New homes in the UK are more airtight than ever. As building standards push for higher energy efficiency, the days of draughty walls and heat-leaking windows are gone. But with better insulation and low permeability comes a challenge: how to ventilate a home that no longer breathes.
New homes in the UK are more airtight than ever. As building standards push for higher energy efficiency, the days of draughty walls and heat-leaking windows are gone. But with better insulation and low permeability comes a challenge: how to ventilate a home that no longer breathes.
Mechanical Ventilation with Heat Recovery (MVHR) is now a key feature in modern home design. Not only does it meet new ventilation requirements under Part F and Part L of the Building Regulations, it also helps achieve SAP targets, supports EPC ratings, and improves indoor air quality.
At ClimateWorks, we design and install MVHR systems for new developments across Basingstoke, Woking, Reading, West London, and other growing urban hubs. In a market where energy ratings matter to both developers and homeowners, MVHR is not just a nice-to-have—it’s a necessity.
Building Regulations in the UK are changing how homes are built. Tightened standards under Approved Document F (ventilation) and Approved Document L (energy conservation) mean that uncontrolled ventilation, such as window trickle vents or passive ducts, no longer satisfy compliance in most new builds.
When a home achieves air permeability under 5 m³/(h·m²) @ 50 Pa—which is common in new construction—it must use continuous mechanical ventilation, and ideally with heat recovery, to meet legal ventilation targets.
In other words, if you're building new homes that are well-insulated and airtight (as nearly all are), you need MVHR to comply with the law and provide proper indoor air quality.
Part F of the Building Regulations sets out the minimum fresh air requirements for new dwellings. MVHR is listed under System 4, which requires:
Systems must also meet noise performance, have accessible filters, and include controls that are user-friendly.
Part L requires buildings to conserve energy. MVHR supports this by recovering 85–90% of the heat from outgoing air, helping reduce the space heating demand and improving the Dwelling Emission Rate (DER).
New SAP 10 methodology includes the benefits of MVHR in its calculations, meaning it contributes to:
A developer constructing 12 energy-efficient homes in Wokingham wanted to futureproof the properties for Part F compliance and sustainable performance. The build featured:
ClimateWorks was brought in at the design stage to integrate MVHR into each unit. Our approach included:
The result was full compliance, improved SAP scores, and greater long-term appeal for buyers focused on energy performance and air quality.
While extract-only fans may be suitable for older homes, they fall short in new builds with high levels of airtightness. MVHR systems are now the go-to option for high-performance new homes due to their:
Installing MVHR is not a plug-and-play job. We offer end-to-end services that ensure every unit is installed and commissioned in line with Building Regulations and site-specific goals.
We currently install MVHR systems in new homes across:
Our familiarity with local Building Control teams ensures your project moves forward without costly delays or compliance failures.
✔ Has airtightness been measured or modelled?
✔ Are there trickle vents or passive vents?
✔ Will the property meet SAP 10 energy standards?
✔ Are duct routes planned into floor or ceiling voids?
✔ Is the system specified and sized for the property?
✔ Has commissioning been scheduled as part of the build programme?
If the answer to any of these questions is unclear, MVHR should be addressed at the earliest design stage—not left to the final fitout.
We install and commission MVHR systems across the South East. If you're developing homes in Hampshire, Berkshire, Surrey or Greater London, we can help you:
👉 Contact ClimateWorks to discuss your new build project
Explore the benefits of working with certified MVHR specialists from design to handover.
[1] GOV.UK – Approved Document F: Ventilation
https://www.gov.uk/government/publications/ventilation-approved-document-f
[2] GOV.UK – Approved Document L: Conservation of Fuel and Power
https://www.gov.uk/government/publications/conservation-of-fuel-and-power-approved-document-l
[3] NHBC – Mechanical Ventilation with Heat Recovery in New Homes
https://www.nhbcfoundation.org/publication/mechanical-ventilation-with-heat-recovery-in-new-homes/
[4] Energy Saving Trust – Whole House Ventilation
https://energysavingtrust.org.uk/advice/ventilation/
Dr. Julian Carter is a highly experienced thermal systems expert with over 15 years in the field, holding a PhD in thermal systems. His career spans academic research, consulting, and teaching, focusing on air conditioning and refrigeration systems. Dr. Carter bridges the gap between theoretical advancements and practical applications, providing expert insights to organisations like ClimateWorks, where his guidance informs decision-making and industry best practices. Notably, he has worked on international projects with organisations such as Daikin Industries, the International Institute of Refrigeration (IIR), and the United Nations Environment Programme (UNEP). Currently a lecturer at Edinburgh University, Dr. Carter combines his expertise with a passion for educating the next generation of engineers and advancing climate control technologies.