Along with the proliferation of green buildings comes the question: “How do building professionals measure the success of a green building?” Of course, rating systems (such as LEED) measure how green the building is, but Platinum, Gold, and Silver don’t reveal how the building performs on a daily basis. Andrew Shapiro, founder and CEO at New York City-based GreenOrder, a business strategy and marketing firm that helps companies align environmental and energy leadership with business objectives, points to quantitative research that shows greater worker productivity, less absenteeism, higher job satisfaction, and even higher sales in retail locations as benefits to occupants of green buildings. But, what do the occupants - those who work in the building - have to say about daylighting, thermal comfort, and energy efficiency? Do they see the results of working in a green building? Collecting their input is critical to meeting the goals of green building.
Post-occupancy evaluations (POEs) have been used for more than 40 years to help architects and building owners determine the performance and success of their buildings. Recently, this process has begun to be applied to the growing market of green buildings. “Developers and building owners should be thinking about the benefits of green building, including the satisfaction of tenants and employees ... I think occupant surveys could be useful to really understand the degree to which the owners or leasers of green office space are feeling that they’re getting the benefit out of [green buildings],” Shapiro says. However, formally collecting occupant feedback regarding workspace conditions is not yet commonly undertaken in green buildings due to the challenges of creating an unbiased survey, compelling enough occupants to take the survey to make it viable, and sorting through the results to take measurable and appropriate action. Recently, however, a few organizations have taken steps to encourage and facilitate the collection of occupant feedback regarding green buildings.
The Center for the Built Environment (CBE) at the University of California, Berkeley, has created a survey that measures occupant perception of indoor environmental quality (IEQ), gauging satisfaction levels and self-reported productivity. This Web-based survey allows building owners and managers to collect information on a building’s performance for benchmarking purposes. Any negative data can then be analyzed to make adjustments to the building as well as to future projects.
With 215 surveyed office buildings, 21 of which have earned a LEED rating or been designated as green by their owners, the CBE’s IEQ survey provides a satisfaction comparison between occupants of green buildings vs. occupants of non-green buildings. According to a 2006 paper released by the CBE, “Occupant Satisfaction with Indoor Environmental Quality in Green Buildings,” those surveyed in sustainable office buildings were most pleased with thermal comfort, air quality, office furnishings, and cleaning and maintenance. However, the paper does qualify that these results may be influenced by the newness of the green buildings surveyed. When the CBE compared the 21 green buildings to non-green office facilities built within the last 15 years, there was no statistical difference between the two groups.
Dissatisfaction among occupants of green office buildings in the CBE database is most often due to lighting and acoustical problems. Although acoustical complaints were slightly higher from occupants of green buildings, both groups that were surveyed had the same concerns with open-office elements (concerns included remarks such as “people talking in my neighboring areas” and “people overhearing my private conversations”). “Not enough daylight” and “reflections [on] the computer screen” were the two most-frequent complaints about lighting in green buildings. Once again, non-green-building occupants had the same complaints nearly as frequently. In the case of the 21 surveyed green buildings, CBE researchers found that individuals had less influence over lighting controls than users of non-green buildings.
To encourage occupant feedback, LEED-NC Version 2.2 includes an opportunity to gain points for occupant feedback in the area of thermal comfort (which was added in October 2005). EQ Credit 7.2 awards 1 point for “agree[ing] to implement a thermal-comfort survey of building occupants within a period of 6 to 18 months after occupancy.” The credit also mandates that, if more than 20 percent of occupants are not satisfied with the building’s thermal comfort, building professionals must develop a plan of action for correcting the problem.
Architects were once the primary beneficiaries of POEs, but surveys like the CBE’s are geared toward building managers and owners, helping them improve occupants’ workspace experience and build their own portfolios - especially in the sustainable market. Shapiro says, “It pays to do research, even if the research is just talking to existing tenants to understand what they care about ... Ultimately, any green strategy will benefit from a consumer-focused perspective.”
Anne K. Goedken ([email protected]) is new products editor at Buildings magazine.