What is the Best Hot Tub Insulation?

One of the main reasons you can stay comfortable in your hot tub during harsh cold weather is insulation. The better the insulation, the less work it is for the hot tub to function.

Less work means less energy spent and a lower energy bill, as well. A hot tub with poor insulation or insulation that isn’t evenly distributed or even of poor quality allows heat to escape.

In order to keep the heat in and the cold out, the floor, the sides, the lid all need to be fully insulated.

Hot Tub Insulation Comparison

There are a few different types of insulation alternatives available for hot tubs. The most common type of insulation you will find is Foam Filled, (filling the entire cabinet full of insulation). Another common method of insulating hot tubs is to spray foam the shell and around the inside perimeter of the cabinet.

Foam Filled

Many hot tub manufacturers are still filling the entire hot tub cabinet full of foam. While they will try to impress upon you that and that filling the cabinet completely full of foam must be better insulation … after all “More is Always Better” right? Not necessarily!
While a foam filled tub is adequately insulated, what they do not account for is the “Law of Diminishing Returns”. Once you have enough insulation to stop the transfer of heat, the insulation value does not get better, it’s just more foam. 3 – 4” of 2lb density foam surpasses the Law of Diminishing Returns to completely stop heat from transferring out of the cabinet.

The Problem With Foam Filled Hot Tubs

There are two main reasons why you shouldn’t buy foam filled tubs;

  1. Access – all of the working parts of your hot tub are submerged in foam, making it very difficult to repair / maintain.
  2. Heat Transfer – most foam filled hot tubs vent the hot air out of the cabinet which is a complete waste of energy.

Perimeter Hot Tub Insulation

At Arctic Spas®, we think about insulating your hot tub just like you like about insulating your home. With Perimeter Insulation, high density polyurethane foam is applied to the cabinet walls and lip underside to a thickness that stops heat loss.

Heat Locking – The Benefit Of Perimeter Insulation

Residual heat from our equipment, primarily our High Flow Energy Efficient motors, is trapped inside the cabinet. By not putting insulation on the shell, we allow for ambient heat from the pump to penetrate the spa shell and heat the water.

By recycling waste heat into the system works better and allows the components to make better use of energy in the system. That also saves energy and money.

This maintains spa water temperature and eliminates many of the heater cycles that other designs, particularly foam-filled insulated designs have to run. Fewer heater cycles mean a lower power bill each and every month.

True Freeze Protection

This heat energy transfer can work in both directions. If you do experience a power outage, Heat Lock will ensure the spa water’s heat will keep the cabinet from freezing.

Our testing indicates that you have about 5 days, at -20ºC before freezing occurs within the cabinet. Giving you peace of mind when you are away from home.

Insulation In The Right Place Saves You Money, Every Day!

When you live in a cold climate, your energy bills are likely already high enough. Why pay more to heat your hot tub every day? With this full hot tub insulation system, more heat is retained, less is used to reheat the tub, and that saves you money.

Energy Efficiency

freeheat cycle

FreeHeat™ Insulation System

The investment in constructing a self-supporting shell allows Arctic ® to insulate differently then the industry standard designed after home construction. We insulate the exterior walls, floor and cover so ambient heat from the pump penetrates the shell and heats the water. This technology offers energy efficiency resulting in lower running costs and true freeze protection.


Forever Floor

Forever Floor

This floor is impervious to moisture, pests and time. All you need is a level surface with no site prep required making installation easy.

Keep The Heat Inside

Cover Mylovac

Mylovac™ Cover

The world’s finest cover is technologically constructed to keep moisture out of your cover inserts. This cover also keeps heat of your tub water in reducing your running costs and are built to last!

You can see how important the insulation is for your hot tub. Strong enough to endure the harshest of winter weather. You know the difference it can make on your home, so why wouldn’t you want that for your hot tub, as well. Contact us for more information on our unique hot tub insulation and product design. Save energy and your energy bill with better insulated hot tubs.