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Learning from Our Buildings: A State-of-the-Practice Summary of Post-Occupancy Evaluation (2001)

Chapter: 6 The Role of Technology for Building Performance Assessments

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Suggested Citation:"6 The Role of Technology for Building Performance Assessments." National Research Council. 2001. Learning from Our Buildings: A State-of-the-Practice Summary of Post-Occupancy Evaluation. Washington, DC: The National Academies Press. doi: 10.17226/10288.
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Suggested Citation:"6 The Role of Technology for Building Performance Assessments." National Research Council. 2001. Learning from Our Buildings: A State-of-the-Practice Summary of Post-Occupancy Evaluation. Washington, DC: The National Academies Press. doi: 10.17226/10288.
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Page 55
Suggested Citation:"6 The Role of Technology for Building Performance Assessments." National Research Council. 2001. Learning from Our Buildings: A State-of-the-Practice Summary of Post-Occupancy Evaluation. Washington, DC: The National Academies Press. doi: 10.17226/10288.
×
Page 56
Suggested Citation:"6 The Role of Technology for Building Performance Assessments." National Research Council. 2001. Learning from Our Buildings: A State-of-the-Practice Summary of Post-Occupancy Evaluation. Washington, DC: The National Academies Press. doi: 10.17226/10288.
×
Page 57
Suggested Citation:"6 The Role of Technology for Building Performance Assessments." National Research Council. 2001. Learning from Our Buildings: A State-of-the-Practice Summary of Post-Occupancy Evaluation. Washington, DC: The National Academies Press. doi: 10.17226/10288.
×
Page 58
Suggested Citation:"6 The Role of Technology for Building Performance Assessments." National Research Council. 2001. Learning from Our Buildings: A State-of-the-Practice Summary of Post-Occupancy Evaluation. Washington, DC: The National Academies Press. doi: 10.17226/10288.
×
Page 59
Suggested Citation:"6 The Role of Technology for Building Performance Assessments." National Research Council. 2001. Learning from Our Buildings: A State-of-the-Practice Summary of Post-Occupancy Evaluation. Washington, DC: The National Academies Press. doi: 10.17226/10288.
×
Page 60
Suggested Citation:"6 The Role of Technology for Building Performance Assessments." National Research Council. 2001. Learning from Our Buildings: A State-of-the-Practice Summary of Post-Occupancy Evaluation. Washington, DC: The National Academies Press. doi: 10.17226/10288.
×
Page 61
Suggested Citation:"6 The Role of Technology for Building Performance Assessments." National Research Council. 2001. Learning from Our Buildings: A State-of-the-Practice Summary of Post-Occupancy Evaluation. Washington, DC: The National Academies Press. doi: 10.17226/10288.
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Page 62

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6 The Role of Technology for Building Performance Assessments Audrey Kaplan, Workplace Diagnostics Ltd. To date, building performance assessments have assessment process can be an effective tool for con- been limited, for the most part, to large organizations tinually improving the value of each facility, regard- and institutions. The substantial investment of time and less of its size or unique occupancy. money needed to mount such assessments using tradi- tional methods is a major hurdle for most midsize and INTRODUCTION small organizations or for niche groups. Relative to the number of facilities and organizations that could Cybersurveys complement existing survey methods benefit from such assessments, too few are done to of assessment, such as paper, mail, phone, in-person make them an effective tool for aligning occupant or interview, site visits, expert observations, photography, stakeholder expectations with the finished product. and instrument measurements. Advances in electronic communications and easy-to- Instruments to assess buildings continue to improve use Web browsers now make it attractive to conduct steadily. Prompted by the energy crisis of the 1970s, these assessments via the Internet or an intranet. instruments were developed to measure and/or diag- “Cybersurveys” or “e-surveys” (polls or assessments nose the effectiveness of building systems (e.g., walls; administered electronically) represent the breakthrough windows; roofs; heating, ventilation, and air condition- in social science research that will make this work ing; lighting). Generic methodologies were conceived cheaper and more effective to complete. Moreover, the to diagnose total building systems, and tools were innovative medium will likely inspire the invention of designed to assess the performance of specific building wholly new work and objectives that could not be done aspects. See, for example, A Generic Methodology for using existing assessment methods (Bainbridge, 1999). Thermographic Diagnosis of Building Enclosures (Mill Regardless of the medium, all assessment work and Kaplan, 1982) for a methodology and tools to begins with good research design, clearly stated objec- determine heat loss and uncontrolled air flow across tives, solid planning, and preparation to conduct a sur- building enclosures. The objective of methodologies vey, complete the analysis, and produce reports. This and tools developed at that time was to better under- chapter addresses issues related to implementing stand the cause of deficiencies—be they rooted in cybersurveys and assumes that sound principles of design or construction—and then to prescribe correc- building performance assessment are in place. Infor- tive actions and processes to prevent future occur- mation technology has unique features to gather feed- rences. back about building performance, which in turn can be In the 1980s, the heightened concern for the quality used to improve facility management and acquisition. of interior environments drove the development of new As the set of Internet users begins to reflect the popu- tools to better represent the total environmental setting lation in general, or a specific group under study, that occupants experience. Many traditional lab instru- cybersurveys may become the predominant method of ments were modified (or put on carts) and brought into administering building assessments. If widely used, the occupied buildings. The focus was to record environ- 54

