Cost of Cavity Wall Insulation
Insulation prices for cavity walls
It was standard practice for some time that homes were built with double walls, using a cavity between them to prevent rain penetrating from the outside and to provide some insulation. However, it has long been known that unfilled wall cavities will let heat escape from the inside, therefore, placing increased demand on your heating system, which means higher energy bills. Organisations such as The Energy Saving Trust estimate around 35% of heat loss from homes can be through cavity walls which are not insulated. Installing cavity wall insulation is a reliable way and fairly cheap way to make your home warmer and save you money on heating bills. Cavity wall insulation simply means filling the cavity with an insulating material, usually some sort of foam which is pumped through holes which are drilled in the external wall.
Average cavity wall insulation prices
Things to consider about cavity wall insulation
Not all homes are suitable for cavity wall insulation, you need to have a survey conducted first before you know if having cavity wall insulation installed is appropriate or not. Walls which are exposed to the heavy wind-driven rain, may not be suitable for insulation and best left as a cavity to avoid damp problems, especially if insulated using mineral wool or similar. The costs for cavity wall insulation depend on the size of your house and the insulating material used, but there may be grants available which may cover the cost of the insulation or at least part of it. The recognised trade bodies for the cavity wall insulation industry are the National Insulation Association, the Cavity Insulation Guarantee Agency and the British Board of Agrément. Free cavity wall insulation, or grants towards it, are available from some energy suppliers under the Energy Company Obligation (ECO) scheme.
The ECO scheme means large gas and electricity suppliers such as British Gas, EDF Energy, and Scottish Power – are obliged to help households with energy efficiency measures to save money on their energy bills and reduce carbon emissions. The Energy Company Obligation aims to cut carbon emissions and reduce fuel poverty across the UK with over £1.3billion spent on energy efficiency and heating measures each year. Installation of cavity wall insulation is usually done by a local contractor and it can be complicated to work out if you’re eligible for ECO funding or not, it really all depends on your home and if you receive any benefits. But even if you are not on benefits, you may still be eligible for help with insulation if you’re a social housing tenant in a home with a low energy efficiency rating.
Until quite recently, pretty much everyone was entitled to a grant for cavity wall insulation. However in 2016, a few things changed, specifically, the rates the cavity wall installers are paid per tonne of carbon saved have dropped. It is now for a house to get 100% funding for cavity wall insulation, most will have to make some contribution which will be entirely dependent on the energy performance certificate (EPC) of the property which will be carried out by a qualified energy assessor, normally paid for by the cavity wall installer.
Doing it Yourself
Cavity wall insulation is the process of injecting an insulating material into the gap between the walls. There are a variety of different types of insulating materials you can choose from, but they all work in the same way. If you have the right equipment, injecting cavity wall insulation is pretty straightforward. Small holes which are drilled between the bricks on the outer wall, then the insulating material is injected through the wall until it fills the cavity. Then the holes are filled in to match the brickwork as closely as possible. But before you decide to insulate the cavity, you should have the walls checked for damp and ensure that the damp proof course is intact all around the house. In addition, the brickwork all has to in good condition, if not, the wall will need to be repointed prior to any cavity insulation.
All essential ventilation openings including flues and air bricks in the cavity wall must also be checked and the installation should not proceed until these ventilation openings have been sleeved or otherwise modified to prevent then getting blocked up by the insulating material. The materials used to fill the cavity should be either Mineral Wool, Urea Formaldehyde Foam, or Expanded Polystyrene Beads. But remember, that if your cavity wall insulation is carried out as DIY job, it is unlikely you will be able to claim any grants toward the costs, so you need to do your sums very carefully to ensure the job would not be even cheaper if you hired a professional installer to do it for you with a grant! Las
Cavity wall checklist
- If your home was built between 1920 and 1990, it’s likely to have cavity walls with no insulation
- Walls regularly exposed to wind-driven rain are not suitable for cavity-wall insulation
- You need a registered installer to fit cavity wall insulation
- Cavity wall insulation is one of the most cost energy efficiency effective measures
Hiring a Tradesman Checklist
- Always get at least 2 quotes before hiring.
- Never pay the full amount upfront.
- Get the quote in writing.
- For any payment you make, always get a receipt.
- On more expensive jobs, ask for references.
- Check if the tradesman is a member of any trades associations.
- Make sure the tradesman has public liability insurance.
How much can I save per year with cavity wall insulation?
Are there any potential problems with cavity wall insulation?
Do I need wall insulation?
Do I need planning permission for cavity wall insulation?
Can I get financial help with the installation?
Price per m2 to supply and fit 300mm loft insulation to two houses with good access.
Submitted by Mark
Top up of loft insulation as bad condensation and mould appearing in my 2 bed maisonette. The existing loft insulation in the roof is peeling away also. Thank you.
Submitted by Joanne
I want to vault the ceiling (removing part of loft above, leaving timber quite like it is now) in the 1st floor bedroom (about 18 m2) in a chalet bungalow, insulate it, plasterboard it, paint all exposed timbers in black and add a wall separating the ceiling from the rest of the loft. I'd also like ...
Submitted by Monika
An area of boards to stand on has been previously insulated also a ladder would like a quote.
Submitted by Margaret
I have a 1920’s property in Boston Manor that already has a 1970’s loft conversion. I would like a velux style window fitting in the loft, and the current loft ceiling taken down and replaced with a fully insulated one as there is literally zero insulation.