Spa pool buyers guide: spa pool shell construction

When shopping for spas, at the top of your checklist should be "a good quality spa shell". While other parts of the spa can be repaired or replaced, when it comes to the shell - if anything goes wrong, you're stuck with it.

If a spa pool pump or jet malfunctions, they are relatively easy and inexpensive to repair. If the spa pool shell delaminates, your entire investment could be lost.

Spa pool shells are formed by heating a flat sheet of coloured acrylic in an oven and then drawing it into a spa mould. After forming, the acrylic sheet becomes very thin – in some places less than 1mm thick. As a result, the acrylic must be strengthened using fibreglass.

Because acrylic has a very smooth surface, the first layer of fibreglass must use a special vinyl ester resin, which actually melts itself into the back of the acrylic. If this resin is not used, your spa pool can delaminate over time. Make sure the spa pool you purchase uses this vinyl resin.

As an additional quality assurance measure, a few manufacturers cure the shells in a temperature and humidity controlled curing oven. This step increases the price of the spa but if this step is missed; the spa pool shell may delaminate, even if vinyl ester resin has been used. Most spa pool companies do not have this critical technology in their manufacturing process.

Take Away:

  • Ask about the warranty before you buy. When shopping, the best way to make sure your spa pool shell construction meets these recommendations, is to make sure the warranty is as long as possible and that it is non-pro rata. The industry standard is as low as two years.
  • It pays to have a longer shell warranty and a few of the better manufacturers offer ten years.
  • Lastly, make sure the company you purchase from has been around for a while so you can be sure they will be around to honour a warranty.

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