Can You Add Insulation to Existing Walls? Here’s How It’s Done

10 November 2025

Many Melbourne homeowners ask, “Can you insulate walls without tearing them down?” The good news is yes, you can! With modern retrofit wall insulation techniques, you can make your home warmer, quieter, and more energy efficient all without major renovations.

Why Insulate Existing Walls?

If your home was built decades ago, chances are the walls have little to no insulation. Uninsulated walls can let up to 25% of your heating and cooling energy escape, making rooms harder to heat in winter and cool in summer.

Adding wall insulation provides major benefits:

Reduces heat loss and cuts energy costs
Keeps your home comfortable all year round
Minimises noise between rooms and from outside
Reduces condensation, damp, and mould growth

For Melbourne’s variable climate,upgrading your wall insulation is one of the smartest energy-saving improvements you can make and the best returns on investment.

Methods for Adding Insulation to Existing Walls

There’s no need to strip your home back to bare studs. Depending on your wall type and and renovation plans, you can choose from several proven retrofit wall insulation methods:

Blow-In Insulation

A fast and non-invasive method ideal for cavity wall insulation. Small holes are drilled into the wall and loose-fill insulation (like glasswool or cellulose) is blown into the cavity. It’s efficient, clean, causes minimal disruption and perfect for older brick homes in Melbourne.

Internal Wall Insulation

If you’re renovating an interior space, internal wall insulation batts or rigid panels can be installed between timber studs before plasterboard is replaced. This method is great for improving both thermal comfort and acoustic control inside your home.

External Wall Insulation

During major renovations or recladding, external wall insulation can be added as an outer layer, creating a continuous thermal barrier. This approach maximises energy efficiency and protects against weather exposure.

🔧 Choosing the Right Insulation Material

The best insulation depends on your wall type, climate, and energy goals. At OZ Homes Insulation, we stock a wide range of wall insulation products to suit any retrofit project, including:

Polyester wall insulation – non-irritant, durable, and sustainable
Earthwool / Glasswool batts – popular for their high thermal and acoustic performance
Reflective foil insulation – adds radiant heat protection, ideal for warmer conditions

Explore our full range of wall insulation products to find the perfect solution for your home.

Professional vs DIY Installation

Some small retrofits or accessible wall sections can be insulated as a DIY project, especially using pre-cut batts. However, for complete wall coverage or cavity installations, professional installation ensures correct fitment, safety, and compliance with Australian energy standards.

Professionals use the right tools to assess wall cavities and materials to install wall insulation with minimal damage to existing finishes to achieve safe, high-quality results that perform long-term saving you money and energy for years to come.

Why Buy from OZ Homes Insulation

OZ Homes Insulation is Melbourne’s trusted source for premium, eco-friendly insulation. We supply top-rated brands offering:

High R-values for superior performance
Environmentally responsible materials
Competitive prices and Melbourne-wide delivery
Friendly expert advice to help you choose the right product

Whether you’re tackling a small DIY project or a full home retrofit, we provide wide range of products with expert advice and Melbourne-wide delivery to make your insulation upgrade simple and effective.