Debate on provision of cavity wall insulation under government grants

Summary

The UK Government funds the installation of cavity wall insulation (CWI) with grants and also requires energy suppliers to provide insulation and energy efficient measures (mandated schemes).  Most of the schemes are targeted at lower income households living in less energy efficient properties. Some schemes are taxpayer funded, others are delivered by energy suppliers and funded through a levy on energy bills.

The government has estimated that 14.8 million homes across Great Britain had cavity wall insulation at the end of 2022; 71% of homes with cavity walls.

The government has published guidance for householders who suspect they have had faulty cavity wall insulation installed at their properties and there are quality assurance schemes for government mandated or funded installations and agencies providing guarantees for CWI.

There is no government compensation scheme for problems with CWI.

What is cavity wall insulation (CWI)?

Cavity wall insulation (CWI) is a type of insulation that can be applied to some buildings that have external and internal walls separated by a gap. It fills the gap between these walls to prevent heat loss and increase energy efficiency. Current new builds are constructed with insulation, but older, un-insulated properties can be retrofitted by drilling small holes into the external wall and pumping insulation (mineral wool, polystyrene beads, or foamed insulants) into the gap before the holes are refilled.

Government support for CWI

The UK Government funds the installation of CWI with grants and also requires energy suppliers to provide insulation and energy efficient measures (mandated schemes).  Most of the schemes are targeted at lower income households living in less energy efficient properties. Some schemes are taxpayer funded, others are delivered by energy suppliers and funded through a levy on energy bills.

Government mandated schemes

The following schemes are supplier-led and are available across Great Britain

• The Energy Company Obligation (ECO) is a government energy efficiency scheme in England, Scotland and Wales designed to tackle fuel poverty and help reduce carbon emissions, focused on supporting low-income households. ECO is an obligation, placed on energy suppliers with over 150,000 customers to deliver measures such as insulation, first time central heating, renewable heating, solar panels, and district heating connections to domestic premises.
• The Great British Insulation Scheme (GBIS) is a government energy efficiency scheme in England, Scotland and Wales formerly known as ECO+. It is designed to complement the ECO scheme and boost help for those on the lowest incomes, as well as extending support to a wider range of households living in the least energy efficient homes and in the lower Council Tax bands

Government funded (grant) schemes

• The Green Homes Grant: Local Authority Delivery (LAD) scheme (England) was launched in August 2020 with the aim of upgrading the energy efficiency of 50,000 homes of low-income households. Funding is paid to local authorities.
• The Home Upgrade Grants (HUG) scheme (England) provides energy efficiency upgrades and low carbon heating to low income households in properties which are off the gas grid and in energy efficiency bands D to G. Funding is paid to local authorities.
• The Social Housing Decarbonisation Fund (England) aims to upgrade ‘significant’ amounts of social housing stock to EPC band C or higher. Funding is paid to local authorities and social housing providers.
• The Green Homes Grant voucher scheme (England), which is now closed, provided grants to homeowners and landlords to make energy efficient improvements to homes.

Further information on the various schemes can be found at the government webpage Find energy grants for your home (Help to Heat)  and in the Library briefings, Help with energy efficiency, heating and renewable energy in homes and Energy efficiency of UK homes  (which includes schemes in Scotland, Wales and Northern Ireland).

Cavity wall insulations carried out under government schemes

1.04 million cavity wall insulations were carried out in Great Britain through the Energy Company Obligation (ECO) between 2013 and 2023. This was 27% of all heating and energy efficiency measures carried out under the scheme. The annual number of cavity wall insulations provided through ECO has fallen over time from a peak of 316,400 in 2014 to a low of 11,100 in 2023.[1]

The following chart looks at longer term trends in cavity wall insulations carried out under ECO, its predecessor schemes,[2] the Green Deal plus the Government funded schemes in England which were introduced in 2020.[3]

There was a large drop in the number carried out in 2013 when ECO replaced existing schemes. There was a small increase at the start of 2014, but this was reversed from 2014 when the ECO scheme was scaled back. More details are given in the Library briefing Energy efficiency of UK homes.

When the proportion of properties with any type of insulation increases to high levels or ‘saturation point’ we would expect the smaller remaining number of uninsulated properties to be harder to treat and for the number of insulations carried out to fall even with the same level of ‘effort’ and/or funding.

