Healthy Buildings 2017 Europe July 2-5, 2017, Lublin, Poland

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1 Healthy Buildings 2017 Europe July 2-5, 2017, Lublin, Poland Paper ID 0013 ISBN: Proposal of Environmental Assessment Index for Office Buildings Considering the Wellness of Workers Junta Fujisawa 1*, Sayana Tsushima 1, Anri Itoh 2, Shuhei Takahashi 1, Ryutaro Kubo 3, Shin-ichi Tanabe 1 1 Waseda University, Tokyo, Japan 2 MHS Planners, Architects & Engineers, Tokyo, Japan 3 Nikken Sekkei Research Institute, Tokyo, Japan * Corresponding fujisawa@tanabe.arch.waseda.ac.jp SUMMARY In this research, an environmental assessment index considering the wellness of workers is proposed by comparing the evaluation items of the WELL Building Standard and Comprehensive Assessment System for Built Environment Efficiency (CASBEE) the Japanese building environmental assessment index in order to investigate and improve the health performance of Japanese offices. Based on the results of the comparison, indoor environment, functionality, nourishment, and fitness were selected as the main evaluation items of the proposed index. Furthermore, to set the weighting of each evaluation item, a questionnaire on health awareness was conducted among office workers. Four office buildings were investigated using the proposed index, WELL Building Standard, and CASBEE. A comparison of the evaluation results for the proposed index and CASBEE indicates the possibility of evaluating healthy performance and sustainability through a combined use of the two indexes. KEYWORDS WELL Building Standard, CASBEE, Questionnaire 1 INTRODUCTION The deterioration of the indoor environment and long-term sedentary work are damaging to the health of workers. Therefore, it is important to introduce measures to assess the physical and mental health of workers in office buildings. In 2012, the WELL Building Standard, an environmental assessment index for health and wellness was developed in the USA. However, no environmental assessment index exists in Japan to assess the health and wellness of offices. Furthermore, it is difficult to adapt the WELL Building Standard for the evaluation of Japanese offices. The objective of this study is, therefore, to investigate the health performance of Japanese offices and the measures that can improve it. 2 MATERIALS/METHODS For this study, the following materials and methods were used: comparison of the WELL Building Standard and CASBEE; decision on the evaluation items of the proposed index;

2 setting the weighting of each evaluation item using a questionnaire; and evaluation of office buildings using the proposed index, the WELL Building Standard, and CASBEE. Comparison of the WELL Building Standard and CASBEE The correspondence between the WELL Building Standard and CASBEE was established in order to determine the evaluation items to be used to assess the wellness of Japanese workers. CASBEE is an evaluation system that comprehensively evaluates the lifecycle quality of Japanese buildings such as environmental consideration, indoor comfort, and landscape. The evaluation items of CASBEE are roughly classified into Quality (Q: environmental quality in architecture) and Load (L: environmental load in architecture) ; and the Built Environment Efficiency (BEE) assessment indicator is calculated by these scores. Figure 1 shows the relationship between the evaluation items of the two indexes. In the analysis of the WELL Building Standard, only Preconditions were used. A comparison of the two indexes confirmed that the indoor environment and functionality evaluation items were common. The evaluation items that occurred only in the CASBEE were tolerance, energy, and surrounding environment. The evaluation items that occurred only in the WELL Building Standard were nourishment, fitness, and water quality. Figure 1. The relationship between the evaluation items of the two indexes. Decision on the evaluation items Based on the above mentioned comparison, indoor environment, functionality, nourishment, and fitness were selected as the main evaluation items of the proposed index. The indoor environment item was evaluated on a scale of 1 to 5. The other items were evaluated as 1 when the criteria were not met, 3 when unknown, and 5 when the criteria were met. Keeping a high score in the proposed index meant a high subjective health of workers. Because the correlation between subjective health and actual health had been determined, it was estimated that the actual health of workers improved by keeping high score in the proposed index. A detailed description of the main evaluation items is given below. Indoor environment: all items belonging to Q1 indoor environment in the CASBEE were used for this main item because they matched the items in the WELL Building Standard. In particular, the items were regarding sound environment, thermal environment, light environment, and air quality. The weightings setting in the CASBEE platform were used. Functionality: items belonging to refresh space in the CASBEE matched the items belonging to adaptable spaces of mind in the WELL Building Standard. In particular, the items were regarding the presence of meeting spaces, refresh spaces, nap support equipment, and medical facilities.

