According to a survey by the Ministry of Health, Labor and Welfare, the number of mood disorders tends to increase year by year in Japan. Under such a background, from December 2015, it is obliged for employers to perform stress checks of workers once a year. In such a stress society, improvement of office environment is an urgent issue. As is well known, some foliage plants have effects of humidity control and VOC removal from indoor air, improvement of productivity and reducing workers' mental stress as well.
 In the past, a number of previous studies on indoor plants focusing on these effects have been seen, and most of them were implemented in simulated office spaces in the past. However, recently Iwasaki et al. and Matsumoto et al. have installed some plants in actual office spaces and the psychological effects of plants on office workers are beginning to be considered.
 The objective of this study is to examine the effect of indoor plants on physiological/psychological responses and productivity, and to demonstrate the mental healthcare for office workers. In order to clarify the effect of indoor plants, we conducted a demonstration experiment in an office. This experiment aims to clarify the effects of indoor plants arranged in workplaces on workers' mental health, such as physiological responses, psychological responses and productivity.
 The experiment was performed in two rooms (Office A, Office B) in an office on the eighth floor of a building located in Kyoto, Japan. Office A was a call center and Office B was a general office. Subjects were office workers working in one of the above two rooms. Twenty-two healthy people in Office A and 19 healthy people in Office B participated in the experiment. Participants were required to measure physiological responses and answer a Web questionnaire after work once or twice a week. Each office worker worked as usual during the experiment period.
 The experiment was performed from the end of March 2016 to the beginning of September 2016. In the experiment, nine cycles (one cycle is two weeks) were conducted while changing the type of plants. Plants were arranged in the same amount as possible with a green cover ratio of 10 %. A preliminary experiment without plants was conducted as a reference case. Survey items are divided into four items: indoor environment (temperature, humidity, CO₂ concentration, illuminance, sound level), physiological responses (salivary amylase activity, critical flicker fusion frequency (CFF)), psychological responses (a questionnaire survey through the Web based on SAP and a questionnaire survey “Jikaku-sho shirabe” by which evaluated work-related fatigue feelings and fatigue symptom intensity), and productivity (simple task, calls per hour (CPH)).
 Indoor environment indices of this study ranged wider than those of the laboratory experiment. The result of evaluating the thermal comfort of each office using PMV showed that Office A was slightly warm, while Office B was neutral. The relaxation effects of plants on visual fatigue were found to be significant in CFF for female when arranging the plants with some petals. Mean score of fatigue symptom intensity showed that foliage plants have a significant effect to reduce the feelings of drowsiness. Effect of the improvement of the productivity using plants installation could not be confirmed in terms of simple task and CPH. Our results suggested that plants installation in office space has some mental healthcare effects, although this study had some limitations because of the demonstration experiment. Some experimental problems related with plants preparation restriction, plants order, a variation of some indoor environment indices, LED lamp lightings are to be solved in the future.

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 Building vibrations induced by external sources, such as road traffic or railway, can degrade the habitability, in particular, small-scale buildings, such as detached houses in Japan, because of their smaller mass and less from sources, compared to large buildings, such as apartment or office. Several studies have shown that the amplification of buildings is greater in the horizontal direction than in the vertical direction. The resonance frequency of building vibration mode with dominant horizontal vibration can be close to the resonance frequency of large vehicles caused by their suspensions. Although the vibration at the ground is at a magnitude below human perception threshold, a vibration problem could be caused by the vibration amplification due to resonance of the building. For this reason, when designing a building at a site with ground vibration at a concerned magnitude, it is necessary to design it for the performance against environmental vibration.
 In this study, the ultimate goal is to develop evaluation methods for the habitability to building vibration by external vibration sources, such as road traffic and railway, based on subjective response to vibration, such as magnitude, discomfort and the like. The applicability of the current domestic and foreign evaluation methods of environmental vibration was investigated by evaluating subjective responses to horizontal vibrations measured in a laboratory experiment involving human subjects. The evaluation methods developed in the recent studies with vertical vibrations were examined also. Vibrations produced by actual vibration sources, such as road traffic, railway, construction work, and sinusoidal vibrations were used as input in the experiment.
 The relationship between domestic and foreign evaluation methods of environmental vibration and subjective responses appeared to be most reasonable with Vibration Dose Value which considered the duration of vibration by the fourth power. It was found that the evaluation “L_Vmax + 20 log₁₀(T^1/4)” was reasonable evaluation method where “L_Vmax” is the maximum value of vibration level with the time constant of 630 ms and “T” is the duration of vibration level over 57 dB.

