Energy Efficient
Ventilation Systems
In a well-insulated building, ventilation heat loss accounts for 40–60% of the remaining energy demand. Getting ventilation right is no longer just a compliance issue — it is central to achieving net zero targets, improving EPC ratings and cutting energy bills for your occupants.
Where Does the
Heat Actually Go?
When homes were draughty, ventilation heat loss was often less than fabric heat loss — so insulation was the priority. Now that wall, roof and window insulation standards are far higher, ventilation has become the dominant source of heat loss in well-upgraded homes. An MVHR system addresses this directly by recovering up to 95% of the heat in extracted air before it leaves the building.
- Ventilation = 40–60% of remaining heat loss in EPC Band A/B homes
- MVHR recovers up to 95% of this heat — equivalent to nearly eliminating the loss
- Running costs typically £25–60 per year in electricity (EC motor fan units)
- Simple payback period 4–12 years depending on building size and energy tariff
- EPC rating improvement — SAP/RdSAP credits MVHR systems directly
- Passivhaus standard requires MVHR — the global benchmark for low energy buildings
Measurable Energy Performance Gains
Lower Energy Bills
A typical three-bedroom house with MVHR will save between £150 and £400 per year in heating costs compared to the same house with trickle vent and extract fan ventilation — based on current gas tariffs and an 85% efficient heat recovery unit operating at design conditions.
EPC Rating Improvement
SAP 10.2 (and the emerging SAP 11 methodology) includes specific credits for heat recovery ventilation. Switching from a simple extract system to MVHR can improve a dwelling's SAP score by 4–10 points — potentially enough to move from Band C to Band B, which can add value and meet minimum energy efficiency standards for rental properties.
Carbon Reduction
With the UK grid increasingly decarbonised, the small electrical load of an MVHR fan (typically 20–60W) has a very low carbon footprint. The heat energy saved from recovering warm exhaust air far outweighs the carbon cost of powering the unit — resulting in a strongly positive carbon balance over the system life.
Passivhaus & Net Zero Ready
Passivhaus — the world's most rigorous low-energy building standard — mandates MVHR for all certified projects. If you are building or retrofitting to Passivhaus, EnerPHit, or a net zero operational carbon brief, MVHR is not optional. Chillmasters has experience specifying and installing MVHR for Passivhaus-informed projects in the North West.
What Does It Cost
to Run?
Modern MVHR units use electronically commutated (EC) brushless motors that consume very little electricity. At typical continuous low-flow settings, most domestic units draw 20–40W. Running costs work out at approximately £25–60 per year at current electricity prices — less than a single room electric heater left on for a few hours each week.
- EC motor units: 20–60W at design flow — exceptional efficiency
- Annual electricity cost: approximately £25–60 at current tariffs
- Filter replacement: £20–50 per year depending on unit and filter grade
- Annual service: from £120 — covers filter change, flow check and inspection
- System life expectancy: 15–25 years with correct maintenance
EPC Assessors
& New Builds
If you are an EPC assessor, developer or architect working on a SAP calculation, we can provide the data inputs you need to correctly model an MVHR system. This includes measured specific fan power (SFP), confirmed heat recovery efficiency, and the commissioning data required to demonstrate that the installed system matches the design specification.
- Specific fan power (SFP) measurement for SAP data entry
- Confirmed heat recovery efficiency at test conditions
- Commissioning report confirming installed vs design flow rates
- Support for RdSAP assessors carrying out EPC on existing dwellings post-install
- Available for developer handovers, new build certification and retrofit EPC uplift
Related Services
Air Conditioning
Installation, servicing and repairs for domestic and commercial air conditioning.
Refrigeration & Cold Rooms
Cold room design, commercial refrigeration and emergency breakdown response.
HVAC Design & Consultancy
Load calculations, system specification and project management for HVAC projects.
Electrical & Plumbing
Power supplies, pipework and electrical services supporting HVAC installations.
Compliance & Maintenance
PPM contracts, F-Gas compliance, TM44 surveys and reactive maintenance.