Understanding Mechanical Ventilation with Heat Recovery (MVHR)

Mechanical Ventilation with Heat Recovery (MVHR) is a game-changer in indoor air quality, acting as an efficient building ventilation system. 

At RHW, our MVHR systems provide constant air movement, replacing polluted air with filtered fresh air and ensuring an energy-efficient building environment.

The Significant Role of MVHR in Indoor Air Quality

MVHR is no longer a luxury but a vital component nowadays in maintaining superior indoor air quality. 

It advances air tightness targets, eliminates the need for trickle vents and overcomes the shortcomings of natural ventilation. Through a heat recovery ventilation system, MVHR extracts moist, stale air throughout a building and replaces it with filtered, tempered air, contributing to a healthy and comfortable indoor atmosphere.

What is MVHR?

A Mechanical Ventilation with Heat Recovery system, or MVHR, is a building ventilation system that combines energy efficiency with top-tier air quality.

The principle of MVHR uses a simple yet effective method of extracting stale air from a building and replacing it with fresh, filtered air.

It ensures constant air movement and improved air quality within a home or other building. It also plays a significant role in maintaining the building regulations for air tightness targets.

How? Through a controlled ventilation mechanism that reduces the need for uncontrolled ventilation, such as trickle vents or window vents.

The big highlight of MVHR systems is their ability to recover heat from the extracted air and use it to temper the incoming fresh air – contributing to energy-efficient buildings.

These systems are super efficient, especially during the cold season, providing a comfortable indoor climate while minimising heating demand.

MVHR meets Building Regulations for new properties under System Four of Building Regulations Part F.

How does MVHR work?

How MVHR works The MVHR system, or Mechanical Ventilation with Heat Recovery, is a building ventilation system that operates based on a balanced supply and extract principle.

Its functionality centres around a heat exchanger unit responsible for recovering heat. 

This unit, often housed within utility rooms, extracts stale air, often laden with pollutants and moisture, from wet rooms like bathrooms and kitchens. It simultaneously supplies fresh, filtered air into living rooms, bedrooms, and other habitable spaces.

MVHR systems are efficient because they extract the heat from rooms in your home that naturally generate more heat. 

For example, at home:

  • The bathroom often generates heat when you run a hot bath or a hot shower
  • The kitchen generates additional heat every time you use the oven or the hob

This heat can then be distributed throughout your home using an MVHR system.

Because they provide constant ventilation in damp areas throughout a building, they prevent moisture in the air from settling on surfaces and causing damage.

By doing so, MVHR systems effectively prevent common problems caused by excess moisture, such as condensation build-up and mould growth, in homes and other buildings.

When your MVHR system detects a change in air humidity levels, it will automatically boost operation to bring the humidity down to target levels.

MVHR systems can eliminate condensation, mould and more serious structural issues that dampness can cause.

They also significantly improve the air quality in the building because they constantly extract dampness and pollutants in the air and supply the building with fresh air.

MVHR systems are energy efficient and easy to run, only requiring a brief filter change once every 6 to 12 months.

The Benefits of MVHR

Unmatched Indoor Air Quality

Experience the best indoor air quality with our MVHR systems. They significantly reduce pollutants and allergens, creating a healthier living or working environment.

Uncompromised Cleanliness

Don’t let dust and pollutants compromise the purity of your indoor air. Our MVHR units filter out these nasties, maintaining a clean and healthy indoor atmosphere. From the tiniest dust particles to various pollutants, the efficient filtration system takes care of them all.

Perfect Humidity Control

Moist air indoors can lead to mould and dampness. Our advanced MVHR systems offer an excellent solution for humidity control. Each system supplies constant ventilation, extracting moist air and replacing it with fresh, dry air, preventing the build-up of damp conditions.

Ultimate Comfort

Imagine your building with a constant supply of fresh air, creating a comfortable and refreshing environment. Our MVHR units with heat recovery ventilation offer just that. They promote constant air movement, ensuring that every corner of the space gets an adequate supply of fresh air.

Exceptional Energy Savings

With the rising energy costs, an energy-efficient solution is more of a necessity than a luxury. Our MVHR systems offer the most efficient heat recovery, saving money on energy bills. The systems retain the heat from the outgoing, polluted air, resulting in lower heating demand and considerable energy savings.

Why do I need MVHR?

Ever noticed how new homes and buildings are becoming more airtight with insulation, draught-proofing and double-glazing? This air-tightness traps moisture inside from everyday activities such as cooking, washing, and even breathing. With nowhere to go, this moisture clings onto cold surfaces like windows or exterior walls, leading to condensation, dampness and mould, resulting in inferior Indoor Air Quality (IAQ). 

Don’t let your air quality degrade. MVHR is your solution to a healthier, more comfortable indoor environment.

An MVHR unit continuously ventilates a property, meaning that everyday moisture doesn’t gather on surfaces – it is extracted to the outside, eliminating the risk of structural and cosmetic damage caused by condensation and mould.

MVHR systems are also super efficient and recover up to 91% of heat lost through extraction, transferring that heat to incoming air.

When is MVHR Recommended?

MVHR systems help achieve highly energy-efficient buildings, especially those with high air-tightness targets.

These systems ensure controlled ventilation, constant air movement, and excellent indoor air quality without heat loss.

They are particularly beneficial in environments with high moisture levels, continually extracting moist air and supplying fresh filtered air.

MVHR systems also address concerns of polluted air in urban areas, purifying incoming fresh air before distribution.

In short, MVHR is a reliable solution for achieving energy efficiency, improved air quality, and cost-effective heating system design.

MVHR Applications

  • Educational Institutions: Schools, Colleges and Universities
  • New Build Homes
  • Residential Buildings: Houses and Apartment blocks
  • Commercial Buildings: Offices, Retail Spaces, Hotels
  • Data Centers: Server Rooms
  • Local Authority Public Buildings: Libraries, Museums, and Cultural Centres
  • District Heating
  • Healthcare Facilities: Hospitals and Clinics
  • Residential Care Facilities: Nursing Homes and Assisted Living Facilities
  • Leisure Facilities: Gyms, Spas, and Recreational Centres
  • Farms
  • Commercial units

Choosing an MVHR system

Introducing the right MVHR system for your building:

  • Consider the size of your building and the number of occupants for an appropriately sized system
  • Prioritise efficiency for year-round comfort and reduced heating costs
  • Look for filters that enhance indoor air quality by removing pollutants and allergens
  • Opt for flexible ducting and branch systems for easier installation and heat retention

Get a FREE quote from RHW to help you choose wisely and enjoy optimal performance, energy savings, and healthier indoor air.

Why Choose RHW?

  • Decades of Expertise: Trust in our 10+ years of industry experience and hundreds of successful MVHR projects.
  • Quality Partnerships: Benefit from our strong affiliations with leading manufacturers – Stiebel Eltron and Mitsubishi ECODAN, ensuring reliable products with 7-year guarantees.
  • In-house Design: Rely on our single-point responsibility for design, meeting MCS standards for a full range of services vital for government renewable heat scheme claims.
  • Coordinated Project Management: Our operations team expertly integrates with your building schedule, coordinating with contractors and tradespeople for seamless project delivery.
  • End-to-end Solutions: Enjoy comprehensive coverage of your renewable heating installation needs – we do it all, from initial design to handover.
  • Proven Track Record: RHW has a proven track record in delivering hundreds of successful, efficient, cost-effective MVHR solutions.
  • Tailored MVHR Solutions: Our experts will work to create a tailored solution specific to your unique needs, ensuring optimal performance in your property.
Stu S SmithStu S Smith
11:25 19 Dec 23
I highly recoment Owain and his team
carwyn reescarwyn rees
20:10 11 Dec 23
A very professional business with an extensive knowledge of various renewable installations and the quality of the workmanship, tidiness and support is highly commended. I would highly recommend this firm.
Liam PhillipsLiam Phillips
20:23 06 Nov 23
The team behind RHW are brilliant, kept in the loop with weekly updates will use again on new projects.
20:19 02 Aug 23
Owain & his team are 1st class , everything is explained in detail workmanship is on point , and all waste disposed of.
Mukesh VarsaniMukesh Varsani
21:26 23 Mar 23
Highly recommend to choose Rhi they were brilliant. Full explenation on system they were prompt tidy and we are so happy we had Owian and his team to do the install in our house. 10/10
Gareth DaviesGareth Davies
08:12 10 Mar 23
Really pleased with RHW. They started work as planned did not leave the job until it was finished. They worked in a clean and tidy professional manner . The air source heat pump that was installed has worked perfectly and has no problem in keeping the house warm together with plentiful hot water
King JonesKing Jones
16:11 18 Nov 22
April 2022, our gas boiler started playing up and so we had to look for a replacement. My brother-in-law had recently installed an air source heat pump by this company which seemed to be the way forward. Renewable Heating Wales provided us with a quotation and a time to carry out the installation. They started the work on a Tuesday by removing the old gas boiler system and water tank. The new system was fully up and running by Friday midday.A very professional installation and we can highly recommend them.

Frequently Asked Questions

MVHR stands for Mechanical Ventilation with Heat Recovery, a modern ventilation system that can ventilate homes and buildings while protecting the property from heat loss.

MVHR systems provide effective and efficient ventilation without incurring significant running costs. MVHR is an environmentally friendly alternative to opening doors and windows to ventilate a property. And there is no need to turn up the heating to compensate for the heat lost outside the home.
MVHR systems are available in different sizes depending on how large the building you want to ventilate is and the space available for installing an MVHR unit and ducts. These days, many new homes have inbuilt MVHR systems. But you can also retrofit an MVHR unit to an older home or building.

As well as allowing homeowners and building managers to manage ventilation and air temperature, MVHR systems give users control over indoor air humidity levels. An MVHR system is one of the simplest and most efficient ways to manage air quality throughout a building without losing heat and energy. Installing an MVHR system in your home or commercial building could save you money on energy bills and also improve comfort levels throughout the property.

One of the biggest obstacles to installing an MVHR system in a home is how much it costs. While MVHR systems are very efficient to run and often help reduce energy bills long term, the upfront installation costs may be a lot for some homeowners. You must factor in the cost of installing your MVHR system before you commit to an MVHR. You may be eligible for a loan to help cover the cost of financing an MVHR installation.

There are a lot of variables involved in calculating the cost of an MVHR system, which makes it hard to give an estimated cost without knowing the specific details of your circumstances. The average cost to install a residential MVHR system is around £6,000 to £7,000.

Some of the factors that could affect the cost of installing MVHR include:

  • Whether retrofitting a system to an existing property or fitting a system into a newly built property, which is usually easier
  • The layout of the home and how complex the installation is
  • The size of the home
  • How easy pipework is to access
  • The amount of rebuilding or renovation work required after the installation
  • The energy needs of the home

Generally, the costs of installing an MVHR system consist of design costs, component costs, and installation costs. 

The MVHR unit costs around £3,000 on average for a domestic unit and £10,000 for a commercial unit. The installation costs for large commercial properties and offices are typically higher than those for residential properties.

Maintenance costs are another consideration when evaluating the total cost of an MVHR system. Regular replacement of filters and checking the air tightness ensures optimal performance and longevity of the system.

Despite these costs, remember that an MVHR system provides constant ventilation, transferring heat from the extracted air back into the incoming fresh air. This process minimises heating demand, making your home’s heating system more cost-effective in the long run.

Are you considering installing an MVHR system in your home or commercial building? You must ensure that your MVHR is as efficient as possible and serves your property’s needs well. Work with professional designers and installers to create an MVHR design suited to your building’s energy needs. Having your system professionally installed also guarantees that it works properly and performs as it should to minimise heat loss and maximise energy efficiency.

Many things at the design stage can help maximise the efficacy of an MVHR system. For example, any concern about excessive system noise can mitigated when drawing up designs. Ask your MVHR designer to model the sound levels the MVHR will emit and check how audible the sound is in each room. Then, you can add bigger silencers to the ducting system to minimise the sound levels if needed.

Also, consider the property’s unique features before designing the MVHR system. Consider where the unit and ducting system will fit and how your building may have to be adapted to accommodate the new unit. Professional designers should consider all these aspects when drawing up custom MVHR designs and use 3D modelling software to ensure the MVHR unit is a perfect fit for the building, no matter how old it is.

Indeed, retrofitting an MVHR system into an existing building is feasible, though it presents a unique set of challenges. The process requires a comprehensive understanding of the building’s existing ventilation, heating system design, and thermal envelope. Meticulous planning can ensure the MVHR unit and ducting system integrate efficiently.

Key considerations for retrofitting an MVHR system include the building’s air tightness and potential internal obstructions. An MVHR operates optimally in energy-efficient buildings that comply with air-tightness targets. So, renovations may be necessary to improve air tightness and ensure the MVHR system functions efficiently.

Furthermore, internal obstructions can impact the placement and function of the MVHR unit. Thoughtful design and proper placement of the unit, ducting system, and vents are crucial to ensure constant air movement and efficient heat recovery.

While retrofitting an MVHR system is not without its challenges, the benefits of improved air quality through filtered fresh air, energy efficiency, and constant ventilation can significantly enhance the comfort and health of the occupants.

MVHR systems help level out temperatures between rooms, creating a more uniform and controlled environment in your home. By extracting stale, warm air and recovering the heat, these systems warm incoming fresh, filtered air for distribution. With constant air movements and balanced ventilation, every room can enjoy a comfortable temperature, regardless of external factors. 

An MVHR system ensures improved air quality, energy efficiency, and temperature control, making it an effective whole-building ventilation solution.

Overall, with an efficient MVHR heat recovery ventilation system in place, you can expect significantly improved air quality, energy efficiency, and temperature control, all while maintaining the high air tightness targets of modern, energy-efficient buildings. An MVHR system is a whole house ventilation system and works to ventilate the entire building – and occupants will enjoy its many benefits.

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