What is ThermoWall?

ThermoWall is a liquid foam with the consistency of shaving cream. ThermoWall is an insulating plastic foam containing millions of tiny air cells. When injected into a wall cavity it flows around the timber framing filling the cavity to form a thermal barrier. 
It is non toxic, does not create a fire hazard, and is a breathable, water repellant foam.


What does it do?

By creating a thermal barrier, ThermoWall keeps heat in during winter and the heat out during summer creating a comfortable, healthy and energy efficient environment.


Thermal Insulation

Resistant to heat and cold, ThermoWall has a high R-value compared to most wall insulation materials when laboratory tested. Because ThermoWall ‘flows’ around obstacles within the wall cavity, it achieves a very high fill ratio of the cavity. 

This reduces air penetration into the home, particularly on older structures without building paper, through gaps in the wall linings and external cladding. This air infiltration is a large portion of the building heat loss.


Sound Insulation

ThermoWall reduces noise penetration into the home. It can also be used for internal walls.


Fire Performance

ThermoWall is non-flammable It will char, lose weight and volume, but will not add fuel to a fire.



Some initial shrinkage will occur, during the curing stage, but ThermoWall will not slump or sag within a wall cavity. ThermoWall contains mould inhibitors and will not support the growth of mould.


15 Year Guarantee

ThermoWall customers receive a 15 year guarantee which covers the product material and installers workmanship. In the unlikely event that the ThermoWall installed in your house is proven to be be defective or deteriorates then HeatSavers will reinstall ThermoWall into the areas of the house which are affected, or are defective.

While we offer a 15 Year Guarantee, if undisturbed, ThermoWall should keep your home warmer, drier and healthier for many more years, as it has already for thousands of New Zealand homes for over 30 years.


Non-expanding modified plastic foam.


ThermoWall is the only product designed specifically for retro-fitting into the walls of homes built pre-1991. 
ThermoWall is only installed by licensed, certified installers 
using patented computerised equipment to ensure consistent foam quality.


ThermoWall installers are available nationwide. ThermoWall is a very cost-effective option for retro-fitting into walls.