What's Thermolock™ Insulation in Vortex Spas™? (Features, benefits, pros & cons)

Looking to buy a Vortex Spa™ and curious about its insulation? Learn about Thermolock™ Insulation in Vortex Spas™ and why it is vital for spa pools, swim spas, and plunge pools. Explore its features, benefits, and pros & cons.

Insulation plays a vital role in maintaining water temperature and energy efficiency in spa pools, swim spas, plunge pools, and hot tubs.

If you're thinking of buying a Vortex Spa™, this article can be a valuable resource for your research needs, providing insights into the insulation features of Vortex Spas™.

In this article, you’ll learn:

Who is Vortex Spas™?

Vortex Spas™ is a renowned brand known for its high-quality spas, swim spas, and saunas.

As a part of the Jacuzzi Group®, they offer innovative technologies and award-winning designs.

Click below for a detailed review of Vortex Spas™, including the top spa brands in Australia.

Why Insulation is important to spa pools, swim spas, plunge pools, and hot tubs?

Insulation is a critical factor in spa pools, swim spas, plunge pools, and hot tubs for the following reasons:

  • Consistent Water Temperature. Insulation acts as a barrier against external temperature changes, ensuring the water remains consistently warm and comfortable for an enjoyable spa experience.
  • Lower Operating Costs. By minimising heat loss and reducing the energy required to maintain the desired temperature, insulation helps lower operating costs, making it more affordable to own and operate a spa.

What is Thermolock™ Insulation and how does it work?

Heat retention can be achieved through two methods: thermal insulation and radiant barrier.

Thermal insulators are specifically designed materials that minimise the transfer of heat by limiting conduction and convection. Radiant barriers, on the other hand, reflect heat radiation to reduce heat flow from radiant sources.

The Thermolock™ Insulation system combines both methods. It utilises a blanket for thermal insulation and reflective foil for the radiant barrier.

In contrast to the 'foam on shell' insulation method, the Thermolock™ Insulation system effectively retains heat by insulating the inside of the spa's cabinet.

"The better the insulation, the less electricity you will use, therefore the lower the running costs."
Andrew Pullen
Managing Director

This unique approach allows the heat generated by the spa's pumps to be trapped within the insulation system, creating a warm air pocket around the Thermobond™ Spa Shell.

This trapped air, if at a higher temperature than the spa water, will transfer heat back into the water through the shell, resulting in reduced heater usage and cost savings.

In spas with the 'foam on shell' method, however, heat from the pumps is simply wasted and released into the surrounding environment.

What is Thermodynamics?

Here is a simplified explanation of a fundamental principle in Thermodynamics: Heat naturally flows from a hotter object to a cooler object. This principle is key to understanding the Thermolock™ insulation system.

Instead of insulating the spa's shell, the system focuses on insulating the cabinet to trap the heat generated by the pumps around the spa. As the pumps operate, the heat they produce warms the air chamber between the shell and the insulated wall. When the air in the chamber reaches the same temperature as the water, heat loss from the spa water ceases.

To illustrate this principle, consider the difference between cooking a casserole in the oven versus on the stovetop. In an oven, once it reaches the desired temperature, the heating element only turns on when the oven temperature drops below the required level to cook the casserole.

The better the insulation of the oven, the less frequently the heating element needs to turn on. Conversely, when cooking on the stovetop, the heating element must remain on constantly because of the constant heat loss from the casserole to the surrounding environment.

What are the key features of Thermolock™ Insulation in Vortex Spas™?

The following features contribute to the effectiveness of Thermolock™ Insulation in Vortex Spas™:

  • High-Quality Thermal Insulation Material. The insulation system utilises high-quality thermal insulation material that enhances heat retention and prevents energy loss.
  • Multi-Layered Insulation Design. Thermolock™ Insulation consists of multiple layers strategically engineered to minimise heat transfer and maximise energy efficiency. These layers work in synergy to create an effective barrier against heat loss.
  • Structural Reinforcement. The rigid foam layer supports the spa shell, enhancing its durability and longevity.
  • Enhanced Noise Reduction. Thermolock™ acts as a sound barrier, muffling equipment noise and creating a more peaceful spa experience.

