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  Cardiff Buildings

Making your Home cheaper to run.

Telephone: 0800 8 10 10 60





Free Cavity Wall Insulation Grants in Cardiff, Bridgend, Caerphilly and throughout South Wales.

All homeowners and private tenants qualify for a grant regardless of financial circumstances (subject to survey).



Tap and call 07960 799 681 (from Smartphones)


Is Cavity Wall Insulation really Free in Cardiff?

In more than 80% of the cases, yes, Cavity Wall Insulation is Free. For the remaining 20% of the cases where it is not free, it is still significantly subsidised - it is very rare to have to make a contribution of more than £100.

At the moment everyone qualifies for the Standard Grant for Cavity Wall Insulation, and if you live in a 3 bed semi-detached house, the maximum that you would have to pay today towards the cost would be £100. 

From September you will have to pay the full cost - and that's £600 - £900 depending on the size of the property, unless you qualify for the new "Enhanced Grant".

We always install Polystyrene Beads and not "RockWool" (fibre). Polystyrene Bead is a superior material for insulating Cavity Walls, but it is more expensive.

Polystyrene Bead is up to 20% more efficient than fibre insulation. It is blown into the cavity of the walls with an adhesive which "goes off" in about 20 minutes, leaving a "solid" blanket of polystyrene wrapped around your home, reducing the heat loss through the walls by about 70%.

An average 3 bedroomed semi-detached house will take about 3 hours to insulate. There are about 30% fewer holes than using fibre, and the holes are smaller.

The beads have been thoroughly tested and will not deteriorate over time. They are fully fire resistant and have full BBA (the British Board of Agrément) approval for use in even the most extreme of conditions.

As a part of the initial survey we also carry out a CASS (Cavity Assessment Surveillance Scheme) survey, to assess the suitability of your walls to be insulated. This is a part of the improved quality control measures that have been put in place under this new grant scheme.

The average "cash price" for installing cavity wall insulation in Cardiff with polystyrene beads into a 3 bedroomed semi detached house is £800, so a customer contribution of £100 means the Government Insulation Grant is still covering 87.5% of the cost - and these government insulation grants are available to everyone, they are not "means tested" (even Richard Branson would qualify for one) and they are not repayable.



How is Cavity Wall Insulation Funded?

The Government have (for at least another couple of years) massive European targets to reduce Carbon Emissions. The Government, as Governments do, passed the buck. They gave a Legal Obligation to the Gas and Electricity companies to reduce Carbon Emissions. This is know as the Energy Company's Obligation, ECO for short.

From April 2017, the system has been simplified and an energy assessment is no longer required. Instead the Government have "deemed" an amount of Carbon Emission savings for each type of property - terraced, semi-detached, detached, 2 bed, 3 bed, 4 bed etc. We then sell these Carbon Emission savings to one of the Gas and Electricity companies - and that is how it is funded. We all pay an amount on our fuel bills towards this fund, so yes, we pay for it, as usual.


Are my Cavity Walls suitable for insulating?

If your home was built after 1925, the chances are that its external walls are made of two skins of brick with a gap or cavity between them, held together with wall ties. Cavity Wall Insulation fills that gap, keeping the warmth in - thus saving energy. It can also help reduce condensation inside the house if this is a problem on your external walls.

Your home will usually be suitable for cavity wall insulation if:

  • the external walls are unfilled cavity walls
  • your cavity is at least 50mm wide
  • the masonry or brickwork of your property is in reasonably good condition
  • properties built after 1982 now qualify for a grant

What if there is damp? 

If you have any damp patches on your external walls then they should not be insulated until the cause of the damp has been resolved. In fact, if there is damp, the property will fail the CASS survey, and we will not install cavity wall insulation. To get a Grant there must be a 25 year guarantee issued. To get a 25 year guarantee issued the property must pass a CASS survey. So if there is damp there is no Grant - simples.

If it is "Black Mould / Spots" then this is probably Condensation and not Damp. 90% of the time Condensation is a lifestyle issue rather than a structural issue. However, Cavity Wall Insulation can help reduce/eradicate Condensation.

How is Cavity Wall insulation installed? 

Filling cavity walls is not a job you can do yourself. We do the job in around 2-3 hours for an average house with easily accessible walls. It is simple, quick - and with no mess. 

Cavity Wall Insulation can reduce the amount of heat escaping from your home by up to 35% (70% of the heat lost through the walls) and can reduce CO2 emissions by up to 3 tonnes per year. 

  • Most homes built of brick between 1925 and 2017
  • Blown into the gap between two skins of brick.
  • Installed from the ground floor to the roof. 

Free Cavity Wall Insulation being installed

Our Installers are among the best in the business, and they will make good the holes with closely-matching filler, so that you have a first-class result with the minimum of fuss and disruption. Most of our customers are amazed at how quickly and neatly this operation can be carried out and our work is guaranteed for 25 years by CIGA – the Government-backed Cavity Insulation Guarantee Agency – offering you complete peace of mind.

Peace of Mind

The Cavity Insulation Guarantee Agency provides independent 25 year guarantees for Cavity Wall Insulation fitted by registered installers in the UK and Channel Islands. 

The Government regards cavity wall insulation as "the most effective energy savings measure that most people can carry out on their homes" and a major contributor to reducing carbon emissions.   

The Cavity Insulation Guarantee Agency was established in consultation with the Government's Energy, Environment and Waste Directorate (a division of DETR) to provide householders with an independent, uniform and dependable guarantee covering defects in materials and workmanship.

Independent research carried out for the Department of the Environment, Transport and the Regions (DETR) has confirmed that cavity wall insulation is a very reliable process.

Problems are therefore extremely rare, but if they do occur, CIGA has the expertise to ensure that they are swiftly rectified. The new CASS survey will also reduce the potential for future problems, by only insulating walls that are suitable.

CIGA also operates and administers the Cavity Wall Insulation Self Certification scheme (CWISC) in association with the British Board of Agrément. The scheme provides homeowners with the comfort of knowing that work by registered contractors complies with the requirements of the Building regulations.

Book a Survey

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To call from a Smartphone just tap this number      0800 8 10 10 60       or this one    07960 799681

otherwise call us on one of the numbers below

Freephone: 0800 8 10 10 60  Mobile: 07960 79 96 81 Landline: 01443 815583

or you can complete the online enquiry form below.

Click here to complete a short Online Enquiry Form



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