THE ROLE OF TECHNOLOGY FOR BUILDING PERFORMANCE ASSESSMENTS 55 mental factors that influence human comfort and per- cybersurveys offer new and significant opportunities formance (e.g., light, sound, temperature, relative in the way building assessments are conceived and humidity, air quality, spatial configuration, aesthetics). completed. The author sees cybersurveys as the next These instruments were often cumbersome or too deli- technology-based advance in building performance cate for such robust applications, so manufacturers and assessments. The remainder of this chapter discusses researchers alike redesigned them to better match the how this technology is used to assess building perfor- field conditions and the nature of the data being col- mance. lected (see, for example, Schiller et al., 1988, 1989). Some of the features modified to make reliable field CYBERSURVEYS instruments included narrowing the instruments’ range, adjusting the sample duration and frequency, placing The unique features of computer technology (e.g., sensors to record levels in occupied zones (as opposed Web, e-mail, electronic communications) improve to air supply ducts, etc.), and immediate statistical upon and add efficiency to the polling process. The analysis of select field data for preliminary interpreta- traditional methods of surveying people—telephone, tion to guide the balance of the data collection. Since mail, or in person—are expensive and tend to be used then, there have been steady, incremental improve- now only by large organizations. The negligible cost to ments to the set of field instruments, benefiting from distribute surveys over the Internet or intranet and the miniaturization and faster processing as the whole com- potential to reach far and wide are changing the survey puter industry developed. industry. Now, small and medium-size businesses use Academic centers continue to advance the use of cybersurveys as a means to gather valuable informa- instruments to assess building performance. See, for tion from customers, potential customers, employees, example, the Center for Environmental Design or the general public. Readily available survey devel- Research (also known as the Center for the Built Envi- opment products help the nonspecialist to build a Web ronment) at the University of California, Berkeley, survey questionnaire, publish it on the Web, collect the www.cbe.berkeley.edu, and Cornell University, Ithaca, data, and then analyze and report the results (see New York, ergo.human.cornell.edu. Dependent upon Appendix E). These tools address how to conduct the funding to support building performance programs, research and the mechanics of data collection. They do these and other institutes lend instruments and materials not, and cannot, replace the management decision to to architecture, engineering, and facility management conduct the inquiry, how to interpret the numbers, or schools. These lending programs are intended to how to get actionable results from the effort. encourage the next generation of built environment Cybersurveys are distributed as e-mail to a specific professionals to build and manage environmentally address (either embedded in the message or as an responsible and energy-efficient structures. For attachment) or openly on the Web. There are more con- example, the Vital Signs program at the University of trol and layout options with Web-based surveys than California, Berkeley (1996), assembled tools to mea- with e-mail. With HTML (hypertext markup language), sure a range of building performance attributes. These attractive and inviting forms can be created. Some of were packaged into kits that educators could borrow the survey software packages have automated routines for their classes. Support funding has since expired, to design the survey’s physical appearance. however other programs carry on toward the same The cost of initial data collection is high—whether objectives. See, for example, the occupant survey for personnel to conduct interviews and code data or project <www.cbe.berkeley.edu/cedr/cbe>. for setting up a computer-based survey to automati- Improvements continue in the measurement of the cally solicit and compile data. However, the biggest physical built environment, but there are no major issues currently facing cybersurveys are the low breakthroughs or fundamental changes in how or what response rate (compared to traditional methods and is measured. Similarly, important advances in opinion relative to the potential based on number of visits to a research, such as telephone interviews, did not funda- site) and ensuring a proper sample. These issues are mentally change the way data were collected and ana- discussed in the next two sections, followed by lessons lyzed or questionnaires were designed (Taylor, 2000). learned from Web-based surveys. However, the visual and responsive characteristics of