What are the pros and cons of Thermolock™ Insulation?

Thermolock™ Insulation offers significant advantages, however, it is important to consider the potential drawbacks of this insulation system. Let’s look at its pros and cons below.


  • Reduced energy consumption and running costs
  • Consistent and longer-lasting warm water
  • Quieter spa operation
  • Enhanced spa shell durability


  • Slightly higher initial cost compared to less insulated spa pools
  • Slightly increases the overall weight of the spa

Watch: What's the best insulation for a spa pool?

Entry Level Vs Mid Level Vs Premium Spa Insulation

If you’ve been checking on your spa options, you may have noticed that there are different insulation options available.

This section differentiates the three main spa insulation levels – Entry Level, Mid Level, and Premium – to help you understand which type best suits your needs.

Entry Level: Foam Sprayed on the Spa's Shell

This type of insulation is typically found in entry-level spas and swim spas, including Fisher™ Spas, and Sun&Soul™ Spas. In this method, a layer of foam is sprayed onto the spa's shell, typically with a thickness of approximately 25mm or 1 inch.

"The perimeter or cabinet Insulation is the absolute minimum standard of insulation you’ll see in a spa."
Andrew Pullen
Managing Director

Pros of Entry-Level Spa Insulation:

  • Budget-friendly
  • Removable, allowing for convenient access to plumbing if needed.

Cons of Entry-Level Spa Insulation:

  • Least effective insulation of the three options.
  • Doesn't insulate the top of the spa, leading to potential heat loss.

Mid-Level: Shell, Base, and Cabinet Insulation

This particular type of insulation, known as Thermolock™ Insulation, is commonly used in mid-level spas and swim spas like Vortex Spas™. It features insulation on the inside of the cabinet, providing insulation for both the water within the shell and the plumbing.

"Not only the spa shell is insulated, but also the base of the spa and probably most effectively is the foam and foil insulation designed to reflect heat loss."
Andrew Pullen
Managing Director

Pros of Mid-Level Spa Insulation:

  • Relatively inexpensive to manufacture, making it accessible for mid-market spas.
  • Insulates both the spa water and plumbing inside the cabinet like full foam.
  • Insulation and cabinet removal provide full access for repairs, reducing repair costs and overall spa ownership costs.
  • Captures heat from running pumps, recycling it to keep the water hot and lowering energy consumption.
  • Helps insulate against pump noise, making spas quieter.

Cons of Mid-Level Spa Insulation:

  • Generally not as effective as full foam, especially in extreme cold climates.
  • High-performance perimeter insulation for cold climates may be less readily available or more expensive.

Premium Level: Full Foam Insulation

Full-foam insulation, also known as “full-fill” insulation is the type of insulation that premium spa brands like Jacuzzi® Spas uses. Full foam insulation insulates the entire area between the outer shell and the inner spa cabinet.

"Except for a small pocket where the controller and pumps are mounted in a Jacuzzi® Spa, the entire gap between the inside of the cabinet and the outside of the shell is filled with foam insulation."
Andrew Pullen
Managing Director

Fully foamed spas and swim spas have foam insulation that not only insulates the water inside the spa shell but also the plumbing and pipe work. This insulation significantly reduces heat loss, making fully foamed spas and swim spas highly efficient and cost-effective to operate.

Pros of Premium Spa Insulation:

  • Insulates both the spa shell and plumbing, resulting in excellent heat retention.
  • Dramatically reduces heat loss, making full foam spas among the most energy-efficient options.

Cons of Premium Spa Insulation:

  • Locating leaks within the waterlogged foam can be challenging.
  • Foam removal and reapplication may be necessary for repairs, leading to potentially higher costs compared to alternative spa insulation types.

Click the button below to learn more about the best spa pool insulation.

In Summary

We hope this article has helped you understand what Thermolock™ Insulation in Vortex Spas™, the different spa insulation options and how they impact energy efficiency, repair costs, and overall ownership experience.

Got questions? If you have any further questions about spa insulation, please click the chat option at the bottom of this page or click the button below to contact us.

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