Post Occupancy Evaluation, POE, is the practice of monitoring buildings once they are handed-over to clients, to check that the environmental performance in use relates to how the building was designed to perform. There is typically a massive gulf between the two. This happens for a variety of reasons, user behaviour being the most common, but also poor design and poor construction. Low energy buildings can often be overly complicated, leading to higher energy consumption and poorer comfort than is necessary.
Traditionally, designers do not look back at buildings they have designed. Once the snaglist is complete, which would cover one year of occupancy, there is no impetus to follow up how the building is performing. You might expect one year to be enough to deal with improper use or design/construction faults, but the reality is that the feedback in these cases is based on anecdotal client reports. A client in a commercial building may be 200 people, all with different preferences, different occupancy regimes, different locations within a building. And buildings have micro-climates – just ask people in an open plan office where some are beside an openable window, others are not, some in direct sunlight, east facing, others deeper within the plan with a different aspect.
POE is the practice of installing devices which measure absolutely the factors which determine comfort, so these are typically temperature and relative humidity, but could also take into account solar gain, the operation of openable windows and actuators, ventilation systems and heating/cooling systems where required.
The gathering and analysis of the empirical data then allows the designer to develop a full picture of how the building is mitigating external factors and what conditions are arising inside. This can then be judged against reported perceptions of comfort and measure energy consumption.
In passivhaus architecture, this is especially important, because passivhaus is not just an energy performance target, it is a guarantee of comfortable conditions also. And it is up to designers to prove to others that the system works.
For this reason, we are conducting POE on Ireland’s first PassivHaus Pharmacy in Clonmel. Completed this summer, we will record internal and external temperatures and humidity, and record when the heating system is required. From this information, we can help the client to adapt to using their new premises, so that it works with them to produce perfect conditions for their customers, staff and minimise their overheads to maximise profit. This information can be disseminated academically so that others can learn from our triumphs and mistakes.
Adrian Leaman of Usable Buildings deserves all credit for inspiring architects to engage with POA. Without doubt, during my Masters studies in Advanced Energy and Environmental Studies at the Centre for Alternative Technology, Adrian’s lecture was the most memorable, enjoyable and inspiring.