What is wood fibre and how is it made?

Wood fibre insulation was introduced about 20 years ago, after the engineers from the timber producing areas of Europe devised new ways of transforming timber waste into insulation boarding.

The success of wood fibre insulation is all thanks to an attractive and environmentally friendly profile with a number of functions, including rigid insulation for floors and roofs as well as insulation for studs and rafters.

Wood is of course renewable, it locks in carbon during growth and is relatively free from pollution. It also has typically low u-values, meaning it is an effective material as an insulator as it lets little heat pass through (as shown in this diagram below).


Graphics courtesy of www.thegreenage.co.uk

Another key feature is the breathability of wood fibre, which helps moisture to be regulated as well as the density of the material which adds a degree of decrement delay (in simple terms, takes longer for heat to pass through) which is always useful for those hot summer days and prevents the building turning uncomfortably hot. When we refer to wood fibre being ‘breathable’ it also relates to the hygroscopic nature of the product. This is the ability of the material to absorb and release moisture from the atmosphere as the humidity rises and falls.

Pro’s and Cons’.

 Wood fibre is usually imported from another country which adds to its embodied energy.

It’s treated with paraffin wax which derives from a petrochemical substance. 

↓ Rigid boards can be fragile.

Wood fibre contains a high percentage of what would otherwise be waste material. 


↑ Locks in co2 emissions during tree growth.

 Hygroscopic – meaning it provides humidity control to prevent damp.

↑ Decrement delay – meaning it takes longer for heat to pass through.

 Finally, and usually the most attractive, it significantly reduces energy costs to the home.

Although Wood fibre is typically the most expensive material we use for insulation, it undoubtedly has the most benefits. With the breathability of the product, you can rest assured your externally insulated property will keep your home cosy, whilst the carbon neutral aspect of the material will give you that peace of mind in knowing you’re significantly reducing your Co2 emissions and therefore contributing to saving our planet.


Written by Leanne Groves.