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September 27, 2023

How Does Cavity Wall Insulation Work?

How much does Loft Insulation cost?

In a time where energy efficiency and sustainability take centre stage, many homeowners are seeking ways to make their homes more energy efficient and reduce their carbon footprint. One effective solution gaining popularity is cavity wall insulation

Cavity wall insulation works by reducing heat loss through a cavity wall by filling the air space with material that stops heat transfer. This captures the air within the cavity preventing heat loss and resulting in reduced energy costs. This insulation process can be performed on both new and existing homes, making it a versatile solution for a range of housing types.

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The Process of Cavity Wall Insulation

Cavity wall insulation involves filling cavity walls with insulating material which acts as a barrier, preventing thermal energy from escaping through the walls. This is how the installation process unfolds.

  1. Preparation

Before insulation, a thorough assessment of the property is necessary. This includes checking the suitability of the walls, their construction, and the presence of any pre-existing insulation. 

  1. Drilling 

Small holes, typically no larger than a penny, are drilled into the external wall at consistent intervals. These holes serve as entry points, enabling the controlled injection of the insulating material into the wall’s cavity.

  1. Insulation Injection

Through the drilled holes, insulating material is introduced into the cavity. The material can vary and may include mineral wool, foam, or polystyrene beads. This material forms a continuous barrier, hindering the movement of heat.

  1. Cavity Sealing

Once the insulation material is in place, the holes are sealed using mortar or a similar substance to match the wall’s appearance.

Why You Should Install Cavity Wall Insulation

In the search for a more energy-efficient and sustainable living environment, the installation of cavity wall insulation is a popular choice for homeowners. This innovative solution offers many benefits when it comes to its installation.

Enhanced Energy Efficiency 

Cavity wall insulation works by introducing insulating material into the cavity between walls, which reduces heat transfer. This process captures the air within the cavity, preventing heat loss and resulting in reduced heating costs. Statistics highlight that the estimated lifetime energy savings reached a staggering 224,400 GWh by March 2022 with cavity wall insulation accounting towards these savings by 43%.

Lasting Comfort

Cavity wall insulation not only impacts your heating bills but also enhances your daily living experience. The consistent temperature regulation created by this insulation leads to a more comfortable living environment throughout the year. Say goodbye to chilly drafts in the winter and stifling heat in the summer with cavity wall insulation.

Noise Reduction

Beyond temperature control, cavity wall insulation contributes to sound insulation. The added layer of insulation dampens external noise, creating a quieter and more serene living space. Whether you live in a bustling urban area or a peaceful suburban neighbourhood, this added benefit ensures your home remains an oasis of tranquillity.

Environmental Responsibility

Insulating your walls is a good place to start, as the energy saving trust states that around a third of the heat lost from an uninsulated home escapes through the walls. At a time when environmental consciousness is crucial, cavity wall insulation enables you to directly contribute to reducing your carbon footprint by 1100kg Co2 a year.


By consuming less energy to regulate indoor temperatures, you actively decrease the demand for fossil fuels, effectively reducing harmful greenhouse gas emissions. Installing cavity wall insulation transcends being a mere home improvement, it’s a definitive stride towards a greener, more sustainable future.

Improved Home Value

Investing in cavity wall insulation boosts your property’s value significantly. In today’s market, energy efficiency matters to buyers. A well-insulated home stands out, offering potential savings and comfort.

Not having cavity wall insulation or other types like loft or external insulation, can impact your property’s appeal. Buyers often seek insulated homes and might offer less if they see insulation as a future cost. Insulation isn’t just about comfort, it affects your property’s value and marketability.

Low Maintenance

Once cavity wall insulation is installed it requires minimal upkeep. Unlike some home improvements that demand regular attention, this insulation method quietly goes about its job without the need for ongoing maintenance. This frees up your time and resources for other pursuits.

Financial Initiatives

Governments and local authorities offer financial incentives and grants such as the Eco Scheme and the Great British Insulation Scheme to encourage homeowners to invest in energy-efficient improvements, including cavity wall insulation. 


The newly introduced Great British Insulation Scheme is set to launch summer 2023 and continue until March 2026. This government initiative offers financial support for cavity wall insulation and other measures to insulate homes, enhance energy efficiency, and reduce energy bills. These incentives can significantly offset the initial installation costs, making the decision to insulate your walls even more attractive.

Does Cavity Wall Insulation Really Work?

Insulating cavity walls operate on the simple yet powerful principle of reducing heat transfer through walls. By introducing insulating material into the cavity, this technique effectively minimises heat loss during colder months and heat penetration during warmer periods. This approach has many benefits and can save up to £680 annually on energy bills for a 3-bedroom house.

With its positive impact on energy efficiency, energy savings, and overall comfort, cavity wall insulation stands as a practical and economical choice for homeowners looking to create more eco-friendly and comfortable living spaces.

Professional Cavity Wall Insulation at Effective Home

At Effective Home, we provide comprehensive cavity wall insulation services that begin with a free home energy survey. Our installation process is designed for your convenience, complemented by flexible payment options. 

Our team of registered installers guarantee a seamless experience, minimising any potential disruptions and leaving your home in a clean and orderly state. With 30 years of experience, we back our services with a 25-year insulation guarantee. 

Get a quote today

Get your free insulation quote
How much could I save?

Get your free insulation quote

Justine Effective
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