56 LEARNING FROM OUR BUILDINGS RESPONSE RATE ended questions are richer, longer, and more revealing than those from other methods (Taylor, 2000). Cyber- It is widely agreed that the more attempts made to surveys are nontangible. Paper surveys may sit on contact respondents, the greater are the chances of their someone’s desk and serve to remind him or her to returning a survey. Similarly, a greater number of complete them. Individuals intending to complete a response formats increases the likelihood of more cybersurvey may bookmark the survey’s URL (uni- responses. Multiple contacts offering alternate ways of form resource locator) for later use but then forget to responding with appropriate personalization, singly and retrieve it. in combination, increase response rate. For example, Schaefer and Dillman (1998) reported from published studies the average response rate for e-mail surveys. SAMPLING With a single contact, the response rate was 28.5 per- The Web is worldwide. People anywhere on the cent, with two contacts it was 41 percent, and with three planet can answer a survey posted on the Web even if or more contacts the response rate was 57 percent. they are not part of the intended audience (unless con- Cybersurveys offer another contact vehicle and method trols are used, such as a unique URL, a password, or of response (e.g., interactive display, print and return) setting the meta tags so that the page is not picked up to the options already available. In and of itself, use of by search engines). To date, cybersurveys are com- this vehicle contributes to higher response rates. pleted by accidental volunteers (they stumbled upon A consistent finding is that cybersurveys are returned the survey) and self-selected individuals who choose more quickly than mail responses. In comparing sev- to participate. eral studies that used both e-surveys and paper (mail Because there is no central registry of Web users, and fax), response speeds ranged from 5 to 10 days for one does not know who is on-line, so one cannot electronic distribution versus 10-15 days for mail reliably reach a target population (see Appendix E for (Sheehan and McMillan, 1999). details of who is on-line and where they are geographi- To date, response rates from e-surveys have been cally). Moreover, there is no control on how electronic lower than for postal mail. E-mail rates range from 6 to messages are cascaded or linked to other sites. A mes- 75 percent. However the electronic and mail surveys sage can be directed to select individuals or groups used for this comparison (Sheehan and McMillan, who, for their own reasons, send it along to others. This 1999) had small sample sizes (less than 200) and varied behavior makes it difficult to ensure that the survey widely in survey topic and participants’ characteristics, reaches a random or representative sample of respon- so the spread is not surprising. E-surveys often achieve dents. Despite these sampling difficulties, careful use a 20 percent response, which is half of the rate usually of nonprobability sampling can produce results that obtained by mail or phone surveys. Some e-surveys represent a specific subset of the population (Babbie, have had less than 1 percent return of the possible 1990). responses, based on the number of hits to a Web site (Basi, 1999). There were some exceptions to this trend in the early 1990s when e-surveys were distributed to LESSONS LEARNED workers in electronic-related businesses (e.g., tele- The following recommendations for Web surveys phone and high-tech sectors). At that time, there was are adapted from published papers, Web sites, and the still a high-tech allure and/or novelty to receiving author’s experience (Bradley, 1999; Kaye and Johnson, e-mail, so response rates were acceptable (greater than 1999; Sheehan and McMillan, 1999; Perseus, 2000). 60 percent). This highlights how quickly the field is Recommendations are organized under the topics of changing. Lessons learned from early cybersurveys Web survey design considerations, sampling, publicity, may not necessarily apply in a current context. See and data collection and responses. Appendix E for a discussion of the changing context of on-line communications. Other reasons for low participation in on-line sur- Web Survey Design Considerations veys may involve a reluctance to share one’s views in a 1. Keep the survey as short as possible for quick nontraditional environment. However, for those who completion and minimum scrolling. are comfortable with this arrangement, replies to open-