3 Nourishment: although the items belonging to nourishment were not part of the CASBEE, they were considered important for wellness evaluation in the WELL Building Standard. In particular, the items were regarding vegetable intake, allergy labeling, food additive labeling, and nutritional information. Fitness: the items belonging to fitness were also considered important for wellness evaluation in the WELL Building Standard. In particular, the items were regarding the presence of signs that encourage the use of stairs, accessibility of stairs, and designs on corridors and stairs. Setting the weighting of each evaluation item To set the weighting of each evaluation item, a questionnaire on health awareness was conducted using office workers as participants. The questions were in connection with the importance of each middle classification, physical health, and mental health, as well as each main item for physical and mental health. A total of 407 questionnaires were distributed, and 283 copies were collected (70% recovery rate). Figure 2 shows the importance of each main item with reference to physical health and mental health. The question on the importance of each main item with reference to physical and mental health was answered according to the four-grade system: most unimportant, unimportant, important, and most important. As a result, it was confirmed that workers regarded indoor environment as most important and few workers regarded nourishment and fitness as important. A B Figure 2. Importance of each main item. A) With reference to physical health, B) With reference to mental health. Table 1 shows the proposed health assessment index. From the results of the questionnaire survey, the weighting of each evaluation item was set using the analytic hierarchy process (AHP). With respect to the weighting of each middle classification, the largest item was refresh space belonging to functionality (0.26), vegetable promotion belonging to nourishment (0.30), and exercise promotion belonging to fitness (0.36). The results determined that workers viewed items that directly affected work as important. Furthermore, the importance of nutrition management and exercise in offices are not major issues of concern for Japanese workers. Table 1. Proposed health assessment index. Evaluation items Weighting Details 1. Indoor environment 2. Functionality 2.1 Meeting space Scoring by CASBEE. 2.2 Refresh space 2.3 Nap support equipment 2.4 Medical facility There are meeting spaces that workers can use to share ideas or tasks. There are spaces for workers to refresh and intensive work. There are spaces for nap such as sofa. There are medical facilities.

4 Evaluation items 3. Nourishment 3.1 Vegetable promotion 3.2 Allergy labeling 3.3 Food additive labeling 3.4 Detailed nutritional information 4. Fitness 4.1 Stair accessibility 4.2 Stair promotion 4.3 Exercise promotion Weighting Details There are vegetables on offer (at least 5 varieties). Food and beverages sold or distributed within the premises are labeled to indicate that they contain at least 2 of the following allergens: peanut, fish, shellfish, soy, milk/dairy products, egg, wheat, and tree nuts. Food and beverages sold or distributed within the premises are labeled to indicate that they contain at least two substances of the following: artificial colors, flavors, and sweeteners. For food and beverages sold and distributed within the premises, at least two of the following are displayed: total calories, protein, fat, carbohydrate, total salt content, and total sugar content. There is signage to encourage the use stairs in the corridor and elevator hall. Stairs are located in easy-to-find areas at the entrance or elevator hall. Corridor or stairs are borrowed some artwork, music, daylight, or view. Evaluation of office buildings Table 2 shows the summary of the buildings that were evaluated. Four office buildings were evaluated by CASBEE, the WELL Building Standard, and the proposed index to determine their environmental friendliness features and wellness performance in the offices. The offices used were green buildings of less than 10 years after completion, and total floor area of more than 10,000 m 2. The evaluation method by the CASBEE was implemented using the CASBEE s prescript. Regarding the evaluation method by the WELL Building Standard and the proposed index, each evaluation item was evaluated as 1 when the criteria were not met, 3 when unknown, and 5 when the criteria were met. Table 2. Summary of the buildings used for the evaluation. Building A Building B Building C Building D Location Total floor area (m 2 ) Number of floors Tokyo Pref. ca. 120, above ground 4 below Completion year 2013 CASBEE certification S rank (New Construction) 3 RESULTS Kanagawa Pref. ca. 30,000 7 above ground 1 below 2009 A rank (Yokohama) Tokyo Pref. ca. 70, above ground 1 below 2011 A rank (New Construction) Kanagawa Pref. ca. 90, above ground 2 below 2012 S rank (Yokohama) Evaluation results for each item Figure 3 shows the evaluation results for each main item of CASBEE. The outside environment score was high in buildings A and C because of their landscape preservation features. The energy score was high in building A and D because of the availability of heat load control schemes and energy-efficient equipment. The off-site environment score was high in building A, C, and D because of the availability of global warming countermeasures and pollution abatement measures.

