Spa Sales Person to Spa Shopper:
 "Our spas are big sellers. We make them by the thousands. These spa shells are very modern plastics and are "thermally bonded" for strength. The combination of the foam and the shell is very good. There is no better construction than this. All those customers can't be wrong."

Reality:
The spa shell is the one largest, most basic and important component of the hot tub. Since the '80's fiberglass hot tub shell construction has been primarily a composite of three layers. 1. First, High Quality Acrylic (colored hard non-porous surface plastic) 2. Second, a bonding layer of vinyl ester resin. 3. Third, a backing of a heavy fiber glass which is carefully hand rolled underneath the acrylic and bonding layer for strength. A strong support frame is then constructed under the hot tub shell adding support to the shell and forming the walls. The resulting shell and structure is very strong and long lasting. Most fiber glass shells have warranties of 10 to 20 years or even a life-time warranty. If cared for they will probably last much longer. The shell must be built strongly because the weight of the hot tub plus the water and occupants approaches 5000 pounds.

Problems with delamination of these materials were resolved years ago. Fiberglass/acrylic is the industry standard.

The problem is that constructing a fiberglass shell in this fashion is labor intensive and the materials are costly for the manufacturer. It does not lend itself to mass production. Some hot tub companies, in an attempt to decrease costs/increase profits, have experimented with cheaper materials for the shell. Or, they have made the fiberglass shell significantly thinner. The full foam design hot tub is the result of this trend. Full foam is also called "Structural Foam."' Full foam was not originally designed as an insulation system as the sales person may imply. It was introduced to solve the problems that occurred when shells were made of weaker/cheaper materials. The dense foam which fills the space between the shell and the ground supports the weaker/cheaper shell and keeps it from collapsing when it is filled with water. It gets the job done. However, filling the spa full of foam creates as many problems as it solves. Click here for more about "Full Foam" design issues.

The largest selling most common non-fiberglass/full foam design has only a 7 year warranty on the shell. The really weak and most cheaply made "thermally bonded" shells are often white in color and have a row of tiles along the water line. The tile helps mask staining that occurs at the waterline. Waterline discoloration is a reality in thes spas made with really cheap plastic. It is important that the hot tub shopper be aware of this basic information.

Because the shell is such an important component, the Spa Specialist andPacific Spa Sales recommends that you do not buy any hot tub with such a cheaply made shell and/or "full foam" construction.