Australia has a major insulation issue, and it is particularly problematic for homes built more than 15 years ago. According to 2024 research from Core Logic, the median energy efficiency rating for homes built before 2010 was just 2.8 stars out of 10 (ABC News Australia). As a result, many Australians find themselves freezing during winter and boiling during summer.
When we talk about insulation, the roof is one of the most important areas to consider, particularly in homes with Colorbond steel roofing. Putting the right insulation beneath the roof can help to reduce heat transfer, as well keep your property more comfortable throughout the year.
If you’ve been looking into insulation for a Colorbond roof, chances are you’ve come across terms like Anticon, sarking and roofing blanket. But what’s the difference between them? Is one better than the others, and which option is right for your roof?
Let’s take a closer look.
The Benefits of Roof Insulation
The Australian climate is harsh and things are only getting more unpredictable. Luckily, the right roof insulation helps to manage everything from the height of summer to the depths of winter.
Here are the most notable benefits:
1. Keeping Your Home Cooler in Summer
Anyone with an uninsulated home knows just how hot it can get on a sunny day. This is because insulation helps to reduce the amount of that heat that makes its way through the roof and into your home.
The right measures, whether that’s anticon or sarking, will make a noticeable difference during Melbourne’s hotter months, particularly in rooms directly beneath the roof.
2. Staying Warmer During Winter
Insulation works both ways. During winter, it helps slow the loss of warmth through the roof.
That means the heat you’re paying to produce stays inside for longer, rather than escaping through the roof space.
Source: YourHome.gov.au
3. Reducing External Noise
Rain on a steel roof can be loud, especially during a heavy downpour.
Roofing blankets such as Anticon can help absorb some of this sound, making the noise of rain less noticeable inside the home.
4. Helping to Manage Condensation
Condensation is another consideration with steel roofing.
Warm, moist air inside the building can come into contact with cooler surfaces in the roof space, creating moisture. The right roofing products can help manage this moisture and reduce the risk of problems developing over time.
Sarking has an important role here, as it provides a protective membrane beneath the roof sheets. (Roofing Options)
5. Making Your Heating and Cooling More Effective
A well-insulated roof makes it easier to maintain a comfortable temperature inside your home.
Your heating and cooling systems don’t have to work as hard to counteract heat entering or escaping through the roof. That can mean a more comfortable home and potentially lower energy use.
The key thing to remember is that different roofing products do different jobs. This brings us to Anticon and sarking, which are often mentioned together when you’re looking at insulation for a Colorbond roof.
What Is Anticon?
Anticon is a foil-faced roofing blanket designed for use beneath metal roofing. It combines bulk insulation with a reflective foil facing, giving it two different ways of helping with heat transfer.
The bulk insulation helps to slow conductive heat transfer, while the reflective foil helps reflect radiant heat. This makes Anticon a popular choice beneath steel roofing.
It can also provide some acoustic benefits by helping to reduce the noise associated with rain hitting metal roofing.
The main things to know about Anticon are:
- It contains bulk insulation.
- It has a reflective foil facing.
- It is designed for installation beneath metal roofing.
- It can help with thermal performance.
- It can provide some noise reduction.
- It can assist with condensation management when correctly installed.
What Is Sarking?
Sarking is a thin membrane installed underneath the roof sheets and above the roof frame. It does not contain the same type of bulk insulation found in a roofing blanket such as Anticon.
Often referred to as reflective foil laminate or sisalation, roof sarking is typically made from a combination of aluminium foil and durable backing materials designed to resist moisture, improve insulation, and provide additional weather protection.
Depending on the product, sarking can help with:
- Moisture and condensation management
- Wind-driven rain
- Dust
- Radiant heat
- Ember protection in applications where an appropriate BAL-rated product is required
What’s the Difference Between the Two?
Anticon and sarking are both used beneath steel roofing, but they have different roles within the roof system.
Anticon is a type of roofing blanket, combining bulk insulation with a reflective foil facing. The insulation helps slow heat transfer, while the foil provides a reflective surface that can help with radiant heat.
Sarking is a roofing membrane installed beneath the roof sheets. Depending on the product, it can help manage condensation and moisture, provide a secondary barrier beneath the roof and reflect radiant heat.
That doesn’t make one better than the other. They are simply designed to do different jobs.
What About Blanket Insulation?
Blanket insulation is another option you’ll often come across when looking at insulation for a steel roof. Unlike sarking, which is a membrane, blanket insulation contains a layer of bulk insulation that helps slow the transfer of heat through the roof.
It can be installed beneath Colorbond and other steel roofing and can help with:
- Keeping your home cooler in summer
- Retaining warmth during winter
- Reducing the sound of rain on the roof
- Improving the overall thermal performance of your roof
Anticon is one example of a foil-faced roofing blanket, combining bulk insulation with a reflective foil layer.
The Role of Roof Sarking in Metal Roofing
Sarking is a great addition to a steel roofing system, particularly with Colorbond roofing. Installed beneath the metal sheets, it adds an extra layer between the roof and the roof space, helping the roof perform better in changing weather conditions.
In the case of steel roofing, sarking works as part of the complete roof system alongside the roof sheets, insulation and ventilation. It also helps to provide an extra layer of protection beneath the Colorbond sheets, all while contributing to a more comfortable roof space.
Find a Great Range of Colorbond Supplies at Roofing Options
Whether you’re building, renovating, or planning a large-scale commercial development, Roofing Options is the number one destination for high-quality COLORBOND® roofing supplies in Melbourne.
We supply high-quality Colorbond roofing supplies, sheets, panels, custom flashing, downpipes, and a full range of DIY kits. Our staff have an in-depth knowledge of roofing materials and only supply products from trusted brands and manufacturers. This includes season-proof products designed to suit all weather conditions.
Get in touch with Roofing Options today to learn more about roof sarking, Velux skylights, quality guttering, or premium COLORBOND® roofing solutions.
Order online or give us a call on 03 8339 1150 (Campbellfield) or 03 9702 3301 (Clyde North) and our expert team will help you find the perfect product.
Frequently Asked Questions
What is the difference between Anticon and sarking?
Anticon is a foil-faced roofing blanket containing bulk insulation, while sarking is a membrane installed beneath the roof sheets. Anticon is primarily used to help with thermal insulation, while sarking can provide a protective layer that helps manage moisture, condensation, radiant heat and wind-driven rain.
Is sarking enough insulation for a Colorbond roof?
Sarking can contribute to the thermal performance of a Colorbond roof, particularly when using a reflective foil product, but it does not provide bulk insulation in the same way as a roofing blanket. The right setup depends on the level of insulation your roof requires and how the rest of the roof system is designed.
What does Anticon do under a metal roof?
Anticon sits directly beneath the metal roof sheets and combines bulk insulation with reflective foil. The bulk insulation helps slow heat transfer, while the foil helps reflect radiant heat. It can also help reduce some of the noise created by rain hitting a steel roof.
Can you use sarking and blanket insulation together?
Sarking and blanket insulation can form part of the same roofing system because they serve different purposes. Sarking provides a protective membrane beneath the roof sheets, while blanket insulation provides bulk insulation. The combination used will depend on the roof design and the requirements of the property.
Does roof insulation help with condensation on a steel roof?
The right roofing products can help manage condensation, but insulation alone isn’t the whole solution. Sarking can provide an additional layer beneath steel roof sheets to help manage moisture, while appropriate ventilation also plays an important part in managing conditions within the roof space.