However, there is no evidence that the UK is near this ‘saturation point’ for cavity wall insulation. The government has estimated that 14.8 million homes across Great Britain had cavity wall insulation at the end of 2022; 71% of homes with cavity walls.[4] 3.8 million homes with uninsulated cavity walls were thought to be ‘easy to treat’ and the remaining 1.3 million ‘hard to treat’[5].[6]

CWI issues

Customers who have problems with CWI are advised to first try and resolve the issues with the original installer. When the issue cannot be resolved, or the installer has gone into liquidation, the customer can check if they have a guarantee, such as with the Cavity Insulation Guarantee Agency (CIGA). Guarantee agencies should assess damage and find a resolution; there is an independent arbitrator for CIGA decisions.

The government has published guidance for householders who suspect they have had faulty cavity wall insulation installed at their properties (or have been contacted by a claims management company: Cavity wall insulation (CWI): consumer guide to issues arising from installations (2019).

There is no government compensation scheme for problems with CWI.

Quality assurance

Measures installed under ECO (since 1 January 2020), GBIS, HUG and LAD are covered by Trustmark, a government endorsed quality scheme for work done on homes, or similar certification bodies. This requires businesses installing measures to provide additional consumer protections, including insurance against the tradesperson going out of business, a minimum 2-year warranty for work, and a minimum 25-year guarantee for certain measures installed under ECO. Trustmark’s webpage If things go wrong has guidance on making a complaint. It advises that customers speak to the business in the first instance, before escalating the concern to the scheme provider if the issue cannot be resolved directly, and then in turn to the business’ alternative dispute resolution (ADR) provider and the Dispute Resolution Ombudsman. Ofgem’s FAQs for domestic consumers and landlords has advice on steps that consumers with ECO installation problems may take. This advice also applies to installations made under earlier ECO schemes.

Cavity Insulation Guarantee Agency (CIGA)

There are a number of agencies providing guarantees for CWI. One of the main organisations is the Cavity Insulation Guarantee Agency (CIGA), who provide 25 year guarantees for CWI fitted by CIGA registered installers. All registered members of CIGA are assessed for competence and must follow the technical guidance for the material used and CIGA Best Practice Guidance.

(CIGA) has a published complaints procedure which aims to settle disputes directly with the CIGA member.

Rights under any guarantee are in addition to a consumer’s statutory rights against the trader under both the Consumer Rights Act 2015 and the Supply of Goods and Services Act 1982.

Further information on quality assurance and guarantees is provided in the Library briefing Q&A: Cavity Wall Insulation.

Government policy on consumer protection

The Competition and Markets Authority began a review of consumer protection focusing specifically on business practices, consumer experience and standards in the green heating and insulation sectors:  Consumer protection in green heating and insulation sector (September 2022).  It provided an update on 21 February 2024, which said that, “Overall, standards bodies have engaged positively with the principles. However, more still needs to be done to improve the levels of consumer protection.”

The Government responded in a written statement also on 21 February 2024:

“The Government acknowledges the findings on consumer experience, where some consumers may face difficulties when carrying out retrofit work, and on standards, where the landscape offering protections for consumers can be seen as complex and confusing to navigate.”

The statement summarised the actions it was taking to protect all consumers undertaking home retrofit work.

In a debate on Cavity Wall Insulation: Government Support, also on 21 February 2024, the government acknowledged that there were, “poorly executed installations of cavity wall insulation,” and stated that it was, “fully committed to protecting all consumers who have insulation products installed in their homes, as well as improving the overall consumer journey regardless of housing tenure or how installation work is funded.”

[1]      DESNZ, Household Energy Efficiency Statistics, headline release February 2024 (Table 3.1)

[2]      The Carbon Emissions Reduction Target, Community Energy Savings Programme and Warm Front (in England)

[3]      Social Housing Decarbonisation Fund, Homes Upgrade Grants and the Green Homes Grant: Local Authority Delivery scheme

[4]      DESNZ, Household Energy Efficiency Statistics, detailed report 2022

[5]      These are more difficult or more expensive to fill than standard cavities. This includes properties with a narrow cavity and properties of either concrete or metal frame construction.

[6]      DESNZ, Household Energy Efficiency Statistics, detailed report 2022