Spray Foam Insulation or Fibreglass Insulation?

Home Spray Foam Insulation or Fibreglass Insulation?

Spray Foam Insulation vs Fiberglass Insulation

All these mixed reviews on the internet have confused you about whether spray foam insulation is better than fiberglass insulation.


Don’t worry! – We have noticed all the confusion and have decided to make your life easier. So sit back, scroll and read about the differences.

Fibreglass Insulation

Spray Foam Insulation or Fibreglass Insulation

Pros of fibreglass:

  • Fibreglass is an inexpensive insulation choice
  • Fibreglass is does not shrink
  • Fibreglass is not flammable
  • Is environmental friendly, using recycled glass
  • Fibreglass has an U-value of 0.3

Spray Foam Insulation

Pros of spray foam insulation:

  • Spray foam is 100% water blown; making it eco-friendly
  • Spray foam is a fire retardant insulation
  • Prevents air leakage
  • Reduces risk of mould
  • Spray foam insulation has an average U-value of 0.25

What is…

..Fibreglass Insulation?

Fibreglass is a popular insulation option within the market. Developed in the 1930s, the candy floss-like insulation is the go-to insulation method to date. This is no surprise as fibreglass is one of the cheapest insulation methods, whilst  providing similar qualities as to the more pricer alternatives. Coming in two options, blankets and loose fill, this insulation has been populating the homes around the UK for centuries.

..Spray Foam Insulation?

Spray foam is a revolutionary insulation option which has taken the UK by storm within the past several years. The spray foam insulation has become increasingly popular due to its unique characteristics. With the ability to expand 100 times its original size, makes it ideal to seal all gaps to prevent air leakage.

How is it installed?

Fibreglass insulation

As you may know by know fibreglass comes in two forms; blankets and loose fill. Why? This is as depending where the insulation is going (between timbers, underfloor, loft floor) the installers will choose the most suitable one.

Loose fill is applied to the floor of a loft, so this would be installed using a hose. Picture a fire fighter carrying a hose and that is exactly what it would look like. Installers will spray enter your home with a huge hose and spray the confetti-like fibreglass across the loft floor.

Fibreglass blanket is installed different. The candy floss-like insulation is rolled out and cut to size of your timbers and stuffed in.

Spray Foam Insulation

As the name suggest spray foam insulation is installed by a unique technique called spraying. Similar to fibreglass loose fill, spray foam requires a hose that will be bought into the loft. The foam is sprayed onto the wall and expands. Requires no surgical-percise cutting so it will not miss any gaps and crannies.

Cons of…

…fibreglass Insulation

We must remember fibreglass has been around from the 1930s and is still such a popular choice. There must be a reason for this. Simple! It is such a remarkable product. Well you would think. However, every insulation has its downfalls. Some greater than others.

  • Blankets of fibreglass struggle to cover all gaps and crannies
  • Fibreglass contain harmful glass particles that can cause respiration irritation

…spray foam insulation

Spray foam is a ground-breaking insulation method which has become a market phenomenal. But, as you know everything has there good side and bad side.


  • Can be messy upon application
  • Not DIY-friendly. Spray foam has to be installed by competent installers.