The weakest link?

The drive for ‘smart’ buildings automated controls risks leaving the humans who use the buildings in the dark and wasting electricity through inappropriate, inefficient or poorly-calibrated automated systems.

Time and again, post-occupancy evaluation across a range of settings suggests that occupants want more, not less control over their environment, with lighting frequently coming top of the list - Post Occupancy Evaluation of School Refurbishment Projects: Multiple Case Study in the UK .?

This result is repeated in feedback from over 2,600 workers in state-funded buildings in Minnesota, who found the same central themes of inadequate control of electric lighting, automatic lighting systems that didn’t meet task-specific needs and poor integration between daylighting and electric lighting leading to excessive contrast that contributed to eye strain and migraine -?The Impact of Design Interventions on Occupant Satisfaction: A Workplace Pre-and Post-Occupancy Evaluation Analysis .?

Inviting us all to engage with the lighting can reduce energy use by up to 50% -?Improving lighting energy efficiency through user response .

Simply switching to?a manual-on option instead of the standard ‘occupancy on/vacancy off control can cut the electricity bill by up to 62% -?A preliminary study of occupants’ use of manual lighting controls in private offices: A case study .

The solution??

Ask the people who use the building what they want!

But most design decisions are made months, if not years, before the space is occupied and tenants will change over time.?

So regular measurement and verification is key not only to improving environmental performance but boosting tenant satisfaction too.??

This is where smart buildings really can come into their own, with the potential to track key performance indicators that integrate the needs of people and the environment at the whole building, system and even at the equipment level as this paper explains -?System-level key performance indicators for building performance evaluation .?

A survey of occupants in a large American Headquarters before and after a retrofit intervention and found that, out of all the 12 indoor environmental quality categories, lighting was the dimension that received the most attention, specifically ease of control, effectiveness of automatic systems, adjustability and quality of task lighting. It also found that users considered that being able to adjust the lighting for visual comfort, and the quality of task lighting boosted their perception of how productive and healthy they were -?Post-occupancy Evaluation Study of the Impact of Daylighting and Electric Lighting in the Workplace .?

So what’s in the gap??

The lighting sector traditionally functions on a ‘box-shifting’ business model, where warranties and after-sales service are the first casualties of ‘value engineering’. This is compounded by the difficulty in fault finding limiting liability in a complex integrated system: where does the luminaire end and the power supply, controls and human factors begin??

This review by the International Energy Agency Energy in Buildings and Communities Programme reviews barriers to change and makes a passionate case for a paradigm shift:? Building professionals need to transition from a perception that occupants are an inconvenience - 'sources of indoor heat gains and contaminants who are content with standardized indoor environmental conditions’ to recognising the complex and dynamic bi-directional interaction between occupants and buildings -?Introducing IEA EBC annex 79: Key challenges and opportunities in the field of occupant-centric building design and operation .?

Whatever the complexities, post-occupancy evaluation is likely to become the norm over the coming years, in London at least. Not simply to maintain WELL certification, but to comply with the new BSI standard 40101-Performance of occupied and operational buildings -?Building performance evaluation of occupied and operational buildings (using data gathered from tests, measurements, observation and user experience). Specification ,?and the London Plan Policy SI 2 -?The London Plan 2021 - Table of Contents ?that requires major developments to monitor energy usage over 5 years in use.

Perhaps it's time to get smart about smart technology so we can take care of people and planet too.