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Last updated: 30 July 2023

Cavity Wall Insulation Grants: Everything You Need to Know

Did you know that, on average, a house loses 20%-30% of it’s heat through improperly insulated external walls? Yes you heard that right.

Keeping their home warm is usually every homeowner’s top priority during the winter months. However, loss of heat through external walls doesn’t only make the task more difficult, but it also leads to a higher cost of energy bills.

Fortunately, there is a way to solve this frustrating issue: cavity wall insulation.

Insulation is not just one of the best ways to lower your electricity bills, it is also a great way to keep the environment safe. This is because it reduces the overall carbon emissions from your home. The best part? You can avail free cavity wall insulation through the Energy Company Obligation (ECO) scheme or Green Homes Grant that’ll make the job 10x easier.

If you’re looking for more information about cavity wall insulation and grants offered by the UK government, you’ve come to the right place. This article includes all the information you need about cavity wall insulation grants to make an informed decision.

Cavity Wall Insulation? What Is It?

If you’re looking to improve thermal efficiency in homes with cavity walls then cavity wall insulation is among the easiest and quickest ways to do so. To understand how it works, we must first understand what a cavity wall is.

A cavity wall comprises two walls with a gap in between (hence the name cavity) for those who don’t know. All homes are built with cavity walls in the UK after 1920. Unless your home was built in the past 20 years, chances are those cavities are probably empty and not insulated.

With that information out of the way, let’s dive into the crux of the matter. Cavity wall insulation is a process that involves filling walls with either polystyrene beads or mineral wool. This is done from the outside of the walls. This makes an effective insulation barrier – keeping the cold temperatures at bay and preventing the hot air to escape. This, in turn, keeps your home warm for longer.

According to The Energy Saving Trust, uninsulated walls contribute to one-third of heat loss in a home. Insulated cavity walls can be a great way to deal with this problem, keeping your heating costs low and the environment safe.

Benefits of Cavity Wall Insulation Grants

In case you’re wondering, here are some benefits of availing the cavity wall insulation grants:

Low initial cost

The initial cost of cavity wall insulation is unaffordable for many people, but thanks to these home insulation grants, you can get your home insulated at a fraction of the original cost or even for free if you belong to a low-income household.

Reduction in energy bill

The home insulation grants offered by the UK government are meant to make insulation more affordable. This, in turn, helps reduce heating costs as improper insulation contributes to 35% of heat loss in homes (on average).

Professional work

Perhaps the biggest benefit that these cavity wall insulation grants offer is that the insulation work is done by experienced and vetted professionals who are selected by the government. So, you can expect quality work with hardly any faults.

When Should I Opt for Cavity Wall Insulation?

You should consider getting your cavity walls insulated only if:

  • Your home is less than 12 metres (about four storeys) high
  • The external walls are made from unfilled brick walls with at least 2 inches wide cavity in between
  • The brickwork or masonry is in good condition
  • The external walls in your home are accessible. If some of them are joined with the adjacent house, a cavity barrier will have to be installed, which can add to the total cost
  • The internal walls in your home are dry. If there are any damp patches, you’ll need to get the cause sorted out before proceeding with the insulation process
  • There are no areas of steel or timber-framed construction

Types of Cavity Wall Insulation

Below are the three main types of cavity wall insulation:

  1. Polyurethane foam (PUR) – PUR is a fluid-like material that offers seamless insulation without any thermal bridges. It expands and fills the gap once injected into the cavity. PUR is the most effective form of insulation, but it’s the most expensive one as well.
  2. Polystyrene beads or granules – This insulation material is supplied loose or with light, sticky resin to hold the beads together. The beads/granules are blown into the cavity using compressed air. Although polystyrene beads are cheaper than the other two options, keep in mind that they aren’t as effective.
  3. Blown mineral fibre – This is the most environmentally friendly insulation option. It comprises of fibreglass flakes that have little impact on the environment. Blown mineral fibre is also blown into the cavity using compressed air, like polystyrene beads.

About Cavity Wall Insulation Grants

There’s no doubt that insulation can lower your energy bills. However, some people still find it hard to justify the exorbitant cost of installation.

If you’re one of these people, you’d be happy to know that there’s a way to get your cavity walls insulated without spending a huge sum of money. Yes, you read that right. There are two major grants that have been rolled out by the government to provide assistance to homeowners in the UK with cavity wall insulation.

