Understanding ventilation practices in low energy homes

By Carrie Behar

Supervisors:

Tadj Oreszczyn

Ben Croxford & Lai Fong Chiu

2011 - 2015

A range of new ‘whole house’ ventilation technologies are currently being introduced into new housing, in response to the UK’s drive to improve the energy efficiency of its housing stock. However, the growing awareness of the important role that occupants’ ‘behaviour’ plays in the final energy consumption of a dwelling leads us to question the notion, steeped in technological determinism, that simply changing the type of ventilation will drive down energy use.

This research investigates how residents engage with the various components of a ‘sustainable’ ventilation system through their everyday domestic practices. These components include boost switches, trickle vents, windows, doors and extract fans. The data is analysed to explore how residents’ practices within the home might be either deliberately or unintentionally ‘constrained’ or ‘enabled’ by the physical, social and temporal configuration of domestic spaces, a process which begins at the design and procurement stage, long before the final residents are selected.

The work also questions to what extent we can (or should) distinguish between specific ‘ventilation practices’ or whether the act of replacing old stale air with new fresh air is in fact a by-product of a multitude of other, often interconnected, practices relating to the end goals of staying safe, maintaining thermal comfort and homemaking.

A qualitative methodology was adopted, using in-depth interviews, resident walk-throughs, and photography, supported by analysis of design and construction documentation, at three recently completed social housing schemes: the first naturally ventilated, the second incorporating mechanical extract ventilation and the third utilising mechanical ventilation with heat recovery. The fieldwork was conducted in 2013 and comprised 15 resident interviews and 13 further interviews with the architects and contractors responsible for delivering each scheme, as well as management and sustainability representatives from the housing associations who commissioned the projects and now act as landlords.