English Housing Survey Shows Alignment with Part O Requirements

The latest English Housing Survey (published July 2023) indicates that occupant overheating experience aligns with the requirements of Part O:

• Only 49% of households were able to keep homes cool using windows alone. This supports our experience of Part O modelling, where additional measures are commonly required;
• Part O requires the use of passive measures as far as reasonably practicable, hence developers should be prepared to implement these prior to consideration of non-passive means;
• 7% of households did not mention the opening of windows to cool down their homes at all. This may be reflective of noise/air quality/security risk issues highlighted in Part O. Whilst not broken down geographically, this number is likely to be higher in urban areas; and
• We currently expect any developments affected by noise/air quality/security risk to require peak-lopping MVHR or comfort cooling.

It is also worth considering strategies to reduce risk (such as sound barriers on site borders with noise sources, e.g., railway lines) or effective communication to occupants on how to reduce overheating (such as through Home User Guides). Following up with post occupancy evaluation is effective for confirming the success of strategies implemented.