Emerging themes from Innovate UK’s BPE programme

This blog was written by Peter Tse, Principal Design Consultant for BSRIA’s Sustainable Construction Group

Back in May 2010, Innovate UK (formally TSB) embarked on four year programme, providing £8m funding to support case study investigations of domestic new build and non-domestic new build and major refurbishment projects.  In total the programme has supported 100 successful projects to provide a significant body of work, that provide insights on the performance of various design strategies, building fabric, target performances, construction methods and occupancy patterns, handover and operational practices.  This work will be shared across the industry providing evidence based information, increasing industry understanding to support closing the loop between theory and practice, ensuring the delivery of zero carbon new buildings is more readily and widely achievable.

Currently project teams are concluding their investigations and collating their findings, and dissemination of the results of the programme will begin in earnest in the first half of 2015.  However, as the programme has progressed, there are some consistent themes that are emerging.  Focussing on the non-domestic projects, I will address a couple of these emerging themes.

The first is around adopting innovative building systems to deliver low energy consumption and comfortable conditions, and unintended consequences associated with these technologies.  This covers a broad spectrum of building technologies including solar thermal, heat pumps, biomass boilers, earth tubes, rainwater harvesting, controls and natural ventilation strategies.  Innovation in its essence will have some inherent teething problems, which is often overlooked in the charge towards reaching our carbon reduction targets.  The obvious default stance is to specify proven and reliable technologies which are delivered by a team that is familiar with the technology, but our journey towards delivering true low carbon building in operation would inevitably be prolonged.

An additional level of complexity can be added with innovative systems; one healthcare facility introduced solar thermal and a combined heat and power (chp) unit, to supplement natural gas fired boilers for heating and hot water requirements. With several sources of heat complexity is added to the control strategy, trying to strike a balance between changing heat demands of the building and optimisation of the system.  This complexity, coupled with a requirement for increased operator understanding often leads to system underperformance.

The practicalities, maintenance and associated costs of innovative systems is seldom fully realised by clients.  An office reported success of the rainwater harvesting system, but were surprised at the frequency of filter changes to mitigate the system being blocked.  Another office had to regulate a fan associated with earth tube ventilation system, as running at a higher speed caused too much noise for occupants.  A school had ingress of water to an underground wood chip store rendering the biomass boiler idle for significant periods.  A hotel employed automatic external blinds which retracted in windy conditions to avoid damage, thus offering no shade to occupants during sunny, windy days.

It is clear a reality checking process is required for design decisions to mitigate such matters.  BSRIA’s Pitstopping guide, which resides within the Soft Landings framework describes a process that allows construction teams to periodically reconsider critical design issues by focusing on the perspective of the end user.  This also provides an opportunity for the client to understand the full ramifications of implementing innovative building systems for a more informed decision, and to align client expectations.

The second theme involves the process in delivering innovative technologies, with a particular a focus on commissioning and handover.  The commissioning period residing at the end of the build process is often susceptible to being squeezed.  When the decision has been taken to adopt an innovative building system, there is increased pressure during commissioning to ensure the system is operating as intended.  With the additional complexity associated with innovative technologies, it is vital the commissioning time is adequate to complete comprehensive scenario based testing; how is hot water delivered if the solar thermal does not provide a contribution, how is the building operator alerted the status of the system, how can the operator diagnose the problem, how long can the system operate without the solar thermal contribution without major detrimental effects etc.  To ease the burden on the commissioning period, it is clear commissioning should not be afterthought, but an integral part of the build process.

The commissioning period also signals a time where many of the stakeholders with tacit knowledge of the innovative building systems have changing responsibilities. It is vital this knowledge is captured for users before the opportunity is lost.  Building manuals, user guides and logbooks need to be completed so users can relate to their building environment, understand control of the environment and capture major alterations.

Many projects reported that guidance for both users and operators was often lacking, with several BPE teams developing guidance as part of their projects to support users.  Commonly BPE teams have also struggled to find initial design intent and operational strategy associated with innovative technologies, highlighting the importance of handover documentation.  Training of users is another key element to knowledge continuity, but several projects reported changes in staff being a core reason for innovative systems underperforming, as documentation was not kept up to date.  The value of clear concise user guidance is evident; BSRIA’s Building Manual and Building User Guides helps individuals responsible for creating building logbook and user guides.

In this blog, I’ve only addressed a couple of areas in regards to emerging themes, to hear more about findings from the programme, come hear me speak at the Energy Management Exhibition (EMEX), at Excel, London on the 20^th November, 2014.  Additionally, join the BPE community at connect.innovateuk.org, and search for Building Performance Evaluation.