Building Performance Evaluation (BPE) is the process of evaluating the performance of new, existing and refurbished buildings, to help the delivery of effective and efficient buildings, by informing project development, enhancing delivery, optimising performance and providing feedback. Unfortunately, however, BPE is not carried out enough and, when it does, lessons are seldom fed back into the design process for the next building.
I recently purchased an excellent book called Housing fit for Purpose by Fionn Stevenson, which, while focusing on domestic buildings, identifies challenges, and provides valuable information that can be applied to all building types. I have drawn myself a diagram illustrating the process to follow when undertaking BPE, as described in the book, which I hope to utilise for building projects I am involved with:
For BPE to be effective, it is critical that the list of auditing documents is shared early in a project to ensure the project design and delivery teams consider all relevant elements from the outset. This is a crucial point as, knowing this information is needed at the start of a project will provide focus for the production of thorough project information and good detailing. Raising awareness of the elements subject to evaluation at the project outset, will ensure more attention is paid to the quality of construction details. Anyone working on a building should have an oversight of the BPE process at project inception.
In this hugely informative book, Stevenson suggests that longitudinal BPE studies can be built into planned maintenance regimes and linked to selling or rental transactions, where they can provide real value. Embedding BPE into existing mechanisms, such as maintenance regimes, is a good way of ensuring it will happen without it being viewed as an additional activity. There is evidence that BPE has been used in this way by some housing associations to create an organisational action plan for future improvements.
One of the challenges we face in improving the performance of buildings and reducing their energy consumption, highlighted by Stevenson, is that people often choose aesthetics over building performance or energy efficiency measures. This is a behaviour that needs to change, if we are to reach net-zero emission targets.
Another issue is that houses are often assessed as having a 60-year lifespan, but this doesn’t always reflect reality where houses can often last for hundreds of years. This point was also made by Robyn Pender of English Heritage in a recent presentation I saw, who (when discussing carbon in buildings) talked about traditionally built houses that were designed with good environmental design principles, such as natural ventilation, thermal mass and protection from glare and overheating; and were constructed using local materials in vernacular styles – i.e. offering low carbon solutions for buildings. She stated that we can learn a lot of lessons from historic buildings and finished her presentation with a quote: “The future lies in lessons of the past”, and a warning that we are perhaps overcomplicating our modern buildings with the inclusion of too many services and controls. Something for us all to think about.
Another element discussed in the book is the need to create a virtuous circle of learning through participatory action research, where building occupants take part in informing the BPE process. This is akin to my ‘Active Learning Loop’, which I developed in an earlier doctorate module to illustrate the need for continuous learning in the successful roll out of Active Buildings. Or Deming’s Plan-Do-Check-Act Cycle, used in manufacturing.
BPE should be mandated on all building projects and, importantly, the data collected during BPE must be used to learn from and to make improvements. This is a fundamental part of the work we are doing at SPECIFIC and the Active Building Centre, where we are constantly learning from the plethora of data we collect from our Active Building demonstrators; and using the learning to improve both the existing buildings and the knowledge we impart to others for future building projects.