Why should I get wall insulation?

Up to 35% of the heat can escape through your walls so insulating just the roof and underfloor—and leaving the walls uninsulated— is like going out in cold weather dressed only in your hat and boots.

CosyWall™ insulation was developed to solve this problem by installing wall insulation without having to remove external cladding or internal linings and has been used successfully in thousands of NZ homes since 2002.

With CosyWall Insulation you’ll be cosy all year round—without using any more energy. Typically we can achieve an R-Value of between 2.8 and 3.9, plus CosyWall is higher density than traditional wall insulation batting without the common edge gaps.

What is the CosyWall Insulation System?

The CosyWall process begins with our Licensed installers undertaking a free building assessment. After receiving your written acceptance of our contract, our Licensed installers will retrofit wall insulation through small holes your external cladding or internal linings. As part of this wall insulation process they will also repair any holes or other damage identified during the site assessment. External wall installations are primed and finished with the finish coat you provide, so it’s pretty difficult to spot where we’ve been. For internal installation you’ll have options for rough stop or a ready to paint finish.

CosyWall insulation is a water resistant, non-combustible mineral wool with no added formaldehyde. It is odourless and does not provide food for vermin and it complies with the New Zealand Building Code as a non-hazardous material.

A great investment

External wall insulation is one of the best investments you can make. With external wall insulation you will receive a great return on investment, plus you will receive immediate comfort and satisfaction. External wall insulation is installed once, done right and lasts a lifetime. And the best news is it will reduce your heating bill and has no ongoing costs.

Is Retrofit wall insulation right for my house?

CosyWall is designed to provide effective thermal external wall insulation for older homes with water-tight external timber framed wall cavities (constructed before 1990), with suitably fixed internal linings and external weatherboard, fibre cement, plywood, stucco or brick claddings.


CosyWall™ insulation meets or exceeds NZ Building Code sections B2, E2, E3, F2, H1 requirements when used in buildings at any geographical location in accordance with the manufacturer’s instructions. Our installers can help with any paperwork that your local council may require. And because CosyWall is CodeMark certified your building code compliance is guaranteed.

If you are looking for a green retrofit wall insulation solution then you will be pleased to hear that each bag of CosyWall insulation contains over 45 recycled glass bottles with up to 80% recycled glass content.

Installing retrofit wall insulation will give you a warmer, drier, healthier home – and lower energy bills – so what are you waiting for?