Cavity Wall Insulation Removal & Extraction
When cavity wall insulation gets wet, slumps or was never suitable for your walls, the only lasting fix is to take it out. Proofterior carry out full cavity wall insulation removal across Dorset, Hampshire and Wiltshire — extracting failed mineral wool, loose fibre and beads, proving the cavity is clear on camera, and making good so the wall looks as it did before. Backed by our 25-year insured guarantee.
- ISSE accredited
- 25-year insured guarantee
- In-house specialist team
Book your complimentary survey
Tell us what is happening and a specialist will find the real cause and give you a fixed price to fix it. No obligation.
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Genuine reviews from local homeowners
Over 200 verified reviews across Checkatrade, Google and Yell
“Excellent service from start to finish. The survey was thorough and professional, with honest, evidence-based advice rather than trying to sell unnecessary work. I came away with complete peace of mind.”
Alex Richards-Taylor
Google review
“Excellent service throughout. Ashton came out to look at an issue raised on a part-exchange survey and, rather than recommend expensive remediation, told me honestly there was nothing wrong with the wall. Great to have an honest discussion.”
Ian M.
BH16 · Damp Investigation
“Dylan and the Proofterior team were amazing. The report was incredibly comprehensive. Can’t recommend them enough.”
Sam Short
Google review
“Very pleased with the work on our living room and bedroom walls. Punctual, polite and friendly, and completed on time even though it was Easter week. Many thanks to everyone at Proofterior.”
Chris G.
BH20 · Penetrating Damp Treatment
“Dan was very thorough, professional and polite. Quick to respond and I would highly recommend.”
Malik R.
Yell · Quick & Professional
“The workmen were clean, pleasant and efficient and took just one day. The very next day we noticed a big difference with the damp issue. Many thanks.”
Nick Bennett
Google review
“Able to fit my job in for the next day and completed in a day as agreed. Not the lowest quote, but it comes with a 25-year guarantee, which I wanted — long-term peace of mind was vital.”
Alan M.
BH23 · Flat Roof Reseal
“Ashton was so friendly and informative. I’ve gone from worried to empowered — someone you can trust to do the right thing.”
Suzanna Furbank
Google review
“Really amazing service. Dan provided a really thorough damp investigation and a very helpful damp report. Very quick responses too.”
Paul A.
Yell · Damp Investigation
“Happy with the speed — a full flat survey within a week. They explained our options, the price was extremely competitive, and our tenants are pleased with their fresher, safer flat.”
Verified Customer
SP6 · Damp Proofer
“Dan provided a very professional service from start to finish. Very good communication and a first-class job.”
Mark H.
Yell · Professional Service
“Excellent service from start to finish. The survey was thorough and professional, with honest, evidence-based advice rather than trying to sell unnecessary work. I came away with complete peace of mind.”
Alex Richards-Taylor
Google review
“Excellent service throughout. Ashton came out to look at an issue raised on a part-exchange survey and, rather than recommend expensive remediation, told me honestly there was nothing wrong with the wall. Great to have an honest discussion.”
Ian M.
BH16 · Damp Investigation
“Dylan and the Proofterior team were amazing. The report was incredibly comprehensive. Can’t recommend them enough.”
Sam Short
Google review
“Very pleased with the work on our living room and bedroom walls. Punctual, polite and friendly, and completed on time even though it was Easter week. Many thanks to everyone at Proofterior.”
Chris G.
BH20 · Penetrating Damp Treatment
“Dan was very thorough, professional and polite. Quick to respond and I would highly recommend.”
Malik R.
Yell · Quick & Professional
“The workmen were clean, pleasant and efficient and took just one day. The very next day we noticed a big difference with the damp issue. Many thanks.”
Nick Bennett
Google review
“Able to fit my job in for the next day and completed in a day as agreed. Not the lowest quote, but it comes with a 25-year guarantee, which I wanted — long-term peace of mind was vital.”
Alan M.
BH23 · Flat Roof Reseal
“Ashton was so friendly and informative. I’ve gone from worried to empowered — someone you can trust to do the right thing.”
Suzanna Furbank
Google review
“Really amazing service. Dan provided a really thorough damp investigation and a very helpful damp report. Very quick responses too.”
Paul A.
Yell · Damp Investigation
“Happy with the speed — a full flat survey within a week. They explained our options, the price was extremely competitive, and our tenants are pleased with their fresher, safer flat.”
Verified Customer
SP6 · Damp Proofer
“Dan provided a very professional service from start to finish. Very good communication and a first-class job.”
Mark H.
Yell · Professional Service
What is Cavity Wall Insulation Removal & Extraction?
Cavity wall insulation removal (also called cavity wall insulation extraction) is the process of taking failed insulation out of the gap between the two leaves of a wall. Small holes are drilled at the mortar joints, the fill is broken up with compressed air and drawn out with an industrial vacuum into sealed bags. A borescope camera then checks the cavity is clean, including the bottom where debris collects, before the holes are filled with mortar matched to your existing joints. Extraction is recommended when the insulation is wet and carrying damp across the cavity, has slumped to leave cold spots, has been contaminated with debris, or was installed in a wall that should never have been filled. Removal alone is not always the end of the job: we also fix the external defect that let water in, so the wall can dry out and — where suitable — be re-insulated.
