How Much Does Roof Insulation Cost?

Expect to pay between $1,100 to $5,140 for roof insulation cost with an average of 100 square metre roof.

Prices may fluctuate based on the size of your roof, insulation materials to install, job complexities and manner of installation.

Roof insulation is an effective method to prevent heat loss in winter and heat gain in summer. Installing the most suitable type in your roof will help you maximise the benefits of insulation.

Whether you’re improving your home’s thermal performance or investing in new insulation installation, the amount to pay varies depending on your choice of materials and duration of work.

A qualified roof insulation installer can provide quotations based on your exact needs.

Roof Insulation Labour Prices

Installers charge by the hour or per square metre for roof insulation installation projects. The average labour cost to insulate a house can range from $50 to $80 per hour.

The cost of insulation depends on many factors such as the use of special tools and equipment. A professional installer will base their prices on your requirements and how much work is needed.

Always confirm how long it will take to insulate your roof. Installing roof insulation usually takes about 2 to 8 hours depending on the type of the roof and insulation.

What Determines the Cost of Roof Insulation Jobs

Here are various factors that determine how much roof insulation will cost.

1. Accessibility

Gaining access to the roof may incur additional fees to the actual roof insulation. Working at heights or in confined spaces will complicate the process, thus attracting increased costs.

Existing homes have to be thoroughly assessed to locate any obstructions such as electrical wiring and tackle issues before the installation. Hiring a licensed electrician to handle wiring adjustments or electrical repairs will add to your expenses.

2. Roof insulation

The type of roof insulation to install influences how much you will be charged for supplies.

Generally, foil insulation is used in roofs. Also known as reflective insulation, this type is foil faced on one side designed to reflect heat. It is the most affordable among other insulation products.

Insulation batts are also installed as roof sarking. They have varying prices and require a different installation process.

3. Thickness

The thickness of insulation batts determines the roof insulation cost per square metre. Here are a few indicative prices of polystyrene batts based on Rawlinsons’ Australian Construction Handbook 2018, Edition 36.

For expanded polystyrene sheet/batts (Isolite ClassSL) laid in roof space, expect to pay around:

• $10 to $12 per m2 for 25mm thick batts
• $17 to $20 per m2 for 50mm thick batts
• $22 to $ 25 per m2 for 75mm thick batts
• $32 to $ 36 per m2 for 100mm thick batts

The indicative costs of extruded polystyrene tongued and grooved boards laid in roof space are:

• $19 to $23 per m2 for 25mm thick boards
• $28 to $31 per m2 for 30mm thick boards
• $40 to $45 per m2 for 50mm thick boards

Note: Clarify the R-value of the insulation products and determine the level of thickness you will need to suit your property needs. Hire a local roof insulation installer through HIREtrades and ask for recommendations.

4. Replacement

Insulating a new house may cost less than insulating an existing roof. Removing old insulation batts can be time-consuming and labour intensive. However, you have the option to install new layers of insulation on top of the existing batts.

Types of Insulation Applicable to Your Roof

Foil insulation, natural wool and polyester batts are typically installed in roofs.

• Foil or reflective insulation is lightweight and has low thermal conductivity. This type of insulation is used to reflect the sun’s heat.
• Natural wool is a popular roof insulation option for most homeowners.
• Polyester is made from synthetic fibres and works as an alternative choice to glass wool.

Glasswool insulation is often installed in ceiling cavities but can also be used in roofs. This type can either be made from glass fibres or recycled glass bottles. It can be manufactured as loose fill or insulation batts.

Insulation products with high R-values are more reliable in terms of thermal performance.

Get Quotes from Roof Insulation Installer Near You

A clearly defined requirement will help your roof insulation installer to figure out appropriate solutions in meeting your needs. Before hiring, ensure that you obtain prices from several contractors and compare them.

Most states across Australia do not require installers to be licensed. In South Australia, however, it is mandatory. Always look for experienced installers to handle your insulation project and meet your roofing needs.

Insulating your roof is one of the best energy-saving solutions that many homeowners invest in. Along with ceiling insulation, you can save up to 45 per cent on heating and cooling energy.

Hiring an experienced roof insulation installer will help to keep your property well-insulated.

Post your roof insulation installation job now and get quoted by up to three local installers.