How Insulation Relieves Hot Houses in Perth and WA Summers

Summer in Perth and across Western Australia can be brutally hot, with daytime temperatures regularly soaring above 35°C. For many homeowners, keeping indoor spaces cool becomes a daily battle — especially in homes without effective insulation.

In this guide, we explore how insulation works to relieve heat in homes, what products are best for Perth’s climate, and how to upgrade your property with the right thermal protection.

Why Is Your House So Hot in Summer?

Uninsulated or poorly insulated homes suffer from heat gain, where external heat enters through the roof, walls, and windows, making your air conditioner work harder (and costing you more in electricity).

Common causes of excessive summer heat indoors include:

  • Uninsulated roof spaces and ceiling cavities
  • Direct sunlight on north- and west-facing walls
  • Lack of reflective barriers in sheds or metal-framed buildings
  • Heat transfer through brick veneer without cavity insulation

How Insulation Keeps Your Home Cooler

Insulation acts as a barrier to heat flow. In summer, it slows the entry of radiant heat from outside, helping your home stay cooler for longer and reducing reliance on air conditioning.

Types of insulation that help reduce summer heat:

Best Insulation Products for WA Summers

At Perth Insulation Centre, we recommend Earthwool and Trade Select products for homeowners looking to beat the heat affordably and effectively.

Learn more about choosing the right R-value for your home.

Insulating Sheds and Outbuildings

Hot sheds and workshops are a common complaint across WA. Insulating them with foil and batts can make a massive difference, turning them into usable spaces year-round.

Read our full guide on the best insulation for sheds in Perth.

Does Insulation Work Without Air Conditioning?

Absolutely. Insulation helps maintain a stable indoor temperature, meaning your home stays cooler for longer — even without running an air conditioner 24/7.

In fact, with good insulation and passive cooling design, many Perth homes can significantly reduce cooling costs and energy consumption.

Where to Buy Summer-Ready Insulation in Perth

Perth Insulation Centre is your local supplier for:

  • Earthwool wall and ceiling batts
  • Trade Select foil wraps and thermal breaks
  • Wall wraps and builders foil
  • Same-day pickup from Canning Vale and Osborne Park
  • Fast delivery across Western Australia

Need help selecting the right product? Contact our team today.


Further Reading:

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