Cavity Wall Insulation

To find out if you qualify, or to book a free no-obligation survey, complete our enquiry form or give us a call

📞 0800 8 10 10 60
📞 07960 799681

FAQs Cavity Wall Insulation in Wales

The simple answer is, “I can’t tell you without conducting a survey.” However…

If your home was built after 1925, there’s a good chance it has external walls consisting of two layers of brick with a gap (cavity) between them, held together by wall ties. This is referred to as a cavity wall.

Free cavity wall insulation in Bristol fills this gap, which helps retain warmth, saves energy, and may also reduce or eliminate condensation inside your home, particularly if your external walls are prone to moisture problems.

Your home will likely be suitable for free cavity wall insulation if:

•The external walls have unfilled cavity walls.
•The cavity is at least 50mm wide.
•The brickwork or masonry is in reasonably good condition.

However, it’s not quite as simple as that.

Part of the process includes a Cavity Assessment Survey (CAS), which is administered and audited by the Installation Assurance Authority (IAA). This thorough survey assesses the suitability of the walls for insulation.

During the survey, small test holes are drilled into each wall elevation, and a borescope (a special camera) is used to inspect the cavity, taking photographs and measuring the depth, etc.

The walls are carefully examined for issues such as cracks, unfilled holes, or other remedial work that must be addressed before insulation can proceed. Gutters and downpipes are also inspected to check for leaks, blockages, and proper drainage.

To find out if you qualify, or to book a free no-obligation survey, complete our enquiry form or give us a call

📞 0800 8 10 10 60
📞 07960 799681

FAQs Cavity Wall Insulation in Wales

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.

We drill small holes (about 22mm in size) in the outside walls of your home. The holes are about 1 metre apart. We always insulate from the bottom up.

The exact pattern of the holes is laid down in the British Board of Agrement (BBA) Certificate, which is issued for the material that is being used to insulate the walls.

We always use polystyrene beads.

We then blow the insulation into the cavity using special equipment.

Once all the insulation is in, we fill the holes in the brickwork with cement. It is then colour-matched to the render or mortar, so you’ll barely notice them.

Our Installers are among the best in the business. They have been insulating cavity walls for the past 45 years. You will 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.

Our work is also guaranteed for 25 years by CIGA – the Government-backed Cavity Insulation Guarantee Agency.

Cavity Wall Insulation Bristol can reduce the amount of heat escaping from your walls by 70%. It can also reduce CO₂ emissions by up to 3 tonnes per year.

To find out if you qualify, or to book a free no-obligation survey, complete our enquiry form or give us a call

📞 0800 8 10 10 60
📞 07960 799681

FAQs Cavity Wall Insulation

Yes, it comes with a 25-year guarantee issued by the Cavity Insulation Guarantee Agency (CIGA).

The Cavity Insulation Guarantee Agency provides independent 25-year guarantees for Free Cavity Wall Insulation in Bristol.

However, they will only issue a guarantee if the property has passed a CAS survey (cavity assessment survey).

A grant will not be allowed unless a CIGA guarantee is issued.

CIGA 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 CAS 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.

To find out if you qualify, or to book a free no-obligation survey, complete our enquiry form or give us a call

📞 0800 8 10 10 60
📞 07960 799681

FAQs Cavity Wall Insulation in Wales

Yes. The scheme is part of the Great British Insulation Scheme, funded by energy companies through the Energy Company Obligation (ECO).

A portion of all UK energy bills includes a “green levy,” which helps fund measures such as free cavity wall insulation.

To find out if you qualify, or to book a free no-obligation survey, complete our enquiry form or give us a call

📞 0800 8 10 10 60
📞 07960 799681

FAQs Cavity Wall Insulation in Wales

We use SuperBead polystyrene beads, not mineral fibre.

Why SuperBead?

• Excellent thermal performance (0.035 conductivity)
• Highly water-resistant
• Reduces condensation
• Safe and fire-resistant
• Long-lasting and rot-proof
• Up to 20% more efficient than fibre insulation
• 30% fewer holes in the walls

SuperBead is blown into the cavity with adhesive that sets in about 20 minutes, creating a solid, efficient thermal layer.

To find out if you qualify, or to book a free no-obligation survey, complete our enquiry form or give us a call

📞 0800 8 10 10 60
📞 07960 799681

FAQs Cavity Wall Insulation in Wales

Yes — many households in Wales can qualify for free cavity wall insulation under the Great British Insulation Scheme (GBIS).

There are two ways to qualify:

1. The General Group

You can qualify through this route if your property meets the following requirements:

Council Tax Band

• Wales: Band A to E
• England: Band A, B, C or D

(You can check your band on the  Gov.UK  website.)

EPC Rating

Your property must have an EPC rating of D, E, F, or G. This can be verified on the EPC Register.
You do not need an EPC beforehand — we create an EPR (Energy Performance Report) as part of the process.

Who can apply?

• Homeowners
• Private renters (with landlord permission)

Extra rules for private tenants

• You must receive a qualifying benefit.
• The property must be EPC D or E.
• EPC F or G rental homes must have a registered exemption to qualify.

2. The Low-Income Group

You qualify under this group if your property has an EPC rating of D, E, F, or G, and you receive at least one of the following:

• Pension Credit
• Income-Based Jobseeker’s Allowance
• Universal Credit (no income limit)
• Income-Related Employment & Support Allowance
• Working Tax Credit or Child Tax Credit (no income limit)
• Income Support
• Housing Benefit
• Child Benefit (income limits apply)

Child Benefit Income Thresholds

Children	1 Adult	2 Adults
1	£19,900	£27,500
2	£24,800	£32,300
3	£29,600	£37,200
4	£34,500	£42,000

To find out if you qualify, or to book a free no-obligation survey, complete our enquiry form or give us a call

📞 0800 8 10 10 60
📞 07960 799681

FAQs Cavity Wall Insulation in Wales

Yes, but renters must have landlord consent and be receiving at least one qualifying benefit, such as:

• Pension Credit
• Income-Based Jobseeker’s Allowance
• Universal Credit (no income limit)
• Income-Related Employment & Support Allowance
• Working Tax Credit or Child Tax Credit (no income limit)
• Income Support
• Housing Benefit
• Child Benefit (income limits apply)

Child Benefit Income Thresholds

Children	1 Adult	2 Adults
1	£19,900	£27,500
2	£24,800	£32,300
3	£29,600	£37,200
4	£34,500	£42,000

To find out if you qualify, or to book a free no-obligation survey, complete our enquiry form or give us a call

📞 0800 8 10 10 60
📞 07960 799681

FAQs Cavity Wall Insulation in Wales

An Energy Performance Certificate (EPC) shows how energy efficient a property is, rated A to G.

To qualify for a grant, your EPC must be a D, E, F or G.

If you don’t have an EPC, don’t worry — we produce an EPR, which is an unregistered EPC used solely for the grant assessment.

To find out if you qualify, or to book a free no-obligation survey, complete our enquiry form or give us a call

📞 0800 8 10 10 60
📞 07960 799681

FAQs Cavity Wall Insulation in Wales

You can still apply. We will generate an EPR (an unregistered EPC) during the survey at no cost.

To find out if you qualify, or to book a free no-obligation survey, complete our enquiry form or give us a call

📞 0800 8 10 10 60
📞 07960 799681

FAQs Cavity Wall Insulation in Wales

If you have damp on the inside of external walls, this must be fixed before insulation can be installed.

Properties with damp fail the CAS (Cavity Assessment Survey) and cannot be insulated under GBIS because a 25-year guarantee is required.

Black mould vs damp

Black mould is usually caused by condensation, not structural damp.
In about 90% of cases, it’s linked to lifestyle factors such as poor ventilation or drying clothes indoors.

Cavity wall insulation keeps internal walls warmer, which often reduces or eliminates condensation and mould.

To find out if you qualify, or to book a free no-obligation survey, complete our enquiry form or give us a call

📞 0800 8 10 10 60
📞 07960 799681

FAQs Cavity Wall Insulation in Wales

The only way to be 100% sure is through a full Cavity Assessment Survey (CAS).

However, your home is likely suitable if:

• The walls have an unfilled cavity
• The cavity is at least 50mm wide
• The brickwork is in reasonable condition
• The property was built after roughly 1925
• There are no signs of damp

Cavity Assessment Survey (CAS)

This survey, overseen by the Installation Assurance Authority (IAA) and carried out by Retrofit Assessors, includes:

• Drilling small test holes
• Inspecting the cavity with a borescope
• Checking for cracks, defects, rubble, or damp risks
• Examining gutters, downpipes, and drainage

The survey takes around two hours and is completely free.

To find out if you qualify, or to book a free no-obligation survey, complete our enquiry form or give us a call

📞 0800 8 10 10 60
📞 07960 799681

FAQs Cavity Wall Insulation in Wales

Yes — significantly.

Approximate heat loss in a typical home:

• Walls: 35%
• Roof: 25%
• Floor: 15%
• Draughts: 15%
• Windows: 10%

Insulation reduces heat loss through the wall by 70%.

For a 3-bed semi-detached house with mains gas, this can save around £450 a year, with even higher savings for oil, LPG or electric heating. It also reduces condensation and cuts carbon emissions.

To find out if you qualify, or to book a free no-obligation survey, complete our enquiry form or give us a call

📞 0800 8 10 10 60
📞 07960 799681

FAQs Cavity Wall Insulation in Wales

Modern cavity wall insulation is very unlikely to cause damp. Historically, issues occurred when:

• The wrong material (e.g., Rockwool) was used
• Homes were insulated without proper surveys
• Early polystyrene beads lacked water resistance

Today, materials and quality standards are far superior.

Quality control improvements

Since 2017, the British Board of Agrément (BBA) and later CIGA have enforced strict pre-installation checks under the Cavity Assessment Surveillance Scheme (CASS).

Every property receives:

• A full cavity inspection
• Photo evidence
• Structural and moisture checks
• Desktop audit by CIGA
• 1 in 10 homes also has an on-site CIGA re-inspection

This dramatically reduces the risk of damp being caused by insulation.

To find out if you qualify, or to book a free no-obligation survey, complete our enquiry form or give us a call

📞 0800 8 10 10 60
📞 07960 799681

FAQs Cavity Wall Insulation in Wales

No. A survey is essential. Unsuitable homes include:

Homes built after 1982 (many insulated when built, though not always)

Solid wall properties (common pre-1920, no cavities)

Concrete properties can suffer structural problems such as “Concrete Cancer”. Usually built by Local Authorities.

Timber-framed houses the external walls have a single brick skin, and on the inside of the house, a timber frame. The timber frame would have been insulated

To find out if you qualify, or to book a free no-obligation survey, complete our enquiry form or give us a call

📞 0800 8 10 10 60
📞 07960 799681

FAQs Cavity Wall Insulation in Wales

• Lower heating bills
• Warmer, more comfortable rooms
• Reduced condensation and mould
• Lower carbon emissions
• Increased property value
• Less outside noise entering the home
• Quick, low-disruption installation

To find out if you qualify, or to book a free no-obligation survey, complete our enquiry form or give us a call

📞 0800 8 10 10 60
📞 07960 799681

FAQs Cavity Wall Insulation in Wales

Yes.
Condensation forms when warm, moist air meets cold surfaces. By warming internal walls, cavity wall insulation reduces the risk of condensation and black mould.

To find out if you qualify, or to book a free no-obligation survey, complete our enquiry form or give us a call

📞 0800 8 10 10 60
📞 07960 799681

FAQs Cavity Wall Insulation in Wales

If you have your cavity wall insulated, we will reward you with £50.

You would receive it within 21 days of the installation.

To find out if you qualify, or to book a free no-obligation survey, complete our enquiry form or give us a call

📞 0800 8 10 10 60
📞 07960 799681

FAQs Cavity Wall Insulation in Wales