Insulation Options

This section is compiled from manufacturer’s information, customer’s feedback, and many years of experience supplying and installing insulation. Having been in the industry for a number of years, we are well informed about the various insulation options available to home owners. This is not intended to be a comprehensive technical guide, but we hope that the information below can help you to make sense of some of the most popular insulation options available, and assist you to make an informed choice about which insulation options you decide to go for.

Check out our Pink Batts vs Earthwool blog article for a more direct comparison between these two brands.

Insulation Options – Thermal Wall, Ceiling and Underfloor

Customers choose different insulation options for various reasons. The 3 most popular brands of thermal insulation that we sell are Knauf Earthwool GlasswoolBradford Gold Insulation and Autex GreenStuf Polyester. The common factors for these brands are that they are safe and relatively easy to install, are non-combustible, and are available in a range of “R Values” to suit different climate zones. They all come conveniently packaged in plastic or poly bags which are relatively easy to carry around and transport.

Bradford Gold vs Pink Batts

Both the Pink Batts and Bradford Gold brands are synonymous with quality glasswool insulation. Bradford Gold is more expensive across the board, and some installers claim that the rigid density of the insulation segments make for faster installing compared to the cheaper Pink Batts brand. Also, Bradford Gold insulation is backed by a 70 year warranty, which is about as good as it can get. (Pink Batts is backed by a “life time” warranty, meaning the life of the building into which it is installed.)


Comfort and Ease of Handling

Insulation manufacturers have come a long way in making their insulation more pleasant to work with. Bradford’s Gold thermal insulation range has undergone noticeable improvements, and the glasswool of today is definitely less itchy to work with compared to 10 – 15 years ago. Knauf Earthwool Glasswool is considered by many to be the most pleasant to work with of the glasswool range, mainly due to the non-itch factor, the fact that it is practically odourless, and the easy cutting/installing. GreenStuf Polyester is a different kind of insulation altogether, and being made from polyester, is arguably one of the cleanest and most comfortable material to insulate walls, ceilings and underfloors with. Green Stuf polyester generates no excessive dust, and can be easily torn to the required length, while glasswool insulation requires a sharp knife to cut in either direction.

DIY Video: How to Choose the Right Insulation

Allergies and Asthma

Bradford has partnered with the Sensitive Choice® programme offered by the Asthma Foundation of New Zealand., and Autex GreenStuf insulation, which is made from 100% polyester, contains no breathable sized particles and is as such considered to be 100% safe for asthma sufferers. While the green stuff insulation material itself is safe for asthma sufferers, dust and other particles may become airborne during and after insulation installation.

Storage and Transport

Earthwool segments are exceptionally well compressed, making it by far the easiest and cheapest insulation to store and transport. You can easily fit over 500 sqm of R2.2 Earthwool wall insulation on the back of a one tonne ute, which is almost twice the equivalent Bradford Gold and almost three times the amount of GreenStuf Polyester. This can be an important consideration if you are going to be picking up the insulation yourself or paying for freight to an area out of the standard delivery zones.

Pink Batts Snug Floor Insulation - Installed in an underfloor
Pink Batts Wall Insulation Batts installed in a New Zealand home

Pink Batts Roof Insulation installed in a New Zealand home

R Values and Thermal Properties

The R-value of insulation measures the thermal resistance of the insulation. Therefore the “thermal insulating effect” of the one brand shouldn’t differ from another brand with the same R-value, if it is properly installed.

When you insulate walls, the R-value option is usually limited to the thickness of the wall stud, i.e. the space inside the wall cavity. This is typically either 75mm or 90mm, but sometimes 140mm.

Significant energy savings when you insulate roof space

With ceiling insulation, the R-value is generally not limited to space, so the question is more how much insulation you need. Higher R values will increase the level of thermal protection, which in turn can help to reduce your home’s power consumption. As electricity prices rise, an increasing number of homes are finding that the savings in their power bills over time more than justify the initial decision to insulate walls, ceiling and underfloor.

If you currently have no insulation in your ceiling, then even a small layer of thermal insulation will make a significant and noticeable difference. GreenStuff Ceiling Insulation Pads are available in R values of up to R3.4 and the blanket rolls are available in values of up to R3.6. Earthwool Glasswool Ceiling Segments are available in up to R6.3 and the ceiling rolls come in up to R3.6.

Remember to insulate between floors

When considering which insulation options are the most appropriate for your home, don’t forget the underfloor. A raised timber floor with no insulation will often remain the “cold spot” in winter, even if the air in the room is maintained at a comfortable temperature. Green Stuf Polyester Underfloor insulation is available in R1.5 and R1.8, and Bradford’s Optimo Underfloor insulation comes in R2.6. Knauf Earthwool Glasswool Underfloor segments are available in R1.8 and R2.2 and the underfloor rolls are available in R1.8 with a new wind wash barrier. Insulate under floor for comfort and energy savings.

Durability and Warranty

If installed correctly, insulation should last as long as your home. The various manufactures nonetheless provide various product warranties. Earthwool Glasswool and Autex GreenStuf are each covered by a 50 year warranty and Bradford Gold states a 70 year warranty.