The Energy Company Obligation (ECO)

The Energy Company Obligation (ECO) is a government energy efficiency scheme introduced in 2013. As the name suggests, this scheme imposes an obligation on certain energy and installation suppliers to support low-income, fuel-poor, and vulnerable households in heating their homes.

However, not all UK residents can reap the benefits of this scheme. The eligibility criteria for the ECO scheme states that to avail of the scheme, you must either be a core group customer from scheme year 9 onwards under the Warm Home Discount Scheme, or you must receive at least one of the following benefits:

  • Armed forces independence payment
  • Attendance, carer’s, or constant attendance
  • Child benefit or child tax credits
  • Disability living & severe disablement allowance or industrial injuries disablement benefit
  • Income-based employment and support allowance, income support, or income-based jobseeker’s allowance
  • Pension guarantee credit or war pensions mobility supplement
  • Personal independence payment
  • Tax credits, universal credit, or working tax credits

Green Homes Grant

The Green Homes Grant is a scheme for the general homeowners and landlords in England. Under this scheme, you can get vouchers worth up to £5,000 for energy-efficient home improvements.

This means that all types of home improvements, including double glazing, insulation such as loft insulation, wall insulation and so on, boilers, energy-efficient doors, and energy-saving light bulbs, will be covered in this voucher.

For the general public, the voucher is supposed to cover two-thirds of the total cost (with a limit of £5,000. So, for instance, if you get insulation worth £6,000, you’d have to pay only £2,000. The rest will be covered by the voucher.

And that’s not it; low-income households won’t have to pay anything as they can get vouchers of up to £10,000. Details about which homes qualify as low-income ones are available on the official government websites.

How to Apply for Cavity Wall Insulation Grants

To apply for a cavity wall insulation grant, you’ll have to fill out an online application with basic information about yourself and your home. You can do this on any government authorised website, and an official will get back to you with information regarding the next step.

Frequently Asked Questions

Who approves the Cavity Wall Insulation Grants?

This grant money is approved by the Green Homes Grant, which is directly associated with the Government Energy Company Obligation (ECO) scheme. The scheme is managed by Ofgem and other official authorities, meaning it’s 100% legitimate.

Besides this, ECO grants focus on reducing carbon emissions from homes and help the UK government meet their targets, which is why you won’t witness any shortage of funds. Not to worry though as these grants are very well-funded.

Do I really have to pay nothing?

Yes! You can avail of the grants and get your cavity walls insulated for free, given that you meet the eligibility rules. There’s no catch, and you’ll never have to repay the grant.

What to do if my property goes on rent?

Not an issue. Like all properties, your rental property is still entitled to this grant as long as the tenant is in accordance with the eligibility criteria. The tenant’s Energy Performance Certificate (EPC) must be either A, B, C, D, or E. People belonging to group F or G aren’t eligible for the grant.

How long does the work take?

The entirety of the work depends on the size of the property. However, it is usually done in a day. It doesn’t cause much disruption as the work is done outside the home.

Can I do the insulation work by myself?

That’s a good idea only if you’re a professionally experienced insulation installer. Otherwise, we wouldn’t recommend it as faulty insulation can cause problems like mould, condensation, and no reduction in heat loss.

How long will the insulation last?

If done right, cavity wall insulation has a life of at least 40 years. If not done right, it can still last a good 25 years. So once it’s done, you don’t have to worry about it for the rest of your life if you get it done in the near future.

What are the eligibility criteria for Cavity Wall Insulation Grants?

The primary deciding factor for Green Homes Grant is your income. It offers mid-tier households some relief, while low-income households do not have to pay anything at all.

Besides this, you might be eligible for the ECO scheme if you belong to a low-income group or are receiving certain benefits discussed above. However, this doesn’t mean that only individuals receiving these benefits are eligible for the grant.

It’s always best to inquire as you might be eligible for funding in some cases.

Where can I find more information about this?

You can find out more about the Cavity Wall Insulation Grants on multiple official government websites.

The Bottom Line

Cavity wall insulation is an excellent way to reduce your heating bills and carbon emissions from your home. It also improves your overall quality of life by properly insulating your home, and there’s no reason why you shouldn’t go for it when you have two cavity wall insulation grants available to support the installation.

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