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 It is vitally important to estimate the visibility of all visual targets in real environments in order to maintain a visual safety especially for low-vision people. As luminance images of real lit environments are relatively easily obtained, it is reasonable to attempt to establish a method to estimate visibility of objects using luminance images.
 Authors have proposed C-A graph based on contrast profile method. In contrast profile method, luminance contrast is obtained by convolution of 9 by 9 matrix called n-filter into a logarithmic luminance image. This n-filter is a kind of the Mexican hat filter. A luminance contrast profile of the object is obtained by changing detection size of the filter. A logarithmic average of the object and the immediate background is obtained by the same size averaging filter as the n-filter in the logarithmic image of luminance. C-A graph presents luminance contrast and logarithmic average as vertical and horizontal axes for varying object sizes respectively. It expresses the three factors necessary for visibility estimation. By the author's past experiment using Landolt ring, that estimation of visibility using C-A graph is possible has been confirmed.
 In this study, visibility evaluation experiments using circular objects as visual target was conducted as a fundamental study to develop estimation visibility for low-vision people. Circular objects with varying luminance contrast, background luminance and object size, were displayed on 27 inch digital display screen. Subjects observed circular targets displayed on uniform-luminance background with both eyes from 625 or 2500 mm distance. Subjects answered whether the circular target was visible or invisible. 10 subjects with median visual acuity 1.35 and 10 subjects with median visual acuity 1.70 participated in experiments.
 Experimental results analyzed using contrast profile method and presented on C-A graph. By plotting visible and invisible contrast values for each target size and finding out contrast values that half of the subjects evaluated as visible, visibility threshold curve can be drawn between visible and invisible conditions on C-A graph for each circular object size. As object size became smaller, visibility threshold curve opened outward on C-A graph and both positive and negative visibility threshold contrast becomes greater. A visual threshold estimation model was established from threshold curves obtained for each object size. For difference of visual acuity of subjects, the variable obtained by multiplying object size and the visual acuity was used to concatenate the results. In this study, visibility threshold estimation model of circular objects adoptable to wider range of object size using C-A graph was established. The consistency between the established model and Blackwell's study was confirmed.
 Whether these models are applicable to people with other visual ability, such as low-vision and average but weak vision, must further be examined.

