In this guide to the best roof insulation in Australia, you’ll find out what type of insulation you need, what R-Value is ideal and where to buy high quality, affordable insulation online.
Bulk Vs Reflective Insulation – Which One Do You Need?
There are two main categories of roof insulation; bulk and reflective insulation. Bulk insulation has millions of tiny air pockets and works by trapping air within its structure. Bulk insulation cannot be compressed as this will reduce its air pockets and compromise its insulating ability. This insulation works by reducing the conduction of heat flow between objects that are adjacent to each other.
On the other hand, reflective insulation primarily affects radiation heat flow. It usually consists of a foil layer backed by a paper or plastic layer. Reflective foil needs to be kept clean for it to work properly, and the reflective side must be faced downwards. More recently, roof insulation has been designed to incorporate both bulk and reflective insulation for highest performance and insulating capabilities.
What Is The Best Insulation Material For Roofs?
Roof insulation is made from a number of different materials, depending on whether it is bulk and/or reflective insulation. The most common bulk insulation materials used are glasswool, and polyester.
At Pricewise Insulation we have a variety of glasswool and polyester roof insulation products to suit many home styles and desired thermal performance.
Glasswool Bulk Insulation
Glasswool insulation is made from recycled glass materials and is the most common insulation material used in both residential and commercial buildings. Although glasswool has a stigma of being itchy and uncomfortable to install, recent technological advances have improved this and today many glass wool insulation products claim to be low-itch or itch free.
Polyester Bulk Insulation
Polyester insulation is manufactured from recycled PET plastics such as drink bottles. Polyester insulation is bonded together by heat and no binder chemicals are added. This gives polyester its rigid, flexible and hypoallergenic structure.
Foil Reflective Insulation
Foil insulation has a reflective surface which creates a radiant barrier against heat transfer from the sun. It is important that foil insulation is installed correctly to ensure its full insulating capabilities are reached. The R-Value of reflective foil insulation will depend on how it is installed and what climate you are living in.
Best Roof Insulation Brands In Australia
The top glasswool roof insulation products include:
- Knauf Earthwool Ceiling Batts
- Pink Batts Glasswool Ceiling Insulation
- Bradford Hi-Performance Gold Ceiling Batts
- Bradford Black Hypoallergenic Ceiling
The best polyester roof insulation products include:
- Bradford Polymax Thermal Ceiling Insulation Batts
- Greenstuf Polyester Ceiling Insulation (only available in VIC)
Roof foil insulation products available at Pricewise insulation include:
- Kingspan Air-Cell Insulbreak 70
- Sisalation Metal Roof Sarking
The following products combine both bulk and reflective insulation:
- Knauf Earthwool Roofing Blanket Roll with Foil Facing
- Fletcher Permastop Building Blanket Insulation
- Bradford Anticon Roofing Blanket
For more information, check out our brand comparison of the best ceiling insulation products in Australia.
Should I Buy Roof Insulation Batts Or Rolls?
This depends entirely on your own personal preference as functionally. Both these forms of bulk insulation are equally effective at insulating. The main difference is the way in which they are installed.
Roll insulation can be ‘rolled’ out between the ceiling joists without needing to be cut into segments. This is especially useful for ceiling spaces that have few obstacles and a large space to work in (which are generally few and far between!).
However, if you have many obstacles and a small ceiling space area, insulation batts may be a more appropriate option. As batts are pre-cut, they are easy to install and cut to fit any space.
Are You Retrofitting Ceiling Insulation Or Installing During A New Build?
Insulation installers can install ceiling insulation in both new and existing homes. In some cases it may be possible to install new insulation over old insulation to boost the overall R-Value. If the old insulation is damaged, mouldy or infested it should be completely removed before the new insulation is installed.
Pitched Roof With A Flat Ceiling
For pitched roofs with a flat ceiling where there is crawl space, it may be possible to install insulation from inside the ceiling space. We recommend installing insulation batts in between the ceiling joists as well as installing sarking or foil batts beneath the roof to help with radiant heat.
Roofs With No Crawl Space
For roofs with no crawl space, for example if you are lifting a metal roof to install insulation, we recommend putting down insulation batts first on top of the plaster. Then we suggest putting down some sarking or Kingspan Air-Cell Insulation with the silver side up to reflect radiant heat away from the house.
For tailored advice about the best roof insulation for your project, give our insulation specialists a call and we’d be happy to talk you through your options.
What Is A Good R-value For Roof Insulation?
To answer the question “What is the most effective roof insulation?”, the most important factor you should consider is the R-Value of the insulation product. The R-Value indicates how effective it is at preventing heat loss and heat gain. The higher the R-Value, the more effective the insulation product is, and the more potential savings you can make on your energy bills.
The roof is responsible for the greatest heat loss and heat gain in a home – as much as 35%! Choosing the right R-Value for roof insulation is very important to ensure your home can regulate temperatures well all year round. There are guidelines in the Building Code of Australia outlining the minimum R-Values that should be installed based on where you live.
What Is The Best R Rating For Ceiling Insulation?
For cooler climates such as Melbourne, Sydney and Adelaide, we recommend at least R5.0 or R6.0 for the ceiling. For warmer climates such as Perth and Brisbane, we recommend at least R4.0.
What Type Of Insulation Is The Most Energy Efficient?
A high R Value means better insulating power and therefore greater energy efficiency. If your budget allows, we recommend upgrading to the highest R-Value you can afford as this will lead to greater temperature control and higher energy efficiency in your home.
Buy The Best Roof Insulation Online Today!
Pricewise Insulation supplies a wide range of high quality, affordable roof insulation products which perform very well in Australian climates. Order online today or call us on 1300 729 639 to discuss your project with one of our insulation specialists.