THE ROLE OF TECHNOLOGY FOR BUILDING PERFORMANCE ASSESSMENTS 57 TABLE 6-1 Internet Users, by Region, Who Prefer Sampling to Use the Web in English Rather than Their Native 1. To generalize the results to a wider population, Tongue. define samples as subsets of Web users based on Region % Who Prefer English some specific characteristic. 2. Solicit responses from the target population. This North America 74 can be done by linking the survey from select Africa, Middle East 72 sites, by posting announcements on discussion- Eastern Europe 67 type sites that the target population is likely to Asia 62 Western Europe 51 use, or by selecting e-mail addresses posted on Latin America 48 key Usenet newsgroups, listserves, and chat forums. Invited participants should be given an Source: USA Today (2001). identification number and password, that are both required to access the Web-based survey. 3. Clearly state the intended audience in the intro- duction to the survey so, hopefully, only those to whom it applies will respond. 2. Use simple designs with only necessary graphics to save on download time. Publicity 3. Use drop-down boxes to save space, reduce 1. Systematically publicize the survey daily through clutter, and avoid repeating responses. various means. Create awareness of the survey at 4. State instructions clearly. a wide variety of Internet or intranet outlets to 5. Give a cutoff date for responses. reduce bias. “Pop-up” surveys may attract more 6. Personalize the survey (e.g., use recipient’s e-mail responses than simple banner invitations that are address in a pre-notification letter; identify the fixed to a page. Advertising on select sites might survey’s sponsor, which can also add credibility). increase the number of completions but does not 7. Assure respondents that their privacy will be pro- continually invite (spam) a few discussion groups tected—both their e-mail address and the safety while ignoring others. See Table 6-2 for methods of their computer system (virus free). to invite people to a survey. 8. Conduct pre-tests to measure time and ease for 2. Pre-notify respondents who would find the survey completing the survey. Electronic pre-testing is relevant (e.g., those to whom an important issue easier and cheaper than traditional methods. is current or timely). 9. Try to complete the survey using different browsers 3. Do not go overboard on publicity, just announce to uncover browser-based design flaws. the survey. 10. English-language cyber-surveys can easily over- 4. List the survey with as many of the major search come geographic barriers (Swoboda et al., 1997). engines as possible. Services, such as “Submit It,” See Table 6-1 for the percentage of Internet users send listings to many search engines with just one who prefer to use the Web in English rather than entry. Then use different search strategies and terms their native language. to locate the survey and uncover glitches or errors. TABLE 6-2 Methods to Attract Respondents to a Cybersurvey. Announcements Browsing intercept software Customer records E-mail directories Harvested addresses Hypertext links Interest group members Invitations (banners, letters, etc.) Pop-up surveys Printed directories Registration forms Snowballing Staff records Subscribers Web site directories Source: Bradley (1999).

