Explore the benefits, materials, and installation methods of underfloor insulation to keep your home warmer in winter, cooler in summer, and more energy-efficient all year round.
Why Underfloor Insulation Matters
Up to 20% of a home’s heat loss can occur through uninsulated floors. Underfloor insulation enhances comfort, improves energy efficiency, and boosts indoor air quality—especially in older homes with timber floors or raised foundations.
Key Benefits of Underfloor Insulation
- Temperature Stability: Prevents cold air in winter and reduces heat gain in summer.
- Energy Savings: Cuts heating and cooling costs by 10–20% when combined with wall and ceiling insulation.
- Moisture Protection: Reduces condensation and mould risk.
- Noise Reduction: Minimises footstep noise and external sounds in multi-storey homes.
- Comfort: Eliminates icy floors on cold mornings.
Types of Underfloor Insulation
- Polyester or Glasswool Batts: Safe, non-toxic, and easy to install for timber floors with crawl spaces.
- Reflective Foil Insulation: Reflects radiant heat, ideal for hot climates.
- Rigid Foam Boards: High R-values, suitable for concrete slabs or under tiles.
- Spray Foam Insulation: Expands to fill gaps, providing both insulation and air sealing.
Best Installation Methods
- Timber Floors: Batts or foil fitted snugly between joists, secured with strapping or mesh.
- Concrete Slabs: Rigid boards or spray foam applied before flooring; retrofits may use panels or thermal underlay.
Energy Performance – Understanding R-Values
- Hot Climates: R1.5 – R2.0 (reflective solutions preferred)
- Temperate Climates: R2.0 – R2.5
- Cold Climates: R2.5 – R3.5+
DIY vs Professional Installation
DIY is possible for timber floors with crawl spaces but can be dusty and tricky. Professionals ensure correct fitment, compliance with Australian standards, and safe material handling.
Costs and Return on Investment
Typical costs range from $30 to $55 per m², depending on material and installation complexity. Most homeowners recoup the cost within 4–6 years through energy savings.
Signs You Need Underfloor Insulation
- Icy floors in winter despite heating.
- Unusually high energy bills.
- Drafts near skirting boards.
- Condensation or dampness under the home.
Final Thought
Underfloor insulation is a highly effective upgrade for Australian homes. It reduces drafts, stabilises temperatures, and lowers energy bills, offering comfort and long-term savings.
“Explore the benefits, materials, and installation methods of underfloor insulation to keep your home warmer in winter, cooler in summer, and more energy-efficient all year round.”
