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Internal Wall Insulation

Specialist Internal Wall Insulation Installers

Internal Wall Insulation (IWI) is an extremely effective means of insulating solid wall properties to significantly reduce the amount of heat lost through the walls.

The installation process involves fixing a layer of insulation material to the internal walls of a property, finished with plasterboard to leave a smooth and clean surface for redecoration. Decoration and the movement of fixtures and fittings are generally included within the installation package.

Cornerstone specialises in the insulation of solid wall properties and has internally insulated countless domestic properties all over the UK, including private and social housing, as an alternative solution to External Wall Insulation (EWI).

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Is my home suitable for IWI?

If your home was built before 1920, it will most likely have solid external walls with no cavity. The lack of a cavity means more heat can escape from your house through the walls.

Internal wall insulation is applied to the internal face of a property’s external walls and can often be the single biggest home improvement you can make to reduce heat loss. The insulation makes it much more difficult for the heat to pass through your walls, keeping as much of it as possible inside your home for as long as possible.

You should be able to tell which wall type you have by looking at the brickwork on the outside of your house. If your home has solid walls, you will be able to see a pattern showing the long and short side of the bricks like Fig A.

If your home has cavity walls, you will only be able to see the long side of the bricks like Fig B.

IWI is suitable for all properties but is most often installed in homes where External Wall Insulation (IWI) is not appropriate, such as listed buildings or those located in a conservation area. While IWI may impact internal living space and be more disruptive throughout installation, it is often cheaper, quicker and less complex to install than EWI and won’t require planning permission.

The benefits of internal wall insulation

Uninsulated solid walls can leak up to 45% of a property’s heat – insulating these walls can save up to £425 per year on your energy bills.* Solid walls can be insulated internally or externally, with the cost depending on the property size and condition. Internal Wall Insulation (IWI) offers a number of benefits:

  • Creates a warmer and more comfortable home
  • Significantly lowers your energy bills
  • Improves the appearance of your property

Depending on your household circulstances, funding could be available to contribute towards the cost of IWI.

Find out more about grants

Potential Savings

The cost of IWI varies between properties, from around £4,000 to £12,000 depending the on the size and condition of a property.

Approximate Annual Energy Bill Savings*

Save around £425

*Figures from the Energy Saving Trust, based on insulating a gas-heated home

Approximate Annual Energy Bill Savings*

Save around £255

*Figures from the Energy Saving Trust, based on insulating a gas-heated home

Approximate Annual Energy Bill Savings*

Save around £160

*Figures from the Energy Saving Trust, based on insulating a gas-heated home

Approximate Annual Energy Bill Savings*

Save around £175

*Figures from the Energy Saving Trust, based on insulating a gas-heated home

SCIS Forecasted Carbon Reduction in 2020

308,641
tons of carbon saved in 2020.
That's equivalent to
300,000+
new trees planted.
That's
260
football pitches of new rainforest or woodland.
And also equal to
81,563,300
Km of air travel around the world 2,003 times!

What our clients say...

I wanted to show my appreciation for the work that your team carried out at my property last year. Although I was unsure whether I should contact you, your very knowledgeable team filled me with confidence so I decided to proceed. The cavity wall extraction that I had done has completely sorted out the damp I found inside my living room. Thanks to you and your team. I will surely be recommending SCIS to anyone who asks.

Debra
Winchester

Thank you for all the team at SCIS for the extremely professional service that you have delivered in our properties for our tenants. I was particular impressed with the detail and knowledge throughout the process. The guidance during initial consultation and survey through to the quality of after care following installation was exceptional. Thanks again.

Sue
Portsmouth