There are many reasons to insulate water pipes in your home; one is to decrease the odds of them freezing.

Why insulate pipes?    

The primary function of insulation is to reduce the heat transfer in a system. If you have had a problem with pipes freezing anywhere in your home, adding insulation helps maintain the temperature of the fluid in the pipe above the freezing point. However, freezing is not the only issue. Especially in the summer months, in unconditioned spaces, insulating will help keep that cold tap water cold. Insulation can also add protection against condensation, especially in high-humidity environments. A buildup of condensation can accumulate in these out-of-the-way spots which could go undetected over time, leading to extensive water damage just like a frozen pipe busting.

What’s a good insulation to use?

Any material that has low thermal conductivity will perform well as an insulator.. Foam insulation, unlike fiberglass, is a closed-cell structure that acts as a built-in vapor retarder (jacket) preventing moisture intrusion. Closed-cell  insulation products like ArmaFlex, Tundra and Tubolit prevent condensation, moisture intrusion and loss of thermal efficiency.  These products are flexible and easy to work with in tight spaces.  They are also fiber-free and won’t cause the discomfort of fiberglass insulation. ArmaFlex is ideal for applications operating in frigid climates because it remains flexible down to -40°F and its excellent thermal conductivity and low water vapor permeability make it extremely efficient at preventing condensation.

Armacell’s two popular insulation types:

  • ArmaFlex® the original, elastomeric (rubber) flexible closed-cell pipe foam pipe insulation for HVAC, refrigeration and plumbing.
  • Tundra® and Tubolit® economical polyethylene (PE) flexible closed-cell pipe foam insulation for residential heating and plumbing lines.

How much insulation is required to prevent heat loss?

Choosing the correct insulation thickness is crucial in slowing heat transfer to achieve long-term thermal and condensation control, even under extreme conditions. As the insulating thickness is increased, the prevention of heat loss levels off very quickly. Any additional insulation will result in diminishing return of heat loss prevention and costs. Over 70% of energy conservation can be achieved by the first half inch of insulation. We recommend ½” insulation on most residential piping.

Where to insulate? 

Every section of water pipe in your home can benefit from insulation, but in some cases, it can be impossible to install if the walls have been sealed up. There are areas in your home that should be accessible that will definitely benefit from insulation. The best places to start are water pipe runs in any unconditioned spaces like a crawl space, garage, utility room, or basement with exposed piping. It is important to cover all exposed piping surfaces including valves and faucets with insulation. 

Where can I buy pipe insulation? 

Hardware retailers like Ace Hardware, Menard’s, Do-It-Best and The Home Depot offer Armacell’s pipe insulation as well as recommended accessories. You can find both a selection of polyethylene and rubber foam insulation to meet the specific needs of your project. Common pipe sizes are offered in stores while additional sizes and products such as continuous coils / cartons are made available to order online at and soon to be available on Keep in mind selecting the right accessories plays a critical role in installation and assures performance.


During normal operation, the temperature of a domestic hot water system will never get above 180°F and all Armacell insulation products may be safely installed on systems operating up to 180°F. When insulating near a hot water heater, especially natural gas hot water heaters, follow the manufacturer’s recommended guidelines to reduce potential fire hazards.