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 Heat loss tends to occur at building entrances by invasion of outdoor air and leakage of indoor air because the entrance is opened by people's passage. So reducing the inflow / outflow of airflow at building entrance is important in consideration of the thermal environment and energy saving of the building and energy-saving. Air curtain is one of the methods for reducing the external air load at building entrance. Since the air curtain shut-off between inside and outside by blowing out wind, it is susceptible to temperature and pressure differences. Final goal is performing an evaluation of the energy saving when air curtain is installed to real building. This paper is a basic study for the goal considered the change of parameters around the outlet and the aperture with temperature difference and pressure difference by model experiments and CFD analysis.
 In model experiments, experiments using shrinking models are performed under isothermal condition. And we created a CFD model that reproduces experimental equipment, comparing experiments and CFD analysis results, consistency of both methods was confirmed.
 In case study with CFD analysis, we conducted steady state analysis and unsteady state analysis. Steady state analysis considered the influence of the change of the size of the outlet and the opening on the shut-off performance with isothermal condition was clarified using experiment model and the influence of temperature difference on shut-off performance of AC using retrofit simple model. Unsteady state analysis considered the influence of human passing using experiment model and the influence of using automatic door and air curtain together using retrofit simple model.
 Steady state analysis with isothermal condition by experiment model has 6 study case, blowing speed, opening height, opening width, outlet width, outlet length, blowing angle. Among these, it became clear that the influence of blowing speed and outlet width factors on shut-off performance is particularly large. Steady state analysis with non-isothermal condition by retrofit simple model has 2 study case, summer and winter. It became clear that the influence of the temperature difference on the outside air invasion amount is small and the heat shut-off rate is equal to the airflow shut-off rate with pressure difference. Finally, in steady state analysis, it became clear that the performance of shut-off of air curtain can be approximated to one formula.
 Human passing analysis has 3 study cases, number of moving people, moving speed, pressure difference. In number of moving people study, there was a tendency that the quantity of outdoor invasion increased as the number of moving people was increased and differences in quantity of outdoor invasion were also seen by moving form differences. In moving speed study, there was a tendency that the quantity of outdoor invasion increased as the moving speed was accelerated. In pressure difference study, there was a tendency that the quantity of outdoor invasion decreased as the pressure difference was increased. Throughout, the influence of the human passing on the performance of shut-off of the air curtain is small with pressure difference.
 Air curtain using with automatic door analysis has 2 study case, single door and double door. When calculating the airflow shut-off rate when air curtain is installed single and double door, each performance of shut-off is almost equal to that if the air curtain is installed in the simple opening.

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 The effect of air pressure on moisture transfer inside porous building materials cannot be ignored in cases where air cannot escape through the surfaces of the materials; in such cases, air is compressed by the movement of the moisture. Such a situation can be brought about by the sealing or surface-protecting materials that prevent water from penetrating into a surface, which is often seen in a typical water absorption test. However, in the field of architectural engineering, the effect of air pressure under wetting processes has not been sufficiently examined, and the validity of calculation models for the transfer of both air and moisture inside materials has not yet been verified. Therefore, this study investigates the behavior of water under the influence of air-pressure changes and develops a proper calculation model for it.
 First, we conducted two types of water absorption tests on bricks. In both of the tests, water infiltrated the specimens through their top surfaces, and the time profiles of the water content were measured using a gamma-ray attenuation method. While only the side surfaces of the specimen were impermeable to moisture and air in Case 1, the side and bottom surfaces were impermeable in Case 2. In Case 2, we expected the air pressure inside the specimen to increase, as the air inside it would not be able to escape through the bottom; this would result in the infiltration of the water being prevented. The results for Case 2 show that the moisture resistance of the specimen was seemingly greater than those obtained in Case 1. We also discovered that the amount of water that was absorbed during Case 2 was not significantly different from the amount absorbed during Case 1. Because air bubbles were observed to have escaped through the water on the top surface in Case 2, we determined that the air pressure inside the specimen returned to atmospheric pressure over time. Therefore, we expected the steady states of Cases 1 and 2 to be similar. It should be noted that the measured water content in Case 2 varied depending on the horizontal position of the measurements.
 Second, we developed a calculation model corresponding to the experiment that was based on the equation for the transfer of both air and liquid water. The calculation results show that the increase in the water content slowed significantly when the changes in the air pressure inside a material were considered. In addition, the calculated and measured water contents agreed well with one another and allowed us to verify the validity of our model. The analysis also showed that when air escapes from the material, the amount that escapes should be adequately considered by the calculation model. According to the results of both the experiments and the simulation, the infiltration process under the influence of the air pressure was as follows: At an early stage in the infiltration process, because the air pressure inside the material was not much higher than atmospheric pressure, water infiltration was not prevented significantly. However, this caused a rapid compression of the air inside the specimen, which resulted in high air pressure within it. This trend reduced the rate of the increase of the air pressure because further water infiltration was reduced by the high pressure. During the final stage of the infiltration, the air pressure began to decrease to atmospheric pressure and water content reached almost the same values as those in Case 1.

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 The frequencies and characteristics of heatstroke occurred in secondary/high schools were investigated by using the data of NAASH (National Agency for the Advancement of Sports and Health), