were built attached to in-ground swimming pools, and for this reason was expensive to build. Each one was different because they could not be mass produced. They were each designed, built from the ground up, and had only one jet.

Later, in 1968, Roy Jacuzzi invented the modern whirlpool bath he called “the Roman.” It had fully integrated plumbing, jets, and 50/50 air-to-water ratio bringing the portable hydrotherapy pump to the next stage.

In 1969, Len Gordon was the first to mass-produce spas using fiberglass. Using a mold, he sprayed a non-stick separating agent into the mold followed by a gel-coat, and then fiberglass for structural strength. Everyone started using this method because it changed the building recipe. Instead of building from the ground up, once the hole was dug the production was almost finished. It was something even the average paid worker could afford.


Throughout the 70’s wooden hot tubs were better known than fiberglass and held onto a hefty share of the market supporting 15-20 manufacturers. If a customer was asked to picture a hot tub, a wooden design is what they would answer. In 1974, California Cooperage improved the wooden hot tub with liners, and better plumbing. Their marketing strategies also improved with ads in places like Playboy Magazine.

The production methods of the gunite spas limited the growth potential. It could take up to two weeks to build one if everything went well. For this reason the gunite spas were not only time consuming, but also costly.

The fiberglass spas were the hot new product that everyone wanted to have and sell. People would take an existing mold, make a copy, and sell it. This process was called “splashing” and was legal in California at the time. Because of “splashing,” many fly-by-night companies were started and very careless products were produced because there were no uniform codes and regulations.

The 70’s and 80’s were known as a massacre because major surface problems occurred such as blistering, crazing, delamination, and gel-coat cracking. Major companies at the time suffered up to a 90% failure rate with angry customers wanting compensation. Many companies went broke trying to make good on the warranties.

Some companies were selling acrylic hot tubs as early as 1973. However many companies didn’t get into acrylic right away because the expense of buying the machines were very costly. But even blistering problems arose with the acrylic and it was the boat industry that found the solution; switching from a polyester resin to a vinyl ester resin. This discovery dramatically increased sales and saved the industry.

In 1979, a law was passed making “splashing,” or copying tub designs, illegal. This eliminated the fly-by-night operations making the serious manufacturers credible and trustworthy to the consumer.


In the early 80’s, the wooden hot tub sales diminished to nothing. There were rumors that they leaked, the wood caused disease, and rotted. However, these were just rumors by other manufacturers to get their business. Ultimately, it was the convenience of the plastic man-made shell spas, for the dealers, which caused the downfall of the wooden tub trade. The wooden hot tub had to be built into the ground and took the dealer two days to set up. A dealer could install 8 plastic spas in the same two days saving time and money. In 1985, a mass-produced spa component package, called the Spa Pack, changed everything. This changed the industry sale type from contract to retail store. Before the Spa Pack, the installation was piecemeal. The components came separate and were often times installed by the consumer. A sound installation was a chance of fate. The Spa Pack was the answer that brought the build to a two-line hookup from a piece by piece build. The Spa Pack fit in the space allotted and would come to accommodate either a 120V or240V electrical service. The 240V allowed for enough amps to run both the pump and the heater so the heater wouldn’t be turned off when the pumps were turned on. From the Spa Pack came the portable spa.


In the space of 20 yrs, the spa industry claimed an established position in the national culture and hit an astonishing sales peak of 280,000 units.


Wooden hot tubs are still a part of the business making up 10% of total industry sales. Now, with all the technology and advances made over the years, a relatively new addition to the spa history is here to stay called a Swim Spa.


A new product enters the market called the Dual Temperature which allows users to combine a Swim Spa for Swimming against the current of jets in 80 degree water and being able to relax in their hot tubs at 104 degrees.


The public becomes knowledgeable and aware of Swim Spas.