Is Polyester Insulation Better Than Glasswool?

Pricewise Insulation often receives enquiries about whether polyester insulation is better than glasswool. Both polyester and glasswool (also called fibreglass) insulation are highly recommended products and very effective in reducing heat transfer. They are both safe products to install and handle. Customers enquiring about the different types may have noticed a difference in price and wondered if it’s beneficial to go with the more expensive Autex Greenstuf. The truth is, both kinds of insulation have their merits and it really comes down to the individual needs of the customer.

Comfort of Handling

Polyester is typically more expensive but has two attributes which arguably could cause it to be considered a ‘premium’ insulation product. Polyester insulation has practically speaking no breathable fibres, and as such may be favoured by people suffering from asthma or severe dust intolerance. It is also completely ‘itch free’ to handle and install, whereas most people experience at least a minor temporary itch e.g. on their wrists after handling glasswool insulation for a few hours.

Should I wear safety gear when installing insulation batts
Safety gear is recommend when installing glasswool
Photo of a professional installing CSR Bradford Insulation Hi-Performance Gold Ceiling Batts in a roof space
Modern day glasswool is far less itchy to work with
photo of a man installed bradford polymax polyester ceiling insulation in the roof of an existing home
Polyester ceiling insulation is perfect for people with allergies

Glasswool Much Improved in Recent Times

It is important to note, however, that the glasswool insulation of today is very different to the stuff that was sold on the market a few decades ago. The installers of those days would recall extreme discomfort, whereas the glasswool insulation today, particularly Knauf’s Earthwool, is much more pleasant to handle.

Higher Compression Properties with Glasswool

Most glasswool insulation has a much higher compression factor than polyester insulation. This may give it an advantage from a delivery and storage point of view. Customers may be able to fit the required amount of glasswool insulation in the back of their car or ute but be unable to fit the equivalent number of bags of polyester insulation. Opting for the glasswool insulation may save them an extra trip back to the warehouse or the cost of having it delivered. If onsite storage is an issue, it may be better to purchase glasswool insulation.

Consistent R-Value Regardless of the Material

Neither polyester or glasswool insulation will outdo the other in performance. Glasswool insulation is the cheaper option, but it performs just as well as its polyester equivalent. R-value is a measure of how effective the insulation is at resisting heat transfer, regardless of what it is made out of.

Compare Prices Including Delivery Charges

When comparing insulation prices across brands, always factor in any potential delivery costs. It could be that a more expensive brand ends up cheaper overall because it comes with a lower delivery cost. The reason for this is likely to be your location. It may be that your site is located close to an insulation manufacturing plant, so it won’t cost a lot to deliver it to you.

When you order from Pricewise Insulation, we may suggest that you go with a different brand with similar properties in order to be able to offer you a better deal.