Healthy housing depends on effective post-occupancy evaluation
In our latest guest blog Fionn Stevenson, professor of sustainable design at the University of Sheffield, makes the case for research and evidence-based design, including once houses are occupied, in building healthier and more sustainable homes.
Given the increasingly rapid changes occurring in our environment due to climate change and the new technologies associated with improving housing, there has never been a greater need for evidence-based housing design. It would be unheard of for medical practice not to be continuously informed by research. Yet, in housing, we routinely deliver projects without adequate research based on previous performance. We think we know our housing, but how many of us have moved beyond the customary resident survey to really try to understand the integrated socio-technical reasons underlying poor performance, by commissioning this type of feedback?
Around 4.5 million UK homes overheat the summer, with poor indoor air quality and mould, which are clearly linked to increases in asthma, while new housing routinely uses twice as much energy as it was designed to use, resulting in excessive carbon emissions rather than the planned reductions. Expert help, using tried-and-tested, performance-proven technologies, can ensure our housing designs address these issues appropriately. Existing research shows how to design these problems out from the beginning, but it is often simply not used – and instead residents are blamed for ‘poor understanding’ and ‘inappropriate behaviour.’
My own research highlighted the overheating of timber homes due to poor designs in Scotland 15 years ago and gave recommendations for solving this through adequate ventilation and external shading. My new book - Housing Fit for Purpose: performance, feedback and learning - sets out a way forward for the housing sector, based on decades of measuring and evaluating housing performance and seeing the subsequent recommendations fundamentally improve the housing lifecycle.
Post-occupancy evaluation (POE) which combines social and technical feedback is clearly articulated in RIBA’s 2013 plan of work. Yet just 19% of UK architecture practices offer it as a service. Even fewer housing clients use it. Many are put off by myths concerning the cost and complexity of POE, fearing a risk to their indemnity and reputation, leading to litigation and costs. But it’s far better to know sooner if there are real performance issues with your housing compared to the design intentions and to use POE for risk avoidance and mitigation, thus preventing cost overruns. When POE reveals defective workmanship, poor commissioning of equipment and other issues at the end of the usual one-year liability period for contractors following contract completion, these can be promptly and discreetly addressed. The findings can then be used to improve housing practice and increase resident and staff confidence and satisfaction.
Right now, POE is held back because clients and design teams believe it is simply an ‘extra’ service when it should be automatic. POE costs should be built in from the start of any project, not bolted on at the end when there is no budget left. The good news is that RIBA has now recommended that all its member practices offer POE to their clients, with this probably to become a professional requirement within a year. RIBA is also quite clear that their members are covered by professional indemnity to carry out POE. And it need not be that expensive to do a light-touch POE to start with – less than 1% of overall project costs, potentially saving far more.
Housing degree programmes and CPD in the UK currently lack any focus on developing even the most basic understanding of POE, which makes it hard for housing managers and clients to know what to ask for and what to expect. More POE CPD from CIH would clearly help here!