How to Insulate Your Walls Without Removing the Plasterboard

Many homes in New Zealand were built before wall insulation became standard. As a result, they often have no insulation in the walls at all. This makes homes harder to heat in winter and keep cool in summer. Even if you have ceiling and underfloor insulation, your home can still lose a lot of heat through uninsulated walls. 

Adding insulation to existing walls used to mean removing the plasterboard, which is messy and expensive. Now there is a better option. With CosyWall Insulation, you can insulate your walls without removing the plasterboard. 

Why uninsulated walls are a problem 

Walls take up a large part of your home’s surface area. If there’s no insulation inside them, heat can pass through quickly. In winter, warm air escapes and cold air gets in. In summer, heat builds up inside, especially when the sun hits the outside walls. These temperature changes means your heating or cooling system has to work harder. This leads to higher power bills and more energy use. Insulating your walls helps trap heat where you want it, making your home more comfortable and efficient all year. 

How We Insulate Your Walls Without Removing the Plasterboard 

CosyWall is a blown wall insulation system designed for retrofitting insulation into older homes. This method lets us install insulation from the inside or outside, directly into the wall cavity, without the need to remove internal linings or external cladding. 

Installation process  

STEP 1 – Assessment 

First, our team visits your home to assess the condition of your walls. We check for things like power points, pipes, and framing. We also look at the type of wall lining and the space inside the cavity to make sure it’s suitable for our system. 

STEP 2 – Drilling access holes 

Once the walls are cleared for insulation, we drill small holes through the plasterboard or external cladding. These are placed in a way that allows us to fill the entire cavity evenly. Installers carefully space the holes to reach all parts of the wall.

STEP 3 – Installing the insulation 

Using specialised equipment, we then blow CosyWall Insulation into the walls of your home. Installers blow CosyWall in at such a high density that it won’t shrink or slump inside your walls.
It creates a full thermal barrier, sealing the wall cavity and reducing draughts and heat loss. 

STEP 4 – Sealing the wall 

Once CosyWall has been blown into your walls, we will go around and seal all the holes with a special compound that ensures your house remains weathertight.                                   

Why Choose CosyWall for Your Wall Insulation 

CosyWall gives homes the wall insulation they need without the hassle of removing plasterboard or cladding.

Our system is: 

Less invasive – No need to strip walls or take down gib 

Fast and tidy – Most installations take just one day 

Proven – We’ve insulated thousands of New Zealand homes 

CodeMark certified – Meets New Zealand building standards 

We work with homeowners across the country to make homes warmer, drier, and more energy-efficient. Our trained installers follow a tested process that gives consistent results with minimal disruption. 

Better Comfort with Less Energy Use 

You’ll notice the difference once insulation goes into your walls. Rooms stay warmer for longer and don’t heat up as much in summer. This means your heat pump or heater doesn’t have to run as often. You’ll use less power and enjoy a more stable indoor temperature. Wall insulation also helps reduce noise from outside, giving you a quieter home.  

Insulate Your Walls with CosyWall 

If you’re unsure whether your home has wall insulation, we can check for you. We offer free insulation assessments and can let you know if wall insulation is needed. Get in contact with our team today and find out how CosyWall can make a difference in your home. 

See how we handle external wall insulation.