Updates to Part L (conservation of energy and power) and F (ventilation) of the building regulations come into force today, 15th June 2022, along with the launch of the new Part O (overheating) approved document.
The Part L changes usher in tougher targets and new compliance metrics along with a significant adjustment in carbon factors for fuels. New dwellings built to the interim standard will produce 31% less CO2 emissions (on aggregate) than those built to the previous standard. Non-domestic buildings will produce 27% less CO2 emissions relative to the outgoing (Part L 2013) compliance target. Fabric energy efficiency targets for new dwellings are more onerous than ever before and the Primary Energy Rate metric considers not only energy used within the building itself, but also the amount of energy required to produce the fuel source in the first place.
The update signals a step change for energy efficient design in new build developments, with significant impacts on both build cost and design considerations.
The energy compliance shift is supported by amendments to building regulation Part F to ensure ventilation strategies correlate to new design criteria. Furthermore, overheating assessment is now removed from Part L of the regulations to enable a more detailed focus on this increasingly significant issue.
The Government’s New Approved Document, Part O (Overheating) looks specifically at addressing this issue of overheating in new build homes and offers two distinct compliance options:
- The Simplified Method: this prescriptive method considers the size and orientation of glazing and compares the glazing area to the floor area. Window opening areas are also considered, to deliver suitable ventilation.
- Dynamic Thermal Analysis (CIBSE TM59): this can be used to ensure dwellings comply with the document by predicting the risk of overheating and offering a range of strategies for reducing this risk and offers more latitude in the design approach.
The Element Sustainability team includes qualified and experienced energy assessors who would be pleased to answer any queries you may have. If you would like to discuss the implications for your project, please get in touch!