5 A B C D Figure 3. Evaluation results for each main item of the CASBEE. Figure 4 shows the evaluation results for each main item of the WELL Building Standard. Only preconditions were evaluated and the evaluation items with respect to the old building or material management under construction were not used. With respect to fitness item, facilitative aesthetics was satisfied in building A and D because of the availability of windows in the staircase. With respect to mind item, biophilia was satisfied in building A, C, and D because grasses were grown. A B C D Figure 4. Evaluation results for each main item of the WELL Building Standard. Figure 5 shows the evaluation results for each main item of the proposed index. The product of each middle classification and weighting gives the score for each main item, and the product of each main item and weighting gives the final score. The functionality score was high in building A because of the availability of refresh spaces and medical facilities. With respect to fitness item, building A and D satisfied exercise promotion while building A also satisfied stair promotion. Figure 5. Evaluation results for each main item of the proposed index. Evaluation results for each index Figure 6 shows the evaluation results for each index. With respect to the CASBEE, the scores of indoor environment and energy, which were set high weighting, were higher than the scores of the other items by considering the weighting. With respect to the WELL Building Standard, the final scores of all buildings were comparable. However, there were differences in the scores in fitness and mind items. With respect to the proposed index, there were

6 differences in the scores in functionality and fitness items. Moreover, the scores of nourishment and fitness items exhibited a trend that resulted in lower values than the score of functionality item when considering the weighting as the weightings of nourishment and fitness were lower than the weighting of functionality. A B C Figure 6. Evaluation results for each index. A) the CASBEE, B) the WELL Building Standard, and C) the Proposed index. 4 DISCUSSION Regarding the WELL Building Standard, the weighting was not set; however, the number of the middle classifications affected the final score. Therefore, satisfying a large number of the middle classifications of air was related to increasing the final score. With respect to the proposed index, the weighting of functionality was high; therefore, functionality was important for office workers and had the tendency to affect the wellness in offices. On the other hand, the weighting of fitness was low. This indicated that few workers tried to introduce daily exercise because of the difficulties encountered in the offices. As the scores of functionality and fitness of building A, which achieved a high final score, were high, satisfying these evaluation items led to health improvement. 5 CONCLUSIONS There were many middle classifications that we were unable to investigate whether these criteria were met in the evaluation of the WELL Building Standard. Hence, it was determined that some evaluation items should be modified for the evaluation of Japanese offices. The BEE of CASBEE was not consistent with the final score of the proposed index, which indicated that the CASBEE was not sufficient to evaluate the health performance. However, it might be possible to evaluate both building sustainability and health performance by simultaneously using the CASBEE and the proposed index. 6 ACKNOWLEDGEMENT The authors would like to acknowledge all the people who supported us by participating in the questionnaire. 7 REFERENCES International WELL Building Institute THE WELL BUILDING STANDARD VERSION 1.0 Japan Sustainable Building Consortium CASBEE-New Construction Evaluation Manual (2014). Murakami S. and Ikaga T Planning of housing and community for healthy life. Bulletin of Social Medicine, Vol.31 (1), 1-8.

7 Kinoshita E The Introduction of AHP in Japanese.