How Are Hot Tubs Made?

With so many parts and features working in tandem to bring our customers so much joy, we’re sometimes asked the questions: “How do hot tubs work?” and “How are hot tubs built?”. We attempt to answer both of these questions in this article. If you have any more questions, feel free to contact us and we’ll try to our best to give you a professional answer.

What Are Hot Tubs Made From?

Hot tubs and spas can be made from stainless steel, cement, fiberglass, or PVC (inflatable).

Whatever shell your hot tub may be made of, they all have their share of strengths both aesthetically and functionally. Your hot tub shell is made to keep all of the water contained inside your tub. Additionally, it is a big factor on how well your hot tub is able to retain heat – as it needs to be strong enough to withstand years of use.

Hot Tub Shell Materials

A hot tub shell is made from several different types of material. Some hot tub shells are made from vinyl, acrylic, or even rotomolded plastic. Hot tubs used to be made primarily out of wood, but the materials mentioned above are now more sustainable in order for your hot tub to last longer.

Acrylic is one of the most common materials you will see a hot tub made out of. Acrylic shells are made from a single sheet of acrylic and are reinforced by resin and fiberglass. Other hot tubs can be made from vinyl, which are constructed by putting a vinyl liner over a frame made from an additional material like cement. Those made from material like rotomolded plastic means the material is a plastic powder with a dull matte finish – and unlike acrylic, are very lightweight.

See How Hot Tubs Are Built

A hot tub shell is built in order to retain heat and stay well insulated. Hot tub shells are built to be durable and energy efficient, consisting a high quality multi-foam density in order to withstand the test of time. The video below shows an overview on how our Master Spas hot tubs are built and formed.

When building an acrylic hot tub, you start with a sheet of rigid acrylic that is rested over the mold of a hot tub. From there, it is transferred to an oven, where the heating elements on top and bottom bake the sheet until it is soft and malleable. From there, the sheet is transferred back to the mold and essentially vacuumed sealed, so it takes the proper shape. Paint, resin, and fiberglass are then applied to reinforce the acrylic sheet.

Once all air pockets are taken out of the fiberglass, insulation is applied on the underside, holes are drilled for jets to then be installed, and PVC tubing, hoses, motor, and electrical elements are installed.

How Do Hot Tubs Work?

Hot tubs are self-contained vessels that provide a relaxing and stress reducing environment for those using one. Essential operations on how hot tubs work is pretty much the same – as they all have a large mechanical construction that allows operations such as heating, etc.

In order to answer the question “how do hot tubs work?” you need to know the main components of one:

The Shell: As described above, the hot tub shell holds the water, has been molded to have a variety of different seats, has multiple jets installed inside it, and insulation sprayed on the underside to help retain the heat.

Pumps: Pumps circulate water in and out of the hot tub which help to operate and filter the jets. Low speeds on pumps filter and help to heat – and are controlled by the spa pack which is regulated by the thermostat. High speeds on pumps operate the jets, are also controlled by a spa pack air button, which allows high pressure steam.

Jets: Air is drawn through a constricted section of the jets (i.e. the nozzle) and creates a pressurized effect that creates soothing and massaging element for the user.

Spa Pack – Controller and Heater: We mentioned the Spa Pack above in regard to the pumps. It contains a heater and controller – the controller allows the pump, filter, heater and jets to provide filtering, watering jets, and heating. Every time the water is circulated through the heater, it heats up the spa.

Filters: Filters are crucial when it comes to keep the hot tub water clean and clear. Follow maintenance instructions,

Topside Control:Changing water temperature is easy with the topside control – as it controls, most importantly, the heat of the water temp, and also the blowers, lights, and pumps. Make sure the water temp never exceeds 104!