Cavity wall insulation is an essential consideration if you’re looking to improve energy efficiency, reduce heating bills, and increase the comfort of your home.
In this article, we’ll explore what is cavity wall insulation, its benefits, costs, potential problems, and even how to remove it if necessary. We’ll also look into grants and options for getting free cavity wall insulation, making the investment more affordable for many households.
What is Cavity Wall Insulation?
Cavity wall insulation is a process where insulating material is injected into the gap (or cavity) between the inner and outer walls of a building.
Houses built in the UK after the 1920s typically have cavity walls, where two layers of brick or concrete blocks are separated by an air gap.
This design was intended to prevent moisture from penetrating the inner walls, but it also allows heat to escape.
Cavity wall insulation materials
By filling this cavity with insulation material, homeowners can significantly reduce heat loss, which leads to a warmer home and lower energy bills.
Benefits of Cavity Wall Insulation
Installing it offers numerous advantages for both you and the environment:
Energy Efficiency
It helps retain heat, meaning your home will stay warmer in the winter and cooler in the summer. This reduces the need for constant heating or cooling, which directly lowers energy consumption.
Lower Energy Bills
Because your home becomes more energy-efficient, you’ll spend less on heating. Homeowners can typically save hundreds of pounds annually on their energy bills.
Reduced Carbon Footprint
Reducing your home’s energy usage not only saves money but also helps lower your carbon footprint, making your home more environmentally friendly.
Increased Property Value
Homes with good energy ratings are more attractive to potential buyers, and having it can improve your home’s Energy Performance Certificate (EPC) rating.
How Much Does Cavity Wall Insulation Cost?
One of the key considerations for homeowners is how much is cavity wall insulation and what factors influence the price.
The cost of cavity wall insulation varies
Prices typically come down to four major considerations. Let’s explore what these are:
Size of Your Home
The bigger the house, the more cavity wall insulation material is required. Larger homes, particularly those with multiple stories, will naturally incur higher costs.
Type of Insulation Material
Different insulation materials have varying costs. For example, mineral wool tends to be cheap, but other alternatives may offer superior insulation properties.
Installation Costs
Installation prices can vary depending on your location and the contractor you hire. It’s important to get multiple quotes to ensure you’re getting the best deal.
Grants and Subsidies
Many homeowners are eligible for government cavity wall insulation grants or schemes that significantly reduce or even cover the entire cost of installation (more on this below).
Cavity Wall Insulation Grants: How to Get Free Insulation
The cost of installing it may be a concern to you, but there are options available to help reduce this financial burden.
Various government initiatives offer cavity wall insulation grants, sometimes making it possible to get free cavity wall insulation.
You can check out the gov website for a number of schemes and grants, but let’s run through some of the main ones…
Energy Company Obligation (ECO) Scheme
The UK government’s ECO scheme is designed to help low-income households and those at risk of fuel poverty.
Through this program, energy companies are obligated to provide funding for energy efficiency improvements, including cavity wall insulation, often at no cost to the homeowner.
Great British Insulation Scheme
You can apply for this on the official government website. You have a chance if your home has:
- Energy performance certificate (EPC) of D to G
- Council Tax bands A-D in England or A-E in Scotland or Wales
You don’t need to be a homeowner to apply, but always check with your landlord if you are a tenant.
(The Great British Energy Scheme is not available in Northern Ireland)
Local Authority Grants
Some local councils offer additional grants or funding to make homes more energy-efficient.
These grants can be available to anyone or targeted towards specific groups such as pensioners, low-income families, or people with disabilities.
Eligibility for Grants
To qualify for free cavity wall insulation, you may need to meet certain criteria, such as being on specific benefits or living in a property that is considered hard-to-insulate.
It’s worth checking with your local council or energy provider to see if you’re eligible for assistance.
Cavity Wall Insulation Problems
While it can offer many benefits, there are also potential cavity wall insulation problems you should be aware of.
What to look out for: problems and issues
Moisture Penetration
In certain cases, especially if the insulation is poorly installed or if the home is in an area prone to wind-driven rain, moisture can seep into the cavity, leading to dampness inside the house. This is particularly problematic in homes with damaged brickwork or mortar.
Inappropriate Property Type:
Cavity wall insulation is not suitable for every property. Homes located in areas with high rainfall or that have solid walls (instead of cavity walls) may not benefit from insulation and could suffer from damp problems if installed improperly.
Settlement of Insulation Material:
Over time, some insulation materials, particularly older ones, may settle or degrade, reducing their effectiveness. This can lead to cold spots within the home.
Hard to Remove:
Once installed, it can be difficult and costly to remove, so it’s important to ensure it’s suitable for your home before proceeding.
How Long Does Cavity Wall Insulation Last?
One of the most common questions homeowners ask is, how long does cavity wall insulation last? In general, it’s designed to be a long-term solution and can last for the lifetime of your home (often 25 years or more) without needing replacement.
However, the longevity of the insulation depends on several factors:
- Type of Insulation Material: Higher-quality materials tend to last longer than older materials like mineral wool.
- Installation Quality: Poor installation can lead to gaps or sagging of the insulation over time, reducing its effectiveness.
- Maintenance of the Property: Keeping your home’s brickwork and mortar in good condition helps protect the insulation from moisture and other external factors that could shorten its lifespan.
How to Remove Cavity Wall Insulation
While it is usually a permanent addition to your home, there are circumstances where removal might be necessary.
This may be due to cavity wall insulation problems such as dampness, faulty installation, or the insulation material degrading over time.
Also, you may have inherited problems or issues from previous owners.
Guide on how to remove cavity wall insulation:
- Hire a Professional: Removing cavity wall insulation is NOT a DIY project.
It requires specialised equipment to extract the insulation from the cavity. Professionals will drill small holes into the mortar joints and use an industrial vacuum to suck out the insulation material.
- Cost of Removal:The cost of removing it can vary depending on the size of the house and the type of insulation used. It is typically more expensive than installation due to the complexity of the process.
- When Removal is Necessary:If you’re experiencing issues like damp walls or if you’ve been advised by a professional that your home is not suitable for it, removal may be the best option. After removal, it’s important to address any underlying structural problems before considering reinstallation.
How to Install Cavity Wall Insulation
Installing cavity wall insulation is a specialised job that requires the right tools and expertise.
The installation is typically handled by professionals, which we would advise to make sure it’s done to the highest standard.
Here’s a step-by-step look at how cavity wall insulation might be installed by injecting insulation materials.
Surveying the Property
Before any insulation can be installed, a professional installer will conduct a survey of your property. This inspection helps to determine whether your home is suitable.
The surveyor will check the age of the property, the width of the walls, and the condition of the brickwork and mortar.
Properties with significant cracks or damaged brickwork may need repairs before insulation can be applied to prevent moisture issues later on.
The survey will also identify the type of insulation material best suited for your home, whether that’s mineral wool, polystyrene beads, or other alternatives.
Drilling Holes in the External Walls
Once the property has been deemed suitable, the installation process begins by drilling small holes into the external walls.
These holes, usually about 22mm in diameter, are spaced at regular intervals to ensure even distribution of the insulation.
The installer typically drills into the mortar between the bricks rather than the bricks themselves, which minimises damage to the structure and makes it easier to patch up after installation.
Holes are drilled on all sides of the house that have cavity walls, as well as above and below windows to ensure the insulation fills the entire cavity.
Injecting the Insulation Material
After the holes are drilled, the insulation material is injected into the cavity using specialised equipment.
For example, mineral wool and polystyrene beads are typically blown into the cavity using a high-pressure hose.
The installer monitors the process carefully to ensure the insulation fills the entire cavity evenly, preventing gaps or cold spots from forming.
The process is quick and efficient, with most houses fully insulated in just a few hours.
Sealing the Drilled Holes
Once the insulation is in place, the installer will seal up the drilled holes using mortar that matches the existing brickwork. This ensures the exterior of your home looks the same as it did before installation, with no visible signs of the work done.
Proper sealing is also important to protect the walls from moisture and weathering.
Final Inspection
After the holes are sealed, a final inspection is carried out to ensure the installation has been done properly. The installer will check that all areas of the cavity have been filled and that the walls show no signs of damage or other issues.
At this stage, they may also provide advice on how to maintain the insulation and address any potential future concerns, such as condensation or dampness.
Post-Installation Considerations
Once the installation is complete, it’s important to ensure the brickwork and external walls are well maintained to avoid moisture penetration.
Homeowners should monitor their walls, particularly in areas exposed to heavy rain, to ensure that cracks or damage to the brickwork do not compromise the insulation. Proper ventilation in your home is also crucial, as it helps to regulate indoor moisture levels and prevent condensation on windows buildup.
Cavity Wall Insulation: Conclusion
Cavity wall insulation is a valuable investment for homeowners looking to improve the energy efficiency and comfort of their homes.
By understanding the benefits, costs, potential problems, and available grants, you can make an informed decision about whether it is right for your property.
Whether you’re looking to reduce your energy bills or minimise your carbon footprint, in the right circumstances it can offer a practical and effective solution.
Before jumping right in make sure your home is suitable (ask a professional), to avoid potential issues. If you’re eligible for cavity wall insulation grants, you may even be able to install it at no cost, further enhancing the value of this energy-saving upgrade.
If you’d like any further information, feel free to reach out and ask!