58 LEARNING FROM OUR BUILDINGS 5. Check that the survey links remain posted and that methods, and presentations for building performance the URL is visible on the page. assessments. For example, new lines of research might 6. Write the complete URL in announcements or be conceived that integrate occupants’ perception of messages because it can be an easy, “clickable” interior environments with data from the building con- link in some e-mail transmissions. trol system and/or weather conditions or that track the 7. Ask respondents how they found out about the use of facilities as recorded by smart cards and/or the survey to gauge which sites and discussion out- spatial coordinates of workspaces as recorded by lets were most effective in reaching the target computer-aided drafting systems. audience. Select opinion leaders and/or professionals could be 8. If appropriate and/or feasible, offer incentives for drawn to an Internet-based “brain trust” that focuses on completing the survey (ranging from the survey special questions related to the built environment. The results to lottery tickets, money, or discounts for Internet or intranet and Web are excellent media for a third-party product). Check the laws governing establishing virtual libraries and databases that many incentives because these vary by jurisdiction. can access and use. Establishing sites with existing data allows other researchers to produce interpretations, conclusions, or knowledge that is in some way differ- Data Collection and Responses ent from that produced in the original inquiry (i.e., sec- 1. Design the survey so that it is submitted with a ondary analysis). This work would economically and simple click of the mouse or keystroke. efficiently add to the experience and knowledge of 2. Upon receiving the survey, set up for an auto- building performance assessments. matic thank-you reply to the sender saying that With cybersurveys, questions can be asked of any- the survey was successfully transmitted. one, worldwide, who is on-line. It is feasible to poll a 3. To check for duplicate responses, ask for respon- wide population about issues that impact a specific dents’ e-mail address and/or track senders’ Internet building. The sample is not limited to those who work or intranet protocol address. in, visit, or are somehow involved with a building. Tap- 4. For ease of importing e-mailed data into a statis- ping into these opinions becomes important when there tical software program, design the return forms is a highly visible construction, a new and important so that each question is listed on one line followed public structure, or a controversy connected with a by its response and a corresponding numerical facility. Public opinion might provide valuable insight value. to how a building, its occupants, or a particular issue is 5. People may respond to electronically viewed viewed. For example, an incidence of sick-building scales differently than to scales that are spoken or syndrome or an environmental disaster might be officially on paper. Taylor (2000) observed that fewer resolved to those managing a facility, but the local com- people picked the extremes on e-scales than when munity could remain suspicious and unsupportive of they heard the questions and response options. the organization. Using wide-reaching cybersurveys to tap into that sentiment gives insight that might influ- ence decisions regarding the building’s publicity, image, CONCLUSIONS AND DISCUSSION operational management, and the communication to The Internet or intranet and World Wide Web enable users and other interested parties of what was done. traditional building performance assessments to be There is great value in being able to reach a popula- accomplished more cheaply and effectively. The elec- tion that is not yet at a facility. For example, high school tronic medium may well become the primary survey students are actively on-line and, through cybersurveys, vehicle owing to its convenience, low-cost of distribu- can be asked their expectations for their university tion and return, ability to verify (check for errors) and experience—how they will live, learn, study, and make receive data—including rich text replies—in electronic friends. It would be insightful to determine that they format, and the fact that it is an easy way to give have, for example, no desire to study in traditional respondents feedback. All this is done incredibly fast libraries or in their dormitory rooms. They may expect with an attractive, visual presentation. “cybercafés,” collaborative work settings, or learning The opportunities presented by the medium itself environments that ease their transition into work envi- will likely lead to the invention of new products, ronments where they will earn a livelihood. Through

