Did you know that around one-third of the heat loss from most homes is through the walls? That’s a lot of heat loss. What’s more, it’s heat loss that householders can prevent.

By insulating your cavity walls, you can not only save up to £485* per year on your energy bills, but you will also benefit from a warmer home in the colder months.

These aren’t the only benefits. By ensuring your cavity walls are adequately insulated, you are playing your part in helping to reduce carbon emissions, while improving the energy performance rating of your home.

 

Approved materials to insulate householder’s cavity walls

What material is used to insulate cavity walls? Commonly used materials include blown mineral wool fibre or bead cavity wall insulation. Both systems have been tested, assessed, and approved by industry bodies such as the British Board of Agrement and KIWA.

Up to 20% more efficient than standard fibre insulation, bead cavity wall insulation is a grey bonded-bead system that is pressure blown into the cavity in your walls by a specially designed injection gun. The material acts like a tea cosy surrounding your home, trapping the heat, and keeping your house cosy and warm.

Dyson Energy Services, a leading national installer of insulation and other energy-saving measures, predominantly installs bead cavity wall insulation to homes across the country.

 

Expert advice from a leading manufacturer of bead cavity wall insulation

To help answer some of your questions, we’ve invited a representative from a leading manufacturer of bead cavity wall insulation, ThermaBead, to give expert advice on the features and benefits of bead cavity wall insulation, otherwise known as expanded polystyrene beads.

Meet Jeff Harris. Jeff is the Technical Manager at ThermaBead and has over 25 years experience in the insulation retrofit industry, so is well placed to answer some commonly asked questions on their bead product, ThermaBead Carbon Saver, that Dyson Energy Services install into 1000s of homes each year.

 

 

Does bead cavity wall insulation work and how effective is it? Read the Q&A with Jeff, to find out.

 

Q: Tell us about the ThermaBead Carbon Saver product

Much like the beads in a bean bag, ThermaBead Carbon Saver is Polystyrene. However, it is made with Carbon or Graphite which gives it it’s grey or silver colour. This addition reflects more of the heat making it far more efficient as an insulation material.

When it arrives at the processing plant it is hard tiny beads. These beads have pentane gas trapped inside and pentane expands when heated, so the material is put through expanding machinery. This mixes the beads with steam and air, increasing the beads by up to 60 times its original size.

The speed of expansion is carefully controlled to end up with beads with a known specific density. To achieve the best insulation possible the bead is processed twice before being loaded onto trailers for distribution, ready to be installed into cavity walls.

 

Q: Tell us about some of the benefits of bead cavity wall insulation

Ease of Installation

ThermaBead Carbon Saver is typically injected into the cavity wall through 22mm holes, approximately the size of a 10p piece, drilled through the mortar joints. Far fewer holes are required than with other insulation systems and the process is quite quick and painless. A typical semi-detached house can be insulated within a few hours and the benefits are immediate.

 

Flowability

Being lightweight round beads, ThermaBead Carbon Saver has an incredible ability to fully fill the cavity leaving no gaps or voids. When injected it flows like a thick liquid into every space where the adhesive dries leaving a stable homogenous product. It’s the remarkable free flowing nature that means less injection holes are needed.

 

Moisture dissipation

Every product used to insulate cavity walls has to endure a three-week water permeability test. This is to replicate wind driven rain against a brick-built cavity wall. As the test progresses the air pressure and water spray increase to storm conditions.

Bead cavity wall insulation still allows the cavity to work as intended rather than creating a physical barrier. Water can still enter the cavity, but rapidly flows through the beads to the bottom of the wall. It does this through the tiny spaces between each of the round beads. Householders should be reassured is that the bead system doesn’t rely on water repellent additives, which can break down over time.

ThermaBead Carbon Saver:

• Reduces heat loss rates of around 70%

• Doesn’t absorb water, so no risk of rising damp or damp walls

• It is an excellent free flowing material, so cavity walls are evenly insulated – avoiding cold bridging and localised condensation related damp.

• It doesn’t break down and therefore is an effective insulant for the lifetime of your home.

 

Check out this video on the benefits of bead cavity wall insulation.

 

Q: Is bead cavity wall insulation tested and approved?

ThermaBead Carbon Saver has undergone lots of testing and still does to ensure consistency.
We have worked with the BBA, BRE as well as Salford university and other organisations, testing for full fill, water transmittance, thermal performance, and other criteria.

Due to the unique way in which ThermaBead Carbon Saver still allows the cavity to work as intended and the rigorous testing carried out, there is no exposure limit, allowing suitable properties to be insulated even in areas of extreme weather.

 

Q: Is it environmentally friendly?

Bead cavity wall insulation is Polystyrene, uh oh! That’s a plastic, however it isn’t the environmental arch enemy like single use plastics that our planet is suffering from. The advantage is that being a plastic it doesn’t break down or absorb water, therefore once installed it remains effective for the life of the building.

A percentage of the raw bead is actually made up of recycled plastic and as technology advances the percentage will increase, not only that, but the expanded polystyrene beads can also be recycled into other products when the time comes.

Because of its longevity and amazing thermal performance any perceived negatives are far outweighed by the energy savings achieved when insulating with ThermaBead Carbon Saver.

 

Q: Does your bead cavity wall insulation product meet the latest building regulations?

ThermaBead Carbon Saver is an excellent Insulation material which not only meets but exceeds current building regulations, which is fast becoming the cavity wall insulation of choice for existing homes and new homes being constructed.

 

 

 

Peace of mind with a 25-year CIGA guarantee

After having cavity wall insulation installed, every householder will receive a 25-year industry backed IAA guarantee for peace of mind (Installation Assurance Authority).  The IAA is an independent body that provides consumer protection by means of a guarantee for cavity wall insulation fitted by registered installers in the UK.

 

Funding available for free cavity wall insulation in 2024

For those looking online in 2024 for information about insulation funding, it is available for households in Council Tax Bands A – D.  The Connected for Warmth Scheme, funded by the National Grid, offers eligible householders fully funded cavity wall insulation, as well as loft-insulation to owner-occupiers, private tenants and private landlords.

Find out further information about free cavity wall insulation.

 

“Since having cavity wall insulation, our home is much warmer in the winter and cooler in the summer”

Neil and Karen, a couple from Somerset, benefitted from the bead cavity wall and loft insulation installed. It was fully funded through the Energy Company Obligation scheme and installed by Dyson Energy Services.

Neil said, “We have to do our bit for future generations, especially with what is going on with climate change. We are much warmer; we’ve reduced our carbon footprint and our energy bills.”

Read their story.

 

Why choose Dyson Energy Services to insulate your cavity walls?

We have been installing energy-saving measures for over 40 years. Over the past four decades, we’ve grown into a nationally recognised installer – with over 3 million energy-saving measures delivered across insulation, renewables, and renewables.

We’re proudly reducing householder’s carbon emissions and energy bills, as well as playing our part in helping to tackle fuel poverty in your communities.

• TrustMark registered – delivering confidence, comfort, and choice through Government endorsed quality
• All our experienced Insulation Installers are employed by us
• Work with industry-leading manufacturers, like ThermaBead, to deliver and install sustainable energy-saving insulation, into homes across the country.

 

 

*According to the Energy Saving Trust (EST). Estimates based on a gas-heated home – detached house.  Figures based on fuel prices January 2024.