DOMESTIC VENTILATION
www.heatingandventilating.net “T
How to meet latest ventilation requirements in new homes
he updated Approved Document F regulations, which were introduced in June 2022, reflect the growing
importance of effective ventilation solutions, particularly as homes become increasingly airtight. Prior to the 2022 update, Approved Document F
was a single document that primarily addressed ventilation in new dwellings. It provided limited guidance on non-residential buildings and was supplemented by the Domestic Ventilation Compliance Guide. This often led to confusion and inconsistencies in interpretation. The revised Approved Document F is made up
of two volumes: Volume 1: dwellings and Volume 2: buildings other than dwellings. In addition, the Domestic Ventilation Compliance Guide has been integrated into the main document, streamlining the information and making it more accessible.
Updated Building Regulations
Some of the most significant changes in the latest updates included: ¡ Renaming of ventilation methods for clarity. ¡ Increased whole dwelling ventilation rates. ¡ Modified requirements for background ventilation. ¡ Introduction of specific guidance for existing dwellings. ¡ Additional focus on indoor air quality and volatile organic compounds (VOCs). The increased whole dwelling ventilation
rates specified in the 2022 update require a more rigorous approach to system design and specification. For a one-bedroom property, the minimum ventilation rate has risen from 13 l/s to 19 l/s, a significant increase that may require upgrading to more powerful or efficient systems. These changes reflect a more holistic approach
to ventilation, acknowledging the interconnected nature of air quality, energy efficiency and occupant health.
Mechanical ventilation with heat recovery (MVHR)
Mechanical ventilation systems, such as Mechanical Ventilation with Heat Recovery (MVHR) and Mechanical Extract Ventilation (MEV), play a crucial
28 June 2025
Ruth MacEachern, product manager at EnviroVent, looks at how to ensure compliance with the latest ventilation requirements in new homes, as part of improving indoor air quality
role in achieving good quality indoor air quality in a home.
MVHR systems, previously known as System 4, offer the most comprehensive approach to whole- house ventilation. These systems extract stale air from wet rooms and supply fresh, filtered air to habitable rooms, while recovering heat from the extracted air, which significantly reduces energy losses and heating costs. The benefits of MVHR systems are that they offer
excellent control over indoor air quality and can provide significant energy savings in well-insulated homes. They can also effectively filter incoming air, reducing allergens and pollutants. Although the initial outlay with MVHR may be higher than for MEV systems, these systems do offer an enhanced level of ventilation performance, ensuring very good levels of indoor air quality
throughout a property. As buildings become more airtight to improve
energy efficiency, the risk of poor indoor air quality increases. Striking the right balance between conserving energy and providing adequate ventilation is crucial.
Continuous mechanical extract ventilation (MEV and d-MEV)
Previously referred to as System 3, MEV systems provide continuous low-level extraction of air from wet rooms, with the option for boost speeds when required. Decentralised MEV (d-MEV) operates through individual fans in each wet room, offering greater flexibility in installation and maintenance. MEV systems have many benefits, including providing a consistent level of background
DOWNLOAD THE HVR APP NOW
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36
