Installing insulation

With so many types of insulation product infiltrating the market it can be tricky to know what’s right for your project. Duncan Voice of Insulation Superstore discusses the various options

From sheep’s wool to plasterboard, panels to hemp, the multitude of different insulation materials on the market today means that there is now a product designed for every type of project – but with so many options available, knowing which to choose and where to use it is can be complicated.

The right materials can offer a raft of benefits for home occupants, not only providing a comfortable living and working environment, but also a reduction in home energy bills. Cutting corners on insulation is a risky business, and making the wrong decision can cause a of range of negative issues, including damp and a frosty interior which equals increased energy bills. With both problems requiring a heavy investment to put right, it’s a mistake self-builders simply can’t afford to make.

It is important to choose the best material and rating for your application and climate. Doing so will not only result in long term cost savings, but will also ensure a comfortable living environment. So, what is the right insulation for the job?

Small spaces

Thin insulation is ideally suited for application to small spaces, however it is vital that no compromises are made when it comes to performance. This is particularly important when insulating spaces such as garden buildings, including timber sheds, with occupancy comfort dependent on being protected from the elements all year round.

When insulating smaller spaces, improving air tightness is essential, and even upgrading the doors and windows will help considerably in reducing draughts. It is key to also focus on panel joints; eliminating any cracks or penetrations between roofs and walls to ensure the building envelope is completely sealed.

Up to five times thinner than traditional forms of insulation, multifoil is an ideal solution for smaller spaces. Achieving the same performance as its thicker counterparts, multifoil insulation ensures a comfortable internal environment all year round, with its reflective surface acting as a barrier to thermal transfer, resulting in significant energy savings.

Larger spaces

Large areas, such as basements or lofts, often require a higher investment to ensure maximum gain, but with benefits including reduced energy costs, an improved efficiency rating and a low carbon footprint, it is often a safe bet, with high returns. Attention also needs to be paid to meeting Building Regulations, which dictate the expressed U-values that need to be achieved which are based on the application, building type and location.

Insulation materials must be evaluated based on several crucial factors to ensure their suitability for a project, including lifespan, ease of installation, impact on the construction envelope, and how the material terminates into windows, doors and fixtures. Any gaps, cracks or penetrations will compromise insulation performance, as well as attracting unwanted draughts.

Flexible materials such as spray foam or mineral wool are relatively simple to install; spray foam requires only require a hole in the wall for application into the cavity of an empty room, such as a loft. However, this method poses a risk of over-pressurising the wall, leading to potential warping. High performing partial fill cavity wall insulation board can be a better option, with the thinner solutions easily meeting target U-values while offering an enhanced thermal performance.

Rigid phenolic insulants such as Kingspan’s Kooltherm K are suitable for roofs, walls and floor applications. The products are unaffected by air infiltration and with their design resisting both moisture and water vapour ingress, they can provide a reliable thermal performance for the lifetime of a building, making them a trusted option for the insulation of large areas.


When selecting insulation for use in any building with multiple occupants, attention should focus on materials which provide excellent acoustic performance. Materials should impede the transmission of sound through a structure or absorb it into the surrounding surface area to reduce the impact of internal noise, as well as external noise pollution such as traffic or even loud neighbours!

Made from volcanic rock, products like Rockwool’s acoustic slab traps sound waves and dampens vibrations, and are easy to install around fittings and fixtures. Stone installation also has the added bonus of providing exceptional fire performance qualities – a necessity in any residential building.

Existing buildings

Ease of installation is an important factor when working with an existing building and should determine the type of insulation used to limit the impact on the building as much as possible – particularly if you are still living in it.

Materials such as SuperFOIL SF19BB can be fitted from a building’s exterior, removing the need for internal access. These also don’t require the raising of a roof, which can be an issue when it comes to Building Regulations and planning conditions. Intelligent breather membranes of this kind also respond to changes in the environment, with vapour permeability adapting as required to reduce the risk of condensation, making for a comfortable living environment.

The product’s lifespan and overall performance should also be considered for any installation; materials with long lifespans will likely not require further investment and disruption in the future, while high performing materials will of course improve efficiency and occupant comfort.

Duncan Voice is manager at Insulation Superstore