If you’re upgrading to a metal roof in South Australia, adding a roof blanket can bring about many years of comfort. It essentially insulates your home from the outside elements, improving energy efficiency, reducing condensation, cutting down rain noise, and extending the life of your roofing insulation system.
At Roof & Render SA, we’ve been replacing roofs for over 100 years. From asbestos and tile to full Colorbond® transformations, our team has seen how the right insulation blanket can significantly improve both performance and livability.
In this article, we will look into the real, practical benefits of installing a roof blanket under your Colorbond® metal roof, and why thousands of South Australian homeowners trust us to get it done right.
A roof blanket is a dual-layer insulation solution that sits directly under your metal roof, between the roof sheets and battens. It’s made of bulk insulation (commonly spun from molten glass into a fine wool known as glasswool) and a reflective foil facing.
• The bulk insulation layer traps air, slowing heat transfer.
• The reflective foil bounces back radiant heat, preventing it from entering your roof cavity.
It provides a high-performance roofing insulation system that works year-round (summer and winter) to keep your home more comfortable and energy efficient.
Properly installed roof blankets deliver powerful benefits across energy savings, moisture management, noise reduction, and climate comfort. Let’s break that down.
By reducing heat transfer through the roof sheets, a roof blanket insulation system helps stabilise indoor temperatures, keeping hot air out in summer and warm air in during winter. According to the Australian Government’s YourHome guide, adding ceiling or roofing insulation can cut heating and cooling costs by up to 45%.
That’s a serious saving on your energy bills, especially in areas like South Australia where temperature fluctuations can be intense.
Here’s something many people overlook: metal roofs can build up condensation on the underside when warm indoor air rises and meets the cooler roof surface. That moisture, over time, can lead to:
• Timber rot
• Rust and corrosion on roof sheets
• Mould growth in your ceiling or roof space
A high-quality roof blanket acts as a moisture control barrier, thanks to its anti-condensation function. It blocks moisture-laden air from condensing on cold surfaces. This feature is essential for skillion roofs or homes with low ventilation, which are common in South Australia.
Do you live under a flight path? On a main road? Do you hate the sound of heavy rain on your roof?
A roofing insulation blanket doesn’t just keep your home warmer. It helps quieten it too.
The bulk insulation absorbs unwanted noise from outside. The reflective foil helps reduce reverberant noise inside the roof space. Together, they can reduce indoor noise by up to 12–15 decibels – a difference you’ll notice instantly, particularly with metal roofing.
Whether it’s aircraft noise, traffic, or the pelting of rain, the right insulation blanket can improve your home’s acoustic performance significantly.
At Roof and Render, our roof blankets are made of glasswool blanket products that meet or exceed Australian Standards (AS/NZS 4859.1) for:
• Fire resistance
• Thermal performance
• Long-term durability
Additionally, the quality roof blanket materials we use often contain recycled content and have zero or very low ozone-depleting potential, making them an eco-conscious option as well.
And yes, we install high-grade roofing blanket insulation as an optional extra with every roof replacement, never as a standalone service.
Reducing greenhouse gas emissions starts at home. With better energy efficiency, you’ll rely less on air con and heating, both of which are energy-intensive.
Most insulation blankets we install are made using recycled materials and thermosetting resin, a binder that keeps them stable and safe over time. That’s a great win for both performance and the planet.
We often get asked if roof blanket installation is suitable for South Australian homes. The answer? Absolutely.
South Australia’s hot, dry climate combined with increasingly unpredictable weather events means your roofing system needs to work harder. A roof blanket not only improves thermal performance, but also helps extend the life of your metal roofing by protecting it from internal corrosion caused by condensation.
Plus, most roof blanket insulation installation products available today meet or exceed Australian Standards for fire safety, environmental impact, and performance longevity.
A roof blanket is best installed during a roof replacement, before the new Colorbond® sheets go on. That’s why we only offer it as part of our complete re-roofing projects, not as a patchwork job.
We remove old tile, asbestos, or aged metal roofs, and replace them with modern Colorbond® roofing systems, fully sealed with a roofing blanket insulation layer and optional solar vents for added airflow.
Want to see how it works? Visit our interactive showroom at 2/22 O’Sullivan Beach Rd, Lonsdale or check out our Colorbond® display centre at the Building Ideas Centre in Adelaide.
While standard ceiling batt insulation (like polyester or fibreglass) helps slow heat transfer, it doesn’t offer the same all-round protection as a roof blanket. Below is a side-by-side comparison highlighting the differences in thermal performance, condensation control, and long-term benefits.
Benefit | Roof Blanket | Ceiling batt Insulation |
Thermal insulation | Excellent. Combines bulk insulation with reflective foil to block radiant heat | Good. Slows heat flow but doesn’t reflect radiant heat |
Moisture control | Very effective. Anti-condensation function manages internal moisture and vapour | Limited. No built-in vapour barrier or foil facing |
Noise reduction | Reduces indoor noise by up to 12–15 dB, especially on metal roofs | Limited. Standard ceiling batts (like polyester or fibreglass) offer basic sound absorption but lack the density and coverage needed to reduce external noise |
Fire resistance | Meets or exceeds Australian fire safety standards (AS/NZS 4859.1) | Fire-rated, but performance varies across brands |
Energy cost savings | Can cut heating/cooling costs by up to 45% | Reduces energy use, but is less effective in hot metal roof applications |
Environmental impact | Often made with recycled glasswool, low ozone-depleting potential | Varies. Many options use synthetic materials with higher emissions |
Are you ready to replace your old tile or metal roof with a premium Colorbond® roofing system, complete with insulation? Request a consultation, site inspection or quote by getting in touch with us today for a tailored, obligation-free consultation. Prefer to visit us in person? Book a showroom consultation at our Lonsdale or Adelaide office to explore your roof insulation options firsthand.
If the roof blanket becomes wet during installation and isn’t dried out, it may temporarily lose some of its insulating performance. However, most modern glasswool blankets are moisture-resistant and will dry naturally over time without damage.
Yes, particularly for Colorbond® roofs, where reflective foil enhances thermal efficiency and protects against condensation control issues under large surface areas.
The R-value (a measure of thermal resistance) varies depending on thickness and material. Most roof blankets used in Australia range between R1.3 to R2.5.² Keep in mind that combining it with ceiling insulation can significantly improve overall performance.
The reflective foil layer should typically face down toward the ceiling cavity to reflect radiant heat. However, installation may vary depending on roof design and ventilation requirements. Always follow the manufacturer’s guidelines or ask your roofing specialist.
With professional installation and minimal disturbance, a quality roof insulation blanket can last over 25 years, often matching or outlasting the lifespan of your metal roofing itself.
Yes! Roof blanket insulation installation can be performed during re-roofing or renovation projects. It’s an ideal opportunity to add insulation, especially if you’re upgrading to Colorbond®. That’s why we only offer it as an add-on during a re-roofing project, not as a standalone service.
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We will give you a call within 24 hours to organise a time that suits you.
