Can You Use Expanding Foam as Cavity Wall Insulation?


Can You Use Expanding Foam Insulation as Cavity Wall Insulation?

Yes, you can use expanding foam insulation as cavity wall insulation. Expanding foam is often found in the form of spray foam insulation as it is the easiest method to apply the reactive, two-component mixture that expands once blown.

Expanding foam insulation can be applied to any surface to prevent draughts and enhance structural integrity, thus making it ideal for cavity walls. Cavity walls consist of two layers of brick walls separated by a gap and are found in almost all houses built after the 1930s. As masonry is an absorbent material, cavity walls are used to slowly drain humidity from the wall, and from the inside of the house to the outside. The gap ensures that water drains effectively through weep holes at the base, and that air and evaporated water can move to the outside.

cavity wall fibreglass insulation instead of spray foam insulationDo I need cavity wall insulation?

If the cavity is more than 50mm in-depth and/or your energy bills are high, insulation is highly recommended. You can tell if you have a cavity wall by looking at the brickwork, or by reaching out to an insulation contractor. Building regulations now specify that walls must adhere to specific U value standards (thermal transmittance) so many properties already have cavity wall insulation. If you do, and it consists of blown mineral fibre or polystyrene beads and you’re still receiving high energy bills, we recommend switching to expanding foam insulation. Mass Foam Systems are BBA certified, offering Icynene® spray foam insulation across the UK as an effective cavity wall insulation.

How expanding foam cavity wall insulation works

Our expanding foam insulation product, Icynene®, is an environmentally friendly one step spray foam insulation that insulates and air seals for the life of your home or commercial building. It is applied by blowing into holes that are carefully made in the bottom exterior of the wall, which spreads and expands across the cavity.

Why should I use cavity spray foam insulation?

The Energy Saving Trust estimates savings of up to £225 a year from effective cavity wall insulation. As it is applied from the outside, it creates minimal downtime and provides instant insulation! Other benefits of using Icynene® expanding foam insulation include:

  • Icynene® provides U value insulation and air sealing, cutting your home’s energy loss
  • Icynene® reduces air pollution and protects against mould growth
  • Icynene® reduces drafts and noise
  • Icynene® enhances structural integrity

Wall foam DIY

Spray foam insulation can be installed by yourself but will require a lot more planning and extra work. It is highly recommended that you do not install spray foam yourself because the costs involved in making small mistakes can far exceed the cost for a professional installer. Extra items such as equipment, surroundings and safety precautions can immediately exceed a person’s budget if installing insulation in 1 area of the house. Professional installers benefit from the ability to reuse and recycle equipment which is why our company, Mass Foam Systems, can guarantee the lowest price guarantee on Icynene spray foam. Check out our DIY costs guide for a more in-depth overview of this topic.

Learn more about Icynene® expanding foam insulation by reading our Icynene® reviews and Icynene® cost details. Get in touch with an accredited Icynene® contractor for cavity wall insulation by calling us for a no-obligation quote on 0800 246 5051 or get an instant quote.

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