An MVHR installer is a specialist in Mechanical Ventilation with Heat Recovery systems - the balanced whole-house ventilation strategy used in Passivhaus and highly airtight new build dwellings. An MVHR unit extracts stale, humid air from wet rooms and kitchens, passes it through a heat exchanger, and supplies fresh filtered air to living spaces and bedrooms, recovering 85-95% of the heat in the process. Under Part F of the Building Regulations, ventilation must be designed to meet minimum flow rates; MVHR is the preferred strategy for new builds with very low air permeability targets.
What they do
- Air flow and ventilation rate calculations to meet Part F
- Duct layout design and specification
- MVHR unit selection, mounting and installation
- Ductwork installation, insulation and sealing
- Commissioning and balancing to achieve design air flow rates
- Part F compliance testing and air flow rate documentation
- Integration with the building's air tightness strategy
- Annual filter replacement and maintenance
When you need one
An MVHR installer is needed on new builds or major renovations targeting high airtightness where natural ventilation alone would cause condensation and poor air quality.
Typical costs (UK, 2025)
| Job type | Typical cost |
|---|---|
| MVHR unit (supply only) | £800 - £2,500 |
| MVHR installation labour | £1,500 - £3,500 |
| Full supply and install (3-bed house) | £3,000 - £6,000 |
| Commissioning and balancing | £300 - £600 |
| Annual maintenance service | £150 - £250 |
| Duct cleaning | £200 - £400 |
Costs vary significantly by house size, duct run complexity and unit specification. Commissioning and balancing are not optional - they are required for Part F compliance.
Qualifications to look for
The BPEC MVHR qualification covers system design, duct layout, installation and commissioning. It is the primary trade qualification for MVHR installers in the UK.
City and Guilds ventilation qualifications including the 6187 domestic ventilation assessment are held by specialist MVHR installers and ventilation engineers.
Installers working on Passivhaus projects should understand the Passivhaus standard's ventilation requirements and ideally hold or work under a Certified Passivhaus Tradesperson qualification.
How to find a reputable MVHR installer
Frequently asked questions
Does every new build need MVHR?
No - Part F allows four ventilation strategies: natural ventilation, MEV (mechanical extract), MVHR, or mixed-mode. MVHR is required if the design target air permeability is below about 3 m3/hr/m2 at 50Pa to avoid condensation issues.
How does MVHR save energy?
The heat exchanger recovers 85-95% of heat from stale extracted air and transfers it to incoming fresh air. In a well-insulated house this can save £100-300/year in heating costs.
Can MVHR be fitted in an existing house?
Yes but retrofit is complex and expensive due to ductwork routing through existing ceilings and walls. It is best specified at design stage. A ducted MEV system is often more practical for retrofit.