What does Attic Insulation cost in Australia

Installing insulation in your attic can help improve your home’s energy efficiency and keep temperatures at a comfortable level year-round. But what does attic insulation cost – and is it worth the price?

In this guide, we walk you through the cost of attic insulation, the different types of attic insulation best suited to Australian homes, and how to get the most out of your investment. If you need expert advice about your specific attic insulation project, get in touch with our friendly team at Pricewise Insulation.

Attic insulation vs ceiling insulation vs roof insulation

Attic insulation is used to insulate the attic space, that is the space between your ceiling and roof. While attic insulation isn’t needed in every home, it is essential if you are planning to use your attic as a living space or for storage.

Ceiling insulation is placed between the ceiling rafters (i.e. the attic floor). Ceiling insulation is essential in every home to reduce heat loss and gain, not just if you’re using your attic space for living or storage. The main difference between ceiling and attic insulation is that ceiling insulation sits on top of the ceiling plasterboard whereas attic insulation is installed between the roof joists underneath the roof sarking.

Roof insulation is installed beneath the roofing material. Roof insulation can include products such as reflective foil insulation, roof sarking or blanket insulation.

To work out the cost of ceiling insulation or roof insulation, read our other guides:

What does attic insulation cost?

The average cost to insulate your attic in Australia ranges from $2000 to $3,500. However, prices can vary greatly, depending on how large your attic space is, what type of insulation you use and whether you do it yourself or hire a professional.

Keep in mind the following factors will affect the overall cost of your project:

How much insulation you need or the size of your attic space.
What type of insulation does your attic require? Glasswool batts tend to be cheaper than specialised products such as acoustic insulation and reflective XPS insulation.
What R-Value do you need? R-Value represents the insulating power of the product. The higher the R-Value, the more effective the insulation is at resisting heat flow. Generally, products with a higher R-Value will cost more.
Whether you are installing the insulation yourself or hiring a professional.
How accessible your attic space is. Accessibility to your roof area may affect the installation costs involved. Also, if your ceiling rafters are spaced unevenly this could cause longer installation time and higher costs.

Cost Comparison of Different Types of Attic Insulation

The table below compares the cost per square metre of different attic insulation types.

INSULATION TYPE	AVERAGE COST PER M2*	COST TO INSULATE 150 SQ METRE ATTIC
Glasswool batts (fibreglass insulation)	$9-18	$1,350-2,700
Polyester batts	$15-30	$2,250-4,500
Acoustic insulation	$10-25	$1,500-3,750
Reflective insulation	$12-18	$1,800-2,700
Foam insulation	$10-22	$1,500-3,300

*Costs in this table were last updated December 2022, and pricing is subject to change.

Glasswool Batts

Glasswool insulation, also known as fibreglass insulation, is the most affordable type of attic insulation, costing around $9 -18 per square metre. Glasswool has excellent thermal resistance properties and offers some acoustic properties as well. For better soundproofing, you can upgrade to specially designed acoustic glasswool batts which cost around $10-25 per square metre. Glasswool batts are easy to handle, quick to install and suitable for DIY projects.

Our top picks for insulating your attic with glasswool batts:

Knauf Earthwool Insulation from $9 per m2
Fletcher Pink Batts from $8 per m2
Bradford Gold Hi-Performance Insulation Batts from $17 per m2

Polyester Batts

They are considered a more premium attic insulation material compared to glasswool batts, costing around $8-15 per square metre. Made from recycled plastic materials, polyester batts are non-toxic, non-allergenic and contain no breathable fibres.

For insulating your attic with polyester batts, we recommend:

Bradford Polymax Insulation Batts from $18 per m2

Acoustic Insulation

This insulation will help prevent unwanted noises from travelling from the attic area to the rest of the house and vice versa. It also offers thermal benefits, preventing heat loss and gain. Average costs for attic insulation range from $9-18 per square metre.

The best acoustic insulation products for attics are:

Reflective Foil Insulation

This insulation is designed to reflect radiant heat from the sun away from your home. It comes in thin sheets or is sometimes combined with bulk insulation. A roll of Kingspan AirCell Insulation costs about $12-16 per square metre.

Our most popular reflective insulation products for attics include:

How to work out the cost of insulating your attic

Follow the steps below to work out the cost of insulating your attic space.

Step 1. Select the right insulation product

If you’re not sure what the best kind of insulation for your attic project is, give our team a call at 1300 729 639. Our insulation experts can help you find the right products for maximum performance while staying on budget.

As a rough guide:

In hot climates, reflective insulation is essential to reflect radiant heat from the sun away from your attic space. In most cases, you will need to use reflective insulation in combination with bulk insulation.
Most existing homes already have roof sarking under the roofing material. Attic batts are installed between the joists, ensuring that an air gap is left. Then a product such as Kingspan Insuliner or Insulwhite can be stapled to the rafters to cover the insulation batts.
If you will be leaving your attic insulation exposed, we recommend Kingspan Air-Cell Insulwhite or Kingspan Air-Cell Insuliner.
If soundproofing your attic space is an important factor, consider installing acoustic insulation to prevent noise transfer into and out of your attic. Acoustic insulation can be installed before the attic floor is installed.
Controlling condensation in the attic space is very important, especially for metal roofs. The right attic insulation combined with adequate ventilation can help prevent moisture issues.

Step 2. Choose the right R-Value

The R-Value of an insulation product tells you how effective it is at slowing down heat transfer. The higher the R-Value, the more insulating power the product has. When selecting your attic insulation, you may be subject to local building regulations regarding minimum R-Values, especially if you are planning to use the attic as a livable space.

As a rough guide, we recommend:

R5.0 or higher if you live in Melbourne, Sydney or Adelaide.
R4.0 or higher if you live in Perth, Brisbane or northern NSW.

Step 3. Calculate how much insulation you need

Measure the length and width of the space you need to insulate and multiply these together to get the total m2 required.

If you will be installing batt insulation between timber framing, we recommend multiplying the total m2 by 0.9 to account for the timber framing. This is because you need to allow 10% less for framing per m2.
For foil insulation, we recommend multiplying the total m2 by 1.1 to account for overlapping.

Calculating the total amount of attic insulation needed can be tricky as it depends on the structure of your roof and the existing insulation. To give you a more accurate idea of how much insulation you’ll need, please give us a call at 1300 729 639.

Step 4. Use our attic insulation cost calculator

If you already know how much insulation you need, you can head to our online shop, select the item you want and type in how many square metres you need. Most of our products have an automatic insulation cost calculator underneath for your convenience.

Is Attic Insulation a Good Investment?

If you are planning an attic conversion to use the space for a bedroom, playroom or storage area, it’s crucial to have your attic well insulated. It’ll keep temperatures comfortable for everyone and also protect any materials or objects you keep up there.

Without insulation, your attic space will be uncomfortably hot during summer and uncomfortably cold during winter. This makes it more expensive to keep your space at a comfortable temperature, driving up your energy bills.

Buy Insulation For Your Attic Online With Pricewise Insulation

Looking for high-quality insulation at an affordable price? Pricewise Insulation is Australia’s largest online insulation supplier. Place an order for attic insulation today or give us a call at 1300 729 639 to discuss your project needs and attic insulation costs.