When starting a construction project, the huge variety of materials to choose from can be overwhelming. There is the construction method to consider, whether to opt for traditional masonry or timber framed, in addition to services and finishes, and perhaps less obvious but nonetheless important: what insulation material to use.
Choice of insulation material depends on the situation in which it is going to be used. In typical masonry construction, as seen in many new builds and extensions, mineral wool insulation is often used to fill the cavity between two skins. Other common alternatives are rigid insulation boards made from different types of plastic foam, such as polystyrene or PIR.
While there are valid reasons to use these types of insulation, there are also many downsides: these materials contain hazardous chemicals which can be released during construction and, particularly in the case of PIR, may ‘off-gas’ throughout their lifetimes, a process through which volatile compounds are released into the air, worsening indoor air quality. These insulation types are typically more damaging to the environment, requiring more energy in production as well as being harder to dispose of sustainably at the end of their lifecycle.
Another key consideration is whether you are retrofitting your home. When undertaking a build on an existing property, whether an extension or simple internal refurbishment, this may present an opportunity to thermally upgrade you home – for more on this read our article about retrofitting! In this case, natural insulation is essential in allowing the existing building fabric to breathe, absorbing moisture and pollutants to keep your property healthy and avoid issues like mould growth.
Case Study: Wood fibre internal wall insulation in a historic Yorkshire cottage.
Wood fibre insulation offers a good alternative to less natural materials that are
commonly used in the construction industry. Made primarily of timber ground down into
fibres, often recycling waste material in its production, wood fibre produces far fewer
hazardous, volatile compounds while also being much friendlier to the environment,
both in manufacture and disposal (some wood fibre boards can be composted at the
end their lifecycle!). In many cases, there is also very little cost difference between
wood fibre and more standard insulation materials – so you can use more natural
materials without splashing out!
Some key things need to be considered when specifying wood fibre insulation, and it is
always important to discuss specifications with your architect or designer. Natural
materials typically have poorer thermal properties compared to inorganic alternatives,
so more is required to achieve the same performance, taking up more space. If using
internal wall insulation in a retrofit project, this can result in a noticeable reduction in
the size of rooms with external walls.
Nonetheless, wood fibre is a great example of a natural building material that can help
to make your home healthier, both for you and the building! If you’re considering
retrofitting an existing building, or even considering a more sustainable new build, wood
fibre might be the perfect solution.
