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What insulation should I use to internally insulate my solid walls?

Chris Brookman
Member Admin

There are many types of insulation you can use and there are some that we’d suggest you really shouldn’t. At Back to Earth we encourage people to move away from the seemingly high performance PIR foil faced foam insulations, including insulation backed plasterboard, partly to reduce the use of plastics and also because they tend to raise the moisture content of the walls they’re insulating. The knock on effect from this is that any timber seated in the wall will start to rot.

We would strongly recommend that you use not only vapour permeable insulations but also those that are capillary active, meaning they can transport, adsorb and release moisture vapour. In practice this usually means natural fibre insulation materials such as wood fibre insulation boards or other dense forms of natural fibre.

The ability to allow the passage of moisture but also to store and release moisture is what makes wood fibre insulation so useful. It helps regulate moisture levels in the wall during winter and prevents timbers seated in the wall, such as floor joists and lintels, from rotting. As the weather warms up again it releases moisture back towards the interior of the room and to the external environment, ready to repeat the cycle again the following Autumn.

Our range of internal wall insulations can be seen here -

Topic starter Posted : 09/03/2021 5:38 pm

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