Cavity Wall Insulation

Cavity Wall Insulation

We currently have access to funding your cavity wall insulation. Costing you as little as £99 to make huge savings in your heating bill.

cavity wall insulation

About a third of all the heat lost in an uninsulated home escapes through the walls.

Heat will always flow from a warm area to a cold one. In winter, the colder it is outside, the faster heat from your home will escape into the surrounding air.


In general, houses built from the 1990s onwards have wall insulation to keep the heat in, but if your house is older than that it may not have any wall insulation. If this is the case then you may be heating the outside air, instead of just heating your home.


Most types of wall can be insulated in one way or another. If you have a typical house with cavity walls, you could save up to a third on your heating cost just from insulating the walls.


How to identify a cavity wall

cavity wall vs solid

Houses in the UK mostly have either solid walls or 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.
  • • A solid wall has no cavity; each wall is a single solid wall, usually made of brick or stone. Working out your wall type.

If your house was built after the 1920s, it is likely to have cavity walls. Older houses are more likely to have solid walls. If you can see the brickwork on the outside of the house, look at the pattern of the bricks. If your home has cavity walls, the bricks will usually have a regular pattern whereas a alternating pattern of bricks would indicate a solid wall


If the brickwork has been covered, you can also tell by measuring the width of the wall. Examine a window or door on one of your external walls. If a brick wall is more than 260mm thick then it probably has a cavity; a narrower wall is probably solid. Stone walls may be thicker still but are usually solid.

Non-standard wall types

If your house is a steel-frame or timber-framed building, or is made from pre-fabricated concrete different rules apply for insulation. Generally these houses don't have a cavity to fill, but it may be possible to insulate them in the same way as a solid wall. However, you may need a specialist company to insulate a non-standard wall. For further advice or to find an installer who can help you, contact the National Insulation Association.

What's cavity wall insulation and is it suitable for my home?

cavity wall vs solid

Cavity wall insulation fills gaps often found between external walls in homes built after 1920, keeping the warmth in to save energy. It can also help reduce condensation inside the house if this is a problem stemming from your external walls. It is blown into the cavity from the outside of a house. Every part of the wall must be filled with insulation, so it's important that the installer can reach all your external walls.

Your home will usually be suitable for cavity wall insulation if it meets these criteria:

  • • Its external walls are unfilled cavity walls.
  • • Your cavity is at least 50mm wide.
  • • The masonry or brickwork of your property is in good condition.
  • • It is more than 10 years old (most newer houses will have insulation already).
  • • The walls are not exposed to driving rain.

If you have any damp patches on your internal walls then they should not be insulated until the problem is resolved. Speak to a builder who specialises in damp prevention. If your home's external walls are joined to another house, the installer will need to insert a cavity barrier to contain the insulation so your neighbours aren't affected.

What is cavity wall insulation made from?

Cavity wall insulation can generally be made from three types of material: mineral wool, polystyrene beads, or foamed insulants. All three are manufactured according to British standards. Foam insulation systems should be certified by the British Board of Agrément and installed according to strict guidance laid out in the associated certificates.

Ensure you are covered by the independent Cavity Wall Guarantee Agency (CIGA)

A concern to many people is the cases were properties have experienced damp and condensation after the installation of cavity wall insulation. The main factors being, the inherent property issues not detected at the assessment stage and inadequate installation of the insulating material.

Our cavity wall assessments are monitored by the Cavity Assessment Surveillance Scheme, CASS®, which validates the process of checks to ensure that all property assessments meet BBA requirements. We only instruct BBA approved installers to fit the appropriate insulating material for your property to ensure you receive your independent guarantee six weeks after installation.

For advice or to book your assessment simply complete the form below or call 0330 311 0118