THE ROLE OF TECHNOLOGY FOR BUILDING PERFORMANCE ASSESSMENTS 59 select demographic questions, survey researchers can research activities range from the evaluation of com- characterize the future university population and sug- fort and environmental quality in offices, to the assess- gest built environment features compatible with their ment of total building performance, to the design of expectations. Universities may use these as features to workstations with personal environmental controls. In attract top students and then to elicit the best work from addition to consulting, Ms. Kaplan is a regular speaker enrolled students. at professional conferences and continuing education Much of the young, skilled work force in the tech- seminars, and is a certified instructor for professional nology sector comes from outside North America and training courses with the International Facility Man- from different cultures. Each has its own expectation agement Association (IFMA). She was an adjunct pro- of work and the workplace. Here again, using cyber- fessor at the University of Manitoba and served on surveys to understand their expectations of the work- IFMA’s international board as a director from 1998- place and to educate them about North American work- 2000, as chair of IFMA’s Canadian Foundation; and as places can speed their integration into the work force. a trustee of IFMA’s foundation. Ms. Kaplan received There is a strong business case to support this use of IFMA’s 1996 Distinguished Author Award for her co- cybersurveys since they readily translate into business authored book Total Workplace Performance: Rethink- objectives of worker productivity and reduced time to ing the Office Environment. She holds a bachelor of market for products. architecture from Carleton University and a master of Occupant feedback is difficult to get, or unreliable, science in architecture from Carnegie Mellon when people are stressed, such as when they need hos- University. pitals, senior residences, and funeral parlors. However, after the crisis has passed and their emotions are stable, REFERENCES they could offer insight to aspects of the physical set- ting that helped them at the time or that would have Babbie, E. (1990). Survey Research Methods. Belmont, California: Wadsworth. been of benefit. Cybersurveys can reach these people Bainbridge, W. (1999). Cyberspace: Sociology’s natural domain. Contem- at a time when they can offer measured opinions on the porary Sociology 28(6):664-667. built environment. Basi, R. (1999). WWW response rates to socio-demographic items. Journal of the Market Research Society 41(4):397-401. The rewards of cybersurveys are so rich that their Bradley, N. (1999). Sampling for Internet surveys: An examination of potential will surely be used and the methodological respondent selection for Internet research. Journal of the Market and sampling issues of today will be resolved. It is hard Research Society 41(4):387-395. to imagine future building performance assessments Center for Environmental Design Research (known as the Center for the Built Environment) (1996). Vital Signs. Berkeley: University of Cali- without extensive use of the Internet or intranet and the fornia (www.cbe.berkeley.edu). Web. However, traditional methods will continue to be Kaye, B., and Johnson, T. (1999). Research methodology: Taming the cyber used, perhaps becoming a smaller part of the overall frontier. Social Science Computer Review 17(3):323-337. Mill, P., and Kaplan, A. (1982). A Generic Methodology for Thermographic work. Printing did not fully replace handwriting, radio Diagnosis of Building Enclosures. Public Works Canada. Report Series did not take the place of newspapers, and television did No. 30. not supplant movies or radio. Cybersurveys enable Perseus. (2000). Survey 101—A complete guide to a successful survey many things that could not be done or afforded using (www.perseus_101b.htm). Pike, P. (2001). Technology rant: I’m tired of feeling incompetent! PikeNet traditional methods. The addition of this medium to the February 11 (www.pikenet.com). tools for building performance assessment greatly Schaefer, D., and Dillman, D. (1998). Development of a standard e-mail enhances the accessibility and value of such data and methodology. Public Opinion Quarterly 62:378-397. Schiller, G., et al. (1988). Thermal Environments and Comfort in Office of the evaluation process itself. Buildings. Berkeley: Center for Environmental Design Research, CEDR-02-89 Schiller, G., et al. (1989). Thermal comfort in office buildings. ASHRAE ABOUT THE AUTHOR Journal October 26-32. Sheehan, K., and McMillan, S. (1999). Response variation in e-mail sur- Audrey Kaplan is president of Workplace Diagnos- veys: An exploration. Journal of Advertising Research 39(4):45-54. tics, Ltd., an Ottawa-based consulting company that Swoboda, W., Muhlberger, N., Weitkunat, R., and Schneeweib, S. (1997). specializes in the evaluation and design of workspace. Internet surveys by direct mailing. Social Science Computer Review 15(3):242-255. Ms. Kaplan has been actively involved in building per- Taylor, H. 2000. Does Internet research work? International Journal of formance as a research scientist and consultant for 20 Market Research 42(1):51-63. years and has published widely in the field. Her USA Today (2001). Searching the Web in native language. February 27, p. 7B.

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In 1986, the FFC requested that the NRC appoint a committee to examine the field and propose ways by which the POE process could be improved to better serve public and private sector organizations. The resulting report, Post-Occupancy Evaluation Practices in the Building Process: Opportunities for Improvement, proposed a broader view of POEs-from being simply the end phase of a building project to being an integral part of the entire building process. The authoring committee recommended a series of actions related to policy, procedures, and innovative technologies and techniques to achieve that broader view.

In 2000, the FFC funded a second study to look at the state of the practice of POEs and lessons-learned programs among federal agencies and in private, public, and academic organizations both here and abroad. The sponsor agencies specifically wanted to determine whether and how information gathered during POE processes could be used to help inform decisions made in the programming, budgeting, design, construction, and operation phases of facility acquisition in a useful and timely way. To complete this study, the FFC commissioned a set of papers by recognized experts in this field, conducted a survey of selected federal agencies with POE programs, and held a forum at the National Academy of Sciences on March 13, 2001, to address these issues. This report is the result of those efforts.

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