Positive Input Ventilation & Air Quality Improvement in Dorset, Hampshire & Wiltshire
Poor indoor air quality and condensation are usually a ventilation problem. Proofterior installs Positive Input Ventilation (PIV) and related solutions that keep humidity down, prevent condensation and mould, and give your home a constant supply of fresh, filtered air.
- ISSE accredited
- 25-year insured guarantee
- In-house specialist team
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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 Positive Input Ventilation & Air Quality Improvement?
Positive Input Ventilation (PIV) is a whole-home ventilation system that gently introduces a continuous flow of fresh, filtered air, usually from a discreet unit in the loft. By slightly pressurising the home it dilutes and displaces the stale, moisture-laden air that causes condensation and mould, replacing it with drier, cleaner air. PIV is quiet, low-cost to run and highly effective in properties that suffer from stuffy air, streaming windows and recurring condensation.
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
- Streaming condensation on windows, especially in the morning
- Recurring black mould around windows, corners or ceilings
- Stuffy, stale air that never seems to clear
- Musty smells and a generally humid feel indoors
- Damp, cold rooms that are hard to keep comfortable
- Worsening allergy or respiratory symptoms indoors
Our treatment process
Every job follows the same careful, diagnosis-first method — so you know exactly what is happening and why at each stage.
Assessment of humidity, ventilation and air movement throughout the home
Specifying the correct PIV unit and any supporting ventilation
Installing the PIV unit, typically in the loft, with a discreet ceiling diffuser
Commissioning and setting the system for your property
Advice on getting the best performance and results
Positive Input Ventilation & Air Quality Improvement — 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.
Positive Input Ventilation & Air Quality Improvement across Bournemouth, Poole & the South Coast
Proofterior is a local, in-house team providing Positive Input Ventilation & Air Quality Improvement right across Dorset, Hampshire and Wiltshire. Homeowners in Bournemouth, Poole, Christchurch, Southampton, Salisbury and the surrounding towns rely on us for honest diagnosis and lasting results. Whether you are searching for Positive Input Ventilation & Air Quality Improvement in Bournemouth, need a specialist in Poole, or want trusted advice anywhere along the South Coast, our surveyors know the local property styles and the problems they typically face — and we are usually with you within days.
Covering Dorset, Hampshire & Wiltshire
Local knowledge, specialist expertise and lasting protection for the home you care about.
Everything you might be wondering
PIV continually introduces fresh, filtered air and displaces the humid, stale air that condensation and mould need. Keeping indoor humidity low removes the conditions mould relies on to grow.
No. PIV units are designed to be very economical, typically costing only a few pounds a year to run while making a substantial difference to air quality and condensation.
Related services
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.