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Wall Insulation

If your home is uninsulated, approximately a third of the heat is lost through your walls. To be able to maximise your energy efficiency upgrades with Wall Insulation, its important to understand the brickwork of your homes and there two main types – solid walls & cavity walls

Solid Walls

Your home is likely to consist of solid walls if it was built pre-1920. Solid walls have no cavity with each wall being a single solid wall that are usually made out of brick or stone. Solid walls are normally constructed to be more narrow than cavity walls (i.e. less than 260mm thick). When looking at the brickwork pattern outside of your house, solid wall bricks will have an alternating pattern that are laid, i.e. some bricks are lengthways and across the wall.

Cavity Walls

If your house was built after the 1920s, it is likely to have cavity walls. Cavity walls are made up of two walls with a gap between which is known as the ‘cavity’. Outer wall (layer) will usually be made of brick with the inner layer brick or concrete. Your home will have cavity walls if the bricks are usually laid lengthways consisting of an even pattern. If the brick wall has a greater thickness of 260mm then its likely to have a cavity.

TYPES OF WALL INSULATION

Once you have identified your home’s brickwork type you can choose the insulation type suitable for you! Wall insulation offers three different types and these different types will have specific installation requirements, cost variations based on your house type and offer benefits that could be personalised to you such as saving on your energy bills and reducing your carbon footprint!

A common barrier to becoming energy efficient can be costs needed to make these steps, so to support this there are a wide range of loans / grants residents can apply for to give you an opportunity to take these next steps to making your home more sustainable, supporting our net zero journey!

INTERNAL WALL INSULATION (SOLID WALLS)

  • Insulation done by fitting rigid boards to the wall, or by building a stud wall filled with insulation materials.
  • Thickness of the insulation tends to be around 100m.
  • Will slightly reduce your rooms floor area.
  • Installation costs for Internal Wall Insulation are typically around £7,500 (estimates for a typical 3 bedroom semi-detached house).

EXTERNAL WALL INSULATION (SOLID WALLS)

  • Insulation involving fixing a layer of insulation material to the wall, which is then covered over with a special type of plasterwork or cladding.
  • Applications won’t disrupt the floor size area.
  • Can additionally improve weatherproofing and the sound resistance of your home.
  • Installation costs for External Wall Insulation are around £11,000 (estimates for a typical 3 bedroom semi-detached house).

CAVITY WALL INSULATION (CAVITY WALLS)

  • Insulation material that will be injected into the ‘cavity’ section of the wall from the outside.
  • Material injected is usually made of either mineral wood or polystyrene beads however polyurethane foam may sometimes be used instead.
  • Cavity wall insulation costs can be around £2,700 (this is an estimated price for a semi-detached house).

BENEFITS OF WALL INSULATION

  • Wall insulation will have two significant benefits alongside keeping your heat in your homes!
  • Its been shown that all house types can have energy bill savings each year from its insulation. Solid wall savings can range from
  • £150-550 per year and cavity walls savings ranging from £110-410 per year.
  • Additionally, insulation across all housing types have shown to have carbon savings. Solid wall carbon savings range from 410-1,500kgCO2/year with cavity wall carbon savings ranging from 310-1,100kgCO2/year.
  • For further information about energy bill and carbon savings, visit the Energy Saving Trust website.