.webp)
Jun 19, 2025
In the past, retrofitting properties focused heavily on insulation, with double glazing, cavity walls, and blanket insulation taking priority. But as we’ve wrapped our homes tighter, we’ve unintentionally boxed in stale air, allergens, and excess moisture. The result? Damp corners, mould spots, and a rise in health complications from poor indoor air quality.Mechanical Ventilation with Heat Recovery (MVHR) offers a sustainable solution that’s not just for new developments. More and more homeowners, landlords, and building maintenance teams are realising the benefits of an MVHR retrofit in their existing properties. And with UK Building Regulations tightening and net-zero goals on the horizon, there’s never been a better time to rethink how existing properties breathe.
What’s an MVHR system—and why should you care?
MVHR systems are whole-house ventilation systems that work quietly behind the scenes, extracting stale air from wet rooms (like kitchens and bathrooms) while supplying fresh, filtered air to living spaces. But what makes them beneficial is that they recover heat from the outgoing air to pre-warm the incoming air without the two airflows ever mixing.
An MVHR system creates continuous, balanced ventilation with up to 90% heat recovery efficiency. This improves EPC scores, reduces reliance on gas boilers or electric heaters, and enhances occupancy comfort and air quality, year-round.
Why consider an MVHR retrofit?
If your property development or home is already built and bustling, you might be wondering, “Is it too late for MVHR?” The answer is no, not at all. Here are four reasons why you should seriously consider an MVHR retrofit.
Beat the mould, banish the damp
Older homes can become stuffy and moisture-prone, especially those upgraded with double glazing and insulation. MVHR systems solve this by maintaining consistent humidity and airflow and removing moisture before it becomes a problem—no more condensation streaks or musty odours.
Futureproof your energy bills
MVHR isn’t just about airflow—it’s a savvy heat recycler that recaptures already-generated heat. Reclaiming warmth that would otherwise escape can lead to a 20-30% energy cost saving, particularly in colder months, making MVHR a smart move amidst rising energy costs. It’s also worth noting that though the upfront costs can be hefty, retrofitting MVHR does increase property value, especially for eco-conscious buyers or those seeking Passivhaus-level performance.
Cleaner, healthier indoor air
From pollen to PM2.5 particles and VOCs from paints and plastics, indoor air is often more polluted than outdoor air and can wreak havoc on occupant health. MVHR systems use high-grade filters to remove these invisible health risks, making homes safer, especially for asthma sufferers, children, and the elderly.
A step toward net-zero
UK Building Regulations, like Approved Document F, favour energy-efficient ventilation systems like MVHR as they support national carbon reduction goals. This means retrofitting is a future-ready move for forward-thinking homeowners and property managers alike.
Creating better living spaces
Besides the financial and energy advantages, MVHR systems transform homes and how they feel for those living there. They provide consistent, comfortable temperatures evenly distributed throughout the house while being whisper-quiet (unlike noise extractor fans or open windows), leading to better sleep quality—an unsung benefit for family health.
Their effective air filtration also makes odour control easy. Cooking odours, pet smells, and musty corners are continuously ventilated for optimal smell, which also minimises allergens and pollutants while keeping homes comfortable for all the senses.
Similarly, by controlling humidity through efficient airflow, MVHR systems protect against rot, mould, and mechanical wear and tear, ultimately reducing ongoing paintwork, appliance, and insulation maintenance costs.
Overall, pursuing an MVHR retrofit will yield considerable benefits, which your wallet and health (as well as those of your family and tenants) will thank you for.
Important MVHR retrofit steps
Retrofitting MVHR is a craft, not a quick fix. However, with strategic planning, optimal design, and expert support, it can be implemented smoothly and with minimal disruption.
1. Start with a ventilation survey
First, begin your MVHR retrofit process with a professional ventilation survey. This helps to identify airflow patterns, leakage points, airtightness, layout, insulation levels, and current ventilation methods. These insights will help determine whether the property is airtight enough for an MVHR system to function optimally.
2. Design around building constraints
MVHR retrofits require bespoke ducting, and newer property builds are generally more suited to retrofits due to their better air permeability. Solutions like bulkhead or ceiling void installations, boxing-in ductwork in cupboards or built-in wardrobes, running ducts through loft spaces or floors, or using decentralised MVHR systems in apartments or flats, can help achieve optimal ventilation and heating performance more effectively.
3. Professional installation and commissioning
An MVHR retrofit isn’t DIY territory. Installation must follow a detailed specification to ensure balanced airflow, calibrated ductwork, and proper sound and thermal insulation. Once installed, the system is commissioned to verify that it performs to spec, as required by Building Regulations. This makes working with ventilation experts essential.
Key considerations for retrofit success
Throughout the MVHR retrofit process, there are a few key considerations to keep in mind to ensure a successful installation:
- Airtightness is essential: Air leakage can sabotage MVHR effectiveness. MVHR works best in homes with air permeability below 5 m³/(h·m²) @50Pa. Consider a blower door test before proceeding, and if the building is too leaky, consider adding sealing measures as part of the retrofit.
- Ductwork must be thoughtfully planned: Routing must be practical and discreet, but short, straight duct runs are best. Avoid unnecessary bends, and use acoustic insulation where needed.
- Choose the right system size: If a system is too small, it won’t ventilate properly, and if it's too large, it will waste energy. Consider using a supplier that offers system sizing as part of its design services.
- Noise and vibration control: Anti-vibration mounts and acoustic linings are must-haves for sound-sensitive areas like bedrooms.
- Ongoing maintenance: MVHR filters must be cleaned or replaced every 6–12 months, and regular servicing maintains optimum performance.
- Choose an experienced partner: Ensuring your system's long-term performance requires care and thoroughness at every stage of the retrofit process. For peace of mind, the best answer is to choose a supplier and installation partner who offers design support, installer training, and post-installation servicing.
Retrofit the right way and reap the rewards
Breathing clean, fresh air shouldn’t be a luxury; it should be part of every comfortable, healthy home. And with an MVHR retrofit, it absolutely can be. You’ll save energy, ensure occupants live more comfortably, and align your property with the necessary regulatory and building standards.
But retrofitting ventilation can be complex, so working with the right partners makes all the difference. At Titon, we’ve helped countless homeowners, landlords, and contractors with bespoke MVHR solutions that respect budgets, building quirks, and Building Regulations alike. We don’t just supply products—we design, specify, advise, and support.
We also have a network of approved service partners across the UK, who know how to install, service, and maintain Titon products for their maximum efficiency.
Whether you’re a seasoned developer or a homeowner breathing new life into a beloved old space, we’re here to help make your MVHR retrofit journey successful.
