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Cavity wall insulation

Make your home warmer and cheaper to heat

JJ Crump Wal Insulation Installer

Save money on your heating bills

Up to a third of heat is lost through the walls of uninsulated properties. Act now and have your walls insulated to save energy and cut your heating bills.

If your house was built after the 1920s, it is likely to have cavity walls.  A cavity wall is made up of two walls with a gap in between, known as the cavity; the outer leaf is usually made of brick and the inner layer of brick or concrete block.

Pre-1920 older houses are more likely to have solid walls. A solid wall has no cavity; each wall is a single solid wall, usually made of brick or stone.

But don’t worry, our surveyor will be able to advise you whether your home is suitable for cavity wall insulation when he calls at your home.

Many cavity walls can be insulated but filling cavity walls is not a job you can do yourself, you will need a registered installer to carry out the work.

The process is very simple and the team at J&J Crump and Son will:

  • Drill small holes, around 22mm in size, in the outside walls at intervals of 1m.
  • The installer then blows insulation, which is usually mineral wool or polystyrene beads, into the cavity using special equipment.
  • Once all the insulation is in, the installer fills the holes in the brickwork with cement so you’ll barely notice them.
  • The whole process will take around two hours for an average house with easily accessible walls and it shouldn’t make any mess.
  • You will be given a 25-year guarantee after the work is completed.

Do I need insulation?

Why have cavity wall insulation?

Installing insulation is like wrapping your home in a big comfy quilt. The insulation acts to stop the heat escaping straight through your walls meaning your home stays warmer longer and the heating system doesn’t have to work as hard saving you money on your bills.


Do I need cavity wall insulation?

It’s possible that your property may not be suitable for cavity wall insulation and sometimes this can be identified by the homeowner. This can be done by identifying your wall type by looking at the pattern of the bricks.

Cavity wall insulation materials

For most people, we recommend installing ‘bead’ materials, which is made of very small polystyrene balls.

The product has been developed and refined over many years to satisfy the ever-increasing demand for better, warmer, more energy-efficient housing and it outperforms all other methods of insulating cavity walls.

The fuel bill is a major expense which increases year after year. Installing Carbon Bead will dramatically cut the heat loss through the walls and actually make them feel warmer. The rooms will have uniform temperature which will increase without turning up the heating and the building will retain its warmth longer after the heating is turned off.

We do in some cases install ‘blown fibre’ which is mineral wool where this is the best option. Our surveyor will discuss with you which product is most suitable for your home, leaving you to make an informed choice.

Properties of Carbon Bead

Carbon Bead has been developed and refined over many years and has been rigorously tested by the British Board of Agreement and received their certificate of approval for use in all exposure zones.

Carbon Bead is completely safe to use with NO DANGEROUS FUMES, NO HARMFUL FIBRES TO INHALE and there is NO RISK OF SETTLEMENT taking place after installation and furthermore in the opinion of BRE the materials should prove an acceptable insulation as a precaution against Radon in a new build.

Thermal properties

The product has a declared thermal conductivities of 0.033 W·m–1·K–1 for InstaBead Carbon Saver.

Water penetration

The product will resist the transfer of water across the cavity to the inner leaf.


The product will contribute to limit the risk of condensation.

Behaviour in relation to fire

Use of the products does not prejudice the fire resistance properties of the wall.


The product is durable, rot-proof, water-resistant and sufficiently stable to remain effective as an insulation for the life of the building.

Why choose Carbon Bead?

  • It is a high performance insulation
  • It's free flowing and fills every inch to a uniform density
  • The beads are bonded together to ensure permanent stability
  • It maintains the function of the cavity wall by allowing water to drain away naturally
  • Installation is quick with no mess and no fuss
  • There are various cavity wall insulations materials currently available, but for performance, safety and durability few can match the InstaFibre Carbon Saver Plus

Read the bead datasheet

Why not get a FREE, no obligation estimate?

Insulating your property is one of the key areas to save money on your energy bills and helps to keep your home cosy and warm too.

Why not get a FREE no obligation estimate today?

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