The warning signs to look for
Catching the problem early keeps repairs simpler and less costly. If you notice any of these signs, it is worth booking a specialist survey before the damage spreads.
Book a complimentary survey
- A borescope survey has shown wet, slumped or patchy insulation
- Damp patches on outside walls since the cavity was filled
- Black mould returning on external walls however often it is cleaned
- Cold spots and condensation on inside walls
- Insulation installed in an exposed, weather-facing elevation
- Cavity narrower than 50mm, or filled with rubble or debris
- A mortgage lender or surveyor has flagged the cavity insulation
- Wall tie replacement or structural repairs need a clear cavity
Our treatment process
Every job follows the same careful, diagnosis-first method — so you know exactly what is happening and why at each stage.
Survey: borescope inspection and moisture readings confirm the type and condition of the fill and that removal is the right answer.
Preparation: we protect the garden, paths and windows, and set up the extraction unit and sealed collection bags.
Drilling: holes are drilled at the mortar joints in a grid across each elevation, avoiding damage to the bricks.
Extraction: compressed air breaks up the insulation and an industrial vacuum draws it out, working down the wall so nothing is left at the base.
Camera check: we inspect the cavity with a borescope, clear any remaining debris at the bottom and show you the results.
Making good: holes are filled with colour-matched mortar, waste is removed under our waste carrier registration, and we advise on re-insulation.
Is extraction the right answer?
Not every damp wall with cavity insulation needs the insulation taken out. Sometimes the fill is dry and doing its job, and the damp is coming from a leaking gutter, a bridged damp proof course or condensation. Taking out good insulation would cost you money and make the house colder.
That is why every removal starts with a borescope survey. We only recommend extraction where the evidence shows the insulation is wet, slumped, contaminated or installed in an unsuitable wall — and we tell you plainly when it is not needed.
- Wet or saturated fill carrying damp to the inner wall
- Slumped fibre leaving voids and cold spots
- Debris or mortar bridging at the base of the cavity
- Fill in very exposed walls, narrow cavities or non-traditional construction
Fixing the cause, then re-insulating
Removing the insulation stops it carrying water across the cavity, but the wall still needs to stay dry. We repair failed pointing, cracked render, leaking gutters and downpipes, and can apply a breathable masonry water-repellent cream to exposed elevations.
Once the cavity is clean and the walls have dried, we can re-insulate with bonded polystyrene beads where the wall is suitable — a material that does not wick water across the cavity the way loose fibre can.
Cavity Wall Insulation Removal & Extraction — from our recent projects
Real photos from Proofterior jobs across Dorset, Hampshire and Wiltshire — carried out by our own in-house team.
Included as standard
Built to impress, built to last
Diagnosis first
We identify the real cause before recommending any treatment. No guesswork, and never unnecessary work.
In-house specialist team
Vetted, Proofterior-trained specialists, managed by us from survey to completion. No compromises.
25-year guarantee
Every treatment is backed by our 25-year insured guarantee, giving you lasting protection and peace of mind.
Cavity Wall Insulation Removal & Extraction across Bournemouth, Poole & the South Coast
Cavity wall insulation removal is in high demand along the South Coast. Homes facing the sea in Southbourne, Boscombe, Sandbanks, Highcliffe, Milford on Sea and Southsea take the full force of wind-driven rain, which is exactly where mineral wool fill tends to fail. Inland, 1930s and post-war semis in Kinson, Oakdale, Shirley, Bitterne, Andover and Salisbury often had insulation pumped in under past grant schemes without a proper survey. Our team works across Bournemouth, Poole, Christchurch, Southampton, Portsmouth, Winchester, Salisbury and the towns and villages in between.
Covering Dorset, Hampshire & Wiltshire
Local knowledge, specialist expertise and lasting protection for the home you care about.
Everything you might be wondering
Most houses take one to three days, depending on the size of the property, the type of insulation and access. Larger or detached homes, or walls needing scaffolding, can take longer. Your written quote includes a timescale.
Very little mess reaches your home. Extraction is done from the outside and the insulation goes straight into sealed bags. We protect paths, plants and windows and leave the site clean.
Mineral wool, loose fibre and loose bead systems can usually be extracted. Bonded beads take longer, and sprayed or injected foam often cannot be vacuumed out and may need sections of brickwork removing. The survey tells you what you have before any work is quoted.
Typical UK figures for a standard house range from around £900 to £2,000, rising for large or complex properties and foam insulation. The price depends on wall area, insulation type, access and whether scaffolding is needed. We give a fixed written quote after the survey.
An empty cavity loses more heat than a properly insulated one. Once the external defects are fixed and the wall is dry, we can re-insulate with bonded beads where the wall is suitable, so you get the warmth back without the damp.
Not always. Sometimes only one exposed elevation is affected. We survey each wall and only recommend removal where the insulation is actually failing.
We can, but speak to your installer and CIGA first. Removing insulation privately while a claim is open can affect the guarantee. We can provide an independent survey report to support your claim.
Get clear, honest answers about your home
A qualified specialist will visit your property, carry out a thorough inspection and give you clear recommendations in plain English — everything explained in one visit, with no obligation.