Green Building Store is now 21°


MVHR Components

We stock a range of components for MVHR heat recovery ventilation systems including air valves, ducting, duct insulation and MVHR filters. Be sure to check out our store for products to buy.

MVHR Components

Air valves

Air valves are an important part of the MVHR system. Placed in rooms where the ducting meets the ceilings or walls, the air is extracted or supplied through them. We offer a comprehensive range of air valves to complement our MVHR systems. These are selected to carefully reduce noise, prevent drafts and ensure good air flow throughout the room.

  • Supply and extract valves
  • Wall-mounted and ceiling-mounted options
  • Directional and non-directional (ambient) options

For more technical information and advice on which air valve is best for your project, please contact our MVHR design service.

MVHR Components

Rigid ducting system

A rigid galvanized steel ducting system is often considered the premium product, providing excellent, robust and long lasting ducting system. We pride ourselves in the design and supply of these high-end systems.

  • Galvanised steel spiral wound system
  • Robust push-fit system with twin rubber seals requires no tape
  • Integrated range of acoustic attenuators

For more technical information and advice on which ducting system is best for your project, please contact our MVHR design service.

Book a MVHR design service and see how we maximise energy efficiency for you.

We’ll work alongside you and your project team to design, advise and install the most suitable MVHR unit and ducting system for your needs and budget.

MVHR Components

Semi-rigid ducting system

Typically used where space is at a premium as the ducts are typically smaller in diameter. This can mean that more ducting is required resulting in a bigger plant space.

When well designed, a semi-rigid ducting system can be as efficient as a rigid ducting system.

For more technical information and advice on which ducting system is best for your project, please contact our MVHR design service.

MVHR Components


We stock a wide range of MVHR filters to ensure the smooth running of the MVHR system. Filters are required for the MVHR units, frost protection units and kitchen extract valves. We recommend replacing these 2-4 times yearly. It is important to change filters regularly to optimise energy efficiency and comfort levels.

Where a project is in an Air Quality Management Zone (AQM) or where building occupiers have specific concerns relating to air quality, higher grade, specially designed filters can be specified to remove specific particulates from the air, such as NOX.

MVHR filters are available to buy from the 21° store, where we aim to deliver within 24-48 hours.

For more technical information and advice on which filtration system is best for your project, please contact our MVHR design service.

Shop for products you need on the 21° online store.

Browse our range of products for airtightness and specialist insulation and our MVHR filters.

MVHR Components

Heating & cooling

These devices are used to heat and cool supply air within an MVHR system. They can be electric or water-based.

  • Neat and compact heating solution
  • Heats or cools approximately 10 W/m2 of building floor area
  • Reduces the need for other heating or cooling sources

For more technical information and advice on which heating or cooling system is best for your project, please contact our MVHR design service.

Request the MVHR brochure

Discover more detail about how MVHR works, the MVHR units and components, our MVHR design service and why MVHR will bring comfort - to you and your family.

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  • Apart from keeping all the air vents clear and clean, the only maintenance is periodic filter changes. There are several filters which need to be changed to keep the air flowing properly. How frequently depends on where you live and how clean the air is. The filters keep your air clean, but are also needed to keep the system working properly. The kitchen extract filter may need changing/ cleaning more often than the others. Normally filters need to be changed every 3-6 months.

  • The F7 filter does help filter out some particulates and air pollution. However, for high traffic pollution we would recommend the addition of a NOX filter box to your MVHR system, which filters nitrous oxide from air entering the building before it goes into the MVHR intake and uses an active charcoal filter to filter out dangerous gases. If you are interested in having this additional protection, please get in touch to discuss options.

  • Although MVHR could be installed in all types of building, we generally would recommend it for buildings with good airtightness levels, for example where the air permeability of the thermal envelope is at or below 3 @50Pa. For comfort, and to reduce the carbon emissions of homes, it is important that homes have good airtightness levels, as well as good ventilation levels.

    Recent research by the Passivhaus Trust has shown that MVHR ventilation could be used in less airtight homes (eg even a fairly draughty home of 9 @50Pa) as it would still have lower carbon emissions rate than natural ventilation. However, in very draughty homes (eg higher/ worse than 9 @50Pa) the efficacy and efficiency of an MVHR will decrease.

  • When water vapour is extracted from a kitchen or bathroom it is carried along the duct to the MVHR unit where it condenses and is drained away. This is why it is important that all of the ducting is contained within the thermal envelope of the building. If the duct was cooler, the air would cool upon entering the duct and it would lose its capacity to hold as much moisture, resulting in the air condensing (warm air holds more moisture than cold air).

How can we help?

Visit the showrooms

Visit us at our showrooms in Huddersfield and Swindon or catch us at exhibitions around the UK to see our windows and doors.

Request a quote

Tell us about your project, and we'll make sure you get a no-obligation quote from us. Take a step towards a more energy-efficient home today.

Get in touch

We offer a friendly and responsive aftersales service for our windows and door ranges, with a dedicated office and on-the-road aftercare team.

Take a step towards a more energy efficient home today

From triple-glazed and alu-clad windows and doors to exceptional solutions to MVHR, it all starts with finding out your exact requirements.

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