How to Safely Install Insulation Yourself

Thinking of installing insulation yourself? Whether you're tackling a shed, garage, or upgrading your home's thermal performance, installing insulation can be a smart DIY project — but only if it's done safely and correctly.

In this guide, we'll walk you through how to install insulation yourself with safety, comfort, and performance in mind.

1. Choose the Right Insulation Type

Before you begin, it's important to choose insulation suitable for the space. In Perth, our harsh summers and cool winters make thermal performance a priority.

Popular DIY-friendly insulation products:

If you're unsure, read our guide on choosing the best insulation for a shed.

2. Wear the Right Protective Gear

Insulation is safe to install when using the right personal protective equipment (PPE). While Earthwool is softer and low itch, it's still best to wear:

  • Gloves
  • Long-sleeved clothing
  • Safety glasses
  • Dust mask or respirator
  • A cap or hat to protect your head

Tip: Always check the product packaging for specific safety recommendations from the manufacturer.

3. Prep the Area Before You Begin

Clear out the space where insulation will go. This includes removing debris, old insulation (if any), and checking for signs of pests, moisture, or damage.

In a roof cavity:

  • Ensure electrical cables are safely routed and not frayed
  • Avoid stepping directly on ceiling plasterboard – walk on joists only
  • Turn off power to the area if you're unsure of wiring proximity

4. Measure and Cut Correctly

Most Earthwool batts are pre-cut to standard Australian stud spacings (430mm or 580mm wide). Still, you'll need to trim some pieces to fit awkward spaces, corners, or around obstacles.

Use a sharp insulation knife or bread knife with a straight edge for best results.

Do not compress insulation – squashing it reduces its R-value and thermal performance.

5. Install Insulation with Gaps in Mind

The key to effective insulation is full coverage without compression.

For batts:

  • Gently place into wall cavities or between ceiling joists
  • Avoid any gaps between batts or between the batt and the frame
  • Around electrical fittings (like downlights), maintain clearance as per AS/NZS 3000

For foil wrap:

  • Ensure the reflective side faces the correct direction (usually outward)
  • Use approved reflective foil tape to seal joins
  • Maintain the air gap specified by the product to ensure reflectivity works

6. Don’t Cover Ventilation

It's tempting to seal up everything, but your building needs to breathe. Don’t block eave vents, whirlybirds, or any passive ventilation systems.

Check your local requirements for condensation management and air flow (you can find more on this at the National Construction Code).

7. Clean Up Thoroughly

After installation, remove all offcuts, packaging, and stray fibres. Vacuum the area (not sweep), and wash exposed skin with cool water and soap.

Bag up any leftover insulation for future patchwork or use in other areas like sheds or garages.

Can I Install Insulation in Summer?

Yes — but be cautious. Roof cavities in Perth can reach well over 50°C in summer. Always:

  • Work in early morning or late afternoon
  • Take frequent breaks
  • Drink water
  • Let someone know you’re working in the roof

Still Unsure? We Can Help.

Installing insulation yourself can be rewarding and cost-effective — but it’s not for everyone. If you need help choosing the right R-value or batt type, get in touch with our team at Perth Insulation Centre.

We’re Perth’s dedicated Earthwool supplier, offering same-day pickup from Canning Vale and Osborne Park or fast delivery throughout WA.

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