Cavity Wall Insulation & Installation Costs | Effective Home

Effective cavity
wall insulation

Save up to £480 off your energy bills every year.

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The benefits of cavity wall insulation

  • Reduced heat loss – saving on bills and carbon emissions
  • Warmer home in winter, cooler in summer
  • Less condensation on inner walls
  • Increased value of property (EPC)
  • Quick, simple installation from outside
  • Effective for lifetime of property

You could qualify for free home insulation under the ECO scheme

  • Free loft and cavity wall insulation
  • Reduce heating bills and energy waste
  • Easy to apply – we can help

Do I qualify?

Costs and savings

A third of all heat loss is through the walls of uninsulated homes.

By properly insulating cavity walls, you will save energy and reduce your heating bills. It’s great for your carbon footprint too.

You should be able to make back the cost of cavity wall insulation in around 5 years due to it costing less to heat your home and it’s guaranteed to work effectively for 25 years.

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  • Cost of cavity wall insulation
    from £680 for a 3-bed house
  • Insulating your walls could
    save £480 a year on your heating bills
  • Carbon footprint impact
    Save 1100kg CO2 a year Carbon dioxide savings

Insulate other parts of your home for even lower bills with Loft insulation

Not all walls have cavities…

Most houses built since the 1990s already have wall insulation, but if your house is older than that, it may not have any.

Your home could be suitable for standard cavity wall insulation if:

  • Its external walls are unfilled cavity walls.
  • Your cavity is at least 50mm wide, and is clear of rubble.
  • The masonry or brickwork of your property is in good condition.
  • The walls are not exposed to driving rain.
  • Your house is not at risk of flooding

One of our installers will carry out a survey to check that your house is suitable for cavity wall insulation before going ahead. This service is free of charge with no obligation.

Why choose Effective Home for cavity wall insulation?

  • Free, no-obligation home energy survey
  • Installation at your convenience plus easy ways to pay
  • Hassle-free – our experts will leave your home clean and tidy, with minimum disruption
  • Increase your home’s EPC energy rating
  • 25-year guarantee on cavity wall insulation
  • Over 30 years’ insulation experience
  • Approved installers and certified products


Is cavity wall insulation right for my home?

If your house was built in the last 20 years or so, the walls are probably already insulated. If you’re not sure whether a) your walls have cavities, or b) if you have cavity wall insulation already, we can help.

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.

How does cavity wall insulation get inside the wall?

Most cavity walls can be insulated by injecting insulation material into the cavity from the outside. Your installer will drill small 22mm drill holes at intervals in your outer walls, inject insulation through the holes using specialist equipment, and then seal them with cement. The insulation materials are usually either mineral wool or polystyrene beads, but polyurethane foam may sometimes be used instead.

Once all the insulation is in, we’ll fill the holes in the brickwork so you’ll barely notice them.

How long does it take to insulate cavity walls?

Filling cavity walls is not a job you can do yourself, you will need to employ a registered installer. Effective Home can do the job in around two hours for an average house with easily accessible walls. It shouldn’t make any mess.

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