What Is Cavity Wall Insulation?
Written by: Energy Efficient You
Published: 9th September 2024
An Introduction To Cavity Wall Insulation
Cavity wall insulation is a great way of improving the energy efficiency of your home, reducing heat loss and lowering your energy bills. With the rising costs of energy bills, it should be a priority for all homeowners to look into effective ways to improve their energy usage, and cavity wall insulation can play a massive part in preventing heat from escaping through the walls of your home.
In this article, we will tell you everything you need to know about cavity wall insulation, including how it works, how much it costs, and why so many people are choosing to insulate their homes to save money. Whether you’re looking to save on your energy bills, or want to make an eco-friendly upgrade to your home, this article will help you know if cavity wall insulation is the right choice for you.
What Is A Cavity Wall?
First, it’s important to understand what a cavity wall is, and where they can be found in your home.
A cavity wall is a type of wall construction that consists of two separate walls with a gap, or ‘cavity’, between them. These two walls are typically made of brick or block, and they are connected by metal ties.
The outer wall (facing the outside of the building) protects the house from external elements, while the inner wall helps to support the structure.
Cavity walls became common in houses built after the 1920s in the UK and other countries, replacing solid wall construction. The gap was originally designed to prevent water penetration, with the goal of keeping moisture out of the interor walls of the home, and improving the building’s resistance to dampness. The cavity also created a barrier that reduced the heat loss from the inside of the house to the outside.
While they provide some insulation on their own, the introduction of cavity wall insulation now allows homeowners to keep their homes warmer by filling the gap with insulating material.
What is Cavity Wall Insulation?
Benefits of Cavity Wall Insulation
Cavity wall insulation has been a popular choice throughout the UK for decades, due to its many benefits. We’ve highlighted a few of the main ones here.
- Energy Efficiency – The improved thermal efficiency of your walls means your heating system doesn’t have to work as hard to keep your home warm.
- Cost Savings – Arguably the most popular benefit of cavity wall insulation is the savings on energy bills. Homeowners see savings of around 15-35% per year on their energy bills after installing cavity wall insulation.
- Enhanced Comfort – Homes with cavity wall insulation are noticeably more comfortable. Insulation helps to create a more stable indoor temperature, preventing rooms from becoming too cold in winter or too hot in summer.
- Increased Property Value – Cavity wall insulation can increase the value of your property should you come to sell your home, as it is a desirable feature for new buyers and can improve your EPC rating.
How Does Cavity Wall Insulation Work?
Cavity wall insulation works by filling the gap between the interior and exterior wall with foam insulation, with the goal of reducing heat transfer between walls.
The foam is injected through a pipe into the walls, through small holes drilled into the exterior wall. The foam insulation then expands, filling the entire space between the two walls, creating a barrier that reduces the flow of heat from the inside to the outside.
The insulation foam works by trapping air within its tight structure. As air is a poor conductor of heat, the insulation prevents a significant amount of heat that can pass through the barrier it has created. This is why cavity wall insulation works in the winter and the summer, as it stops heat entering and exiting.
Once the insulation material has been injected and the gap is filled, the small holes are then filled with concrete to seal the insulation inside, and to ensure it matches the exterior wall’s appearance. The process is normally a quick one, taking just a few hours for the average sized home.
How Much Is Cavity Wall Insulation?
There are a few factors that contribute to the cost of cavity wall insulation in the UK, such as:
- Size of your property
- Type of insulation material used
- Access to property and ease of installation
- Location of property
The average cost of cavity wall insulation in the UK is between £300-£700, depending on the size of your home.
While the initial cost of cavity wall insulation may seem high, it is important to consider the long-term savings. Homeowners can save between £100 to £275 per year on their heating bills, depending on the size of their home and energy usage. This means that the cost of insulation can be recouped within just a few years, making it a cost-effective investment.
However, you could be eligible for free cavity wall insulation under the Great British Insulation Scheme. This scheme is backed by the UK government, to make energy-efficient homes more accessible to the average homeowner.
To check if you are eligible, fill out the form below and a member of our team will be in touch!
How Long Does Cavity Wall Insulation Last?
Cavity wall insulation is designed to be a long term solution to heat loss in your home, meaning that it should last a long time before needing repairs or removals. When installed correctly, cavity wall insulation should last for at least 25 years, and often lasts much longer.
There are a few factors that can influence how long cavity wall insulation lasts for, such as the installation quality, moisture and damp around the property, condition of the walls and the average weather conditions of the area.
Here are some things to look out for if you’re worried about needing cavity wall insulation replacements:
- Drafts or noticable cold spots throughout the house.
- Damp patches or mould growth on interior walls. This can indicate that moisture has penetrated the insulation foam and has entered the cavity.
- Find yourself turning on the heating more often and higher heating bills, without unusually cold weather. This can often show if heat is escaping through the walls again.
Can Cavity Wall Insulation Be Removed?
Yes, cavity wall insulation can be removed, but the process is lengthy and complex. Cavity wall insulation is designed to be a long term solution, and often never needs removing, but there are certain situations where removal may be necessary, such as insulation or property damage.
Removing cavity wall insulation is best handled by the professionals. They have the required equipment and expertise to ensure the removal is done efficiently and safely. Improper removal can lead to further damage to your property.
The cost to remove cavity wall insulation is typically rather expensive, often comparable or exceeding the cost of installation, due to the complex nature of the removal.
While cavity wall insulation can be removed, it is usually considered a last resort. If you are experiencing issues with your current insulation, consult with a professional to determine the best course of action and ensure any problems are properly addressed before making decisions about removal or replacement.
Is Cavity Wall Insulation Safe?
Yes, cavity wall insulation is generally considered safe when installed by professionals and monitored for issues. Like any home improvement, there are always some considerations to ensure safety:
- Proper installation – Do not attempt to install cavity wall insulation yourself. It is a complex practice that is best left to professionals, who ensure that the insulation is properly and safely injected into the walls, and complying with industry regulations. Improper installation can result in costly damage to the property.
- Moisture and Damp Issues – The main concern is if moisture becomes trapped between the cavity. if not properly addressed, this can lead to long term damp problems and mould growth on interior walls. This is why it is crucial to consult a professional, as they will conduct an assessment prior to installing cavity wall insulation to ensure that the home has sound, dry walls, and see whether any existing damp issues can be solved before installation.
- Maintenance: Regular maintenance of the property, including checking for signs of dampness or damage, helps ensure the insulation remains effective and safe. Addressing any issues promptly can prevent more significant problems.
Is Cavity Wall Insulation Worth It?
Cavity wall insulation can be a highly effecting investment for many homeowners in the UK looking to improve the energy efficiency of their home. Cavity wall insulation has several benefits, such as:
- Energy Savings: One of the most compelling reasons to invest in cavity wall insulation is the potential for significant savings on energy bills.
- Return on Investment (ROI): The cost of installation is generally recouped through these savings within a few years. Over the lifespan of the insulation, the cumulative savings on energy bills can make it a cost-effective upgrade.
- Improved Indoor Climate: Cavity wall insulation contributes to a more stable indoor temperature, reducing drafts and cold spots. This enhanced comfort can make your home more enjoyable and livable year-round.
- Reduced Condensation: Proper insulation helps to minimise condensation and the risk of mould, contributing to a healthier indoor environment.
- Reduced Carbon Footprint: By improving your home’s energy efficiency, cavity wall insulation helps to lower your carbon footprint.
- Attractive Feature for Buyers: Homes with cavity wall insulation are often more attractive to buyers due to the potential for lower energy bills and improved comfort. This can enhance the market value of your property.
There are also things to consider before deciding whether cavity wall insulation is the right choice for you, such as:
- Initial Costs: While the initial cost of installation can be a consideration, it is typically offset by long-term savings.
- Maintenance and Longevity: Properly installed cavity wall insulation is designed to last for decades. However, it’s essential to ensure that any existing moisture or damp issues are addressed before installation to avoid future problems.
To ensure that cavity wall insulation is effective and worthwhile, it’s crucial to have it installed by a reputable professional. Proper installation addresses any potential issues and maximises the benefits. In conclusion, cavity wall insulation is often worth the investment for most homeowners. It offers substantial financial savings, improves comfort, supports environmental sustainability, and can enhance property value.
You may also be eligible for free cavity wall insulation if you meet the requirements for The Great British Insulation Scheme. Check your eligibility for free down below!
Apply For A Cavity Wall Insulation Grant
Apply for a cavity wall insulation grant today by filling out our quick eligibility form below. Once you have filled out the form, a member of our team will be in touch with you to discuss the next steps.
See Our Other Blogs
How Much Does External Wall Insulation Cost?
External Wall Insulation has become a popular choice for homeowners to improve energy efficiency and reduce heating costs. Also referred to as solid wall insulation, it involves adding a layer of insulation material to the exterior walls of the building. This then acts like a thermal barrier, reducing heat loss through the walls. External wall insulation is key to lowering your energy bills.
How To Calculate Energy Efficiency
Energy efficiency is a measure of how effectively energy is utilised in a system or process to accomplish a specific task. It’s about getting the most out of the energy we use and optimising performance. Whether it’s in homes or businesses, understanding and improving energy efficiency are steps toward sustainability and resource conservation.
Solar PV has gained immense popularity as a clean and reliable energy source that holds the promise of reducing greenhouse gas emissions and minimising our dependence on fossil fuels. Photovoltaics (PV) has transformed the way we produce and consume electricity. Learn more about how solar pv can help save you money on your electricty bills.
