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External Wall Insulation

How much does external wall insulation cost?

When it comes to home insulation, external wall insulation plays a crucial role in enhancing energy efficiency and comfort. Whether you’re renovating an existing property or embarking on a new construction project, understanding the cost of external wall insulation is essential. 

External wall insulation not only helps regulate the temperature inside your home but also contributes to significant savings on energy bills over time.  

Understanding external wall insulation 

External wall insulation involves adding a layer of insulation to the outside of an existing wall. This insulation layer is usually covered with a protective coat of render or other cladding material to shield it from the weather. 

External wall insulation is an effective option when cavity wall insulation isn’t an option.  

Insulating your walls from the outside is not less effective either and gives you the same benefits such as minimising heat loss, lower energy costs, increased comfort, and improved weatherproofing and some sound resistance. 

external wall insulation grant

What are the benefits of external wall insulation?

External wall insulation has many advantages, including improving your home’s heat retention and reducing your energy bills. 

Internal space isn’t reduced. 

External wall insulation is one of two insulation options for homes with solid walls. The other is internal wall insulation. 

The problem with internal wall insulation is that it reduces the floor space in rooms by around 10 cm per wall. This isn’t the case with external wall insulation, since the insulating material is applied to the outside of the home. 

Improved heat retention 

Around 25% to 45% of household heat is lost through poorly insulated walls. Insulating them will reduce heat loss and make your home feel warmer. 

Reduced energy bills 

External wall insulation will improve heat retention in your home, which in turn reduces your energy bills because when less heat escapes from your home. Because of this your heating system doesn’t have to work as hard to get to the right temperature. 

External wall insulation can save households up to £410 per year on energy bills, according to the Energy Saving Trust. 

Easier installation 

External wall insulation, unlike other forms of insulation such as spray foam insulation, internal wall insulation or floor insulation, causes minimal disruption when being installed. 

Everything is on the outside of a house, not inside so you can still use all the rooms in the house as normal during the installation process. 

Less risk of condensation forming on internal walls 

Condensation on internal walls is caused by the difference in temperature between the cold external air and the warmer internal air. This same principle applies to condensation on windows. 

External wall insulation is a barrier between the inner wall and the external wall that’s exposed to cold air. This reduces the likelihood of condensation forming on the internal wall. 

extenal wall insulation

What are the  factors affecting the cost of external wall insulation? 

The cost of external wall insulation depends on a few things. First off, the size and complexity of your home play a big role – bigger and trickier jobs mean more materials and labour, which equals higher costs. 

Then there’s the insulation material itself and don’t forget about the finish – fancier finishes like render or brick slips can bump up the cost too. 

Accessibility is another factor. If parts of your home are hard to reach, it might mean extra work and more cost. 

But here’s some good news: there are government schemes like the Energy Company Obligation (ECO) that can help cover some of the costs, so make sure to check if you’re eligible for a grant to cover some or all of the cost before you start any work. 

Not sure where to go? Warma is here to guide you through the grant application process, fill in our quick and easy form and we’ll get things started. 

See if you're eligible for free external wall insulation grant
See if you're eligible for free external wall insulation grant

How much does external wall insulation cost? 

On average, you can expect to spend anywhere from £100 to £250 per square metre covering.  

That’s a wide range so here’s a break down the costs for different insulation materials.  

Expanded Polystyrene (EPS) typically ranges from £120 to £150 per square metre, while Mineral Wool tends to be a bit pricier at £140 to £160 per square metre. If you opt for Wood Fibre Insulation, it’s a much cheaper option at around £19 per square metre for the boards alone. 

In general, the total cost of external wall insulation in the UK falls between £7,000 and £15,000. For example, a small flat might cost around £8,000, while a larger property could run up to approximately £22,000. 

According to the Energy Saving Trust, the average installation cost for external wall insulation on a three-bedroom semi-detached home is about £10,000.  

Hopefully these estimates provide you with a rough idea of what to anticipate when considering external wall insulation. 

Keep in mind that these figures are ballpark averages, and your actual costs may vary depending on your specific requirements. 

external wall insulation

So, how much can you save by insulating your exterior walls? 

Well, quite a lot! Installing external wall insulation in the UK can put some serious extra cash back in your pocket when it comes to energy bills. 

External wall insulation is a real winner when it comes to savings. On average, homeowners can expect to pocket between £115 and £360 each year. And if you’ve got a particularly energy-efficient setup, you might even see savings of up to £620 annually. 

So, not only are you saving money, but you’re also doing your part for the planet by making your home more energy-efficient. It’s a win-win! 

Grant for external wall insulation in the UK 

In the UK, homeowners, landlords, and tenants have access to various grants and funding schemes to help cover the costs of external wall insulation. To qualify for a grant, you typically need to meet specific criteria, such as having an Energy Performance Certificate (EPC) rating of D to G and falling within certain Council Tax bands. 

Grants are available for a range of insulation types, including cavity wall insulation, solid wall insulation (internal or external), loft insulation, roof insulation, underfloor insulation, solid floor insulation, park home insulation, and room-in-roof insulation. 

Grants are available from various schemes like the Great British Insulation Scheme and the Energy Company Obligation (ECO) scheme. These programs aim to make energy-efficient upgrades more accessible and affordable and in many cases, FREE for homeowners across the UK. 

Apply for insulation grants with Warma UK 

Warma UK provides free insulation, heating and solar panel grants in the UK through several government-backed home upgrade schemes. 

We’re your go-to for navigating the maze of funding options. We’re experts at helping homeowners access free funding opportunities, so you don’t have to stress about footing the bill.  

With Warma UK on your side, you’ll breeze through the application process for initiatives like the Energy Company Obligation (ECO) Scheme and Great British Insulation Scheme.  

Say goodbye to high energy bills and hello to a brighter, more sustainable future with Warma UK! 

See if you're eligible for free external wall insulation grant
See if you're eligible for free external wall insulation grant

Athira Harish