Cavity Wall Insulation
Save hundreds on your heating bills with effective cavity wall insulation from SEF. Our energy efficient industry leading insulation solutions are perfect for properties, whether adding insulation to unfilled cavity walls for the first time or upgrading your existing insulation.
What is Cavity Wall Insulation?
Cavity wall insulation involves filling the gap (or cavity) between the inner and outer walls of your property with a thermal barrier to reduce heat loss. It is suitable for properties with a cavity space of at least 40mm between bricks.
This type of insulation helps maintain a comfortable temperature inside your home, saving on energy bills while ensuring your home stays warmer in winter and cooler in summer.
The Key Benefits of
Cavity Wall Insulation
Cost-Effective
Filling cavity walls is one of the most affordable methods for improving energy efficiency.
Lower Energy Bills
By preventing heat loss (by as much as 33%), you’ll use less energy so insulation can have a big impact in lowering your energy bills.
Better Comfort
Your home will feel far more comfortable year-round without the need to have your heating on for prolonged periods.
Soundproofing
Cavity wall insulation can help reduce external noise, creating a quieter and more peaceful home environment.
Environmental benefits
A more energy efficient home contributes to a greener environment by reducing your carbon emissions
Long-lasting Performance
Our cavity wall insulation solutions are durable and should last for several decades.
Why Choose SEF Ltd for Your Cavity Wall Insulation?
At SEF, we specialise in professional cavity wall insulation installation. We use the high quality ThermaBead insulation products and install these to the highest standards, to ensure maximum energy efficiency, savings and comfort for our customers.
Whether you’re building a new property or upgrading an existing one, we offer tailored cavity wall insulation solutions to meet your needs. We’re committed to providing you with an easy installation process and outcome that ensures your home is energy-efficient and cost-effective for years to come.
Using Industry Best ThermaBead
Cavity Wall Insulation
We use industry leading ThermaBead insulation to fill the cavity walls in properties and drastically reduce the amount of heat passing through the wall. ThermaBead system is a grey bonded-bead system that is pressure blown into the cavity using a special injection gun.
Quick installation
In most cases can be installed within a few hours with minimal disruption
Safe
ThermaBead bonding agent is a water-based dispersion of acrylic co-polymer emulsion, white in appearance and is non-hazardous.
Fire safe
Fully fire resistant in its installed state, and with full BBA and KIWA approval.
Long-lasting
The beads have been thoroughly tested and will not deteriorate over time.
Durable
Not affected by any improvement works such as fitting new double glazing.
Meets building regulations
ThermaBead fully satisfies the latest required standards for energy efficiency.
Cavity wall installation process
what to expect
Step 1
One of our team will visit to survey your property and establish your need for cavity wall insulation. An installation date will be agreed with you.
Step 2
Preparation, including securing or removing all loose items or cutting back any plant growth, will be carried out if necessary.
Step 3
Small holes will be drilled into external walls at key points, in line with BBA and KIWA specifications.
Step 4
ThermBead insulation will be blown into the wall cavities using specialised hose equipment.
Step 5
All holes are filled to be barely visible and the site will be cleaned and all items returned to the original location.
Step 6
Final inspection of your installation is made to ensure all is in good order.
Cavity Wall Insulation Extraction
We also specialise in the removal of old or failed cavity wall insulation, including materials such as UFFI and blown fibre that may have degraded over time or lost their effectiveness.
Using specialised cavity wall extraction equipment, we safely remove insulation by creating controlled access points in the wall and applying powerful vacuum suction. Compressed air is used to loosen and direct the material towards the extraction system, ensuring the cavity is thoroughly cleared with minimal disruption to the property.
This process allows us to prepare your walls for modern, high-performance insulation, improving efficiency and long-term protection.
Frequently Asked Questions
If cavity wall insulation is being added to a property retrospectively (as opposed to being added to a new build), then a series of drill holes are made in the outside walls and ThermaBead insulation material is pumped into the cavity space. The holes are resealed to match the existing brick work so you’ll barely know they were there.
Cavity wall installation is usually pretty straightforward when there are easily accessible walls, and for a typical 3-bedroom semi-detached property would take around 3 hours, but this will depend on the size of the property. Note, cavity wall insulation should only be carried out by registered professional installers.
It is relatively straightforward to establish whether you have cavity wall space in your property. A home with cavity walls will usually have brickwork with an even pattern, with all the brick laid lengthways. These can be viewed from your external walls.
With solid walled properties (which don’t have cavity spaces to fill), the bricks will be laid in an alternating pattern, with some bricks laid in such a way that some of the smaller ends of the bricks can be viewed from the outside walls. Most houses built since the 1930s are likely to have cavity wall space that can be filled with insulation.
If your home is not suitable for cavity wall insulation, then internal solid wall insulation or external insulation are good options.
While both mineral wool and spray foam are effective insulations in some contexts, they are not the best choice for cavity wall insulation and that’s why we use the ThermaBead system. It is a highly effective insulation method using polystyrene beads that last for many years to come.
In most circumstances, where your cavity wall insulation has failed, we would recommend you have it removed. In the case of spray foam removal, the insulation would be broken up with specialist equipment and then vacuumed up so that the cavities can be replaced with more effective insulation. We can help you with the spray foam removal as well as cavity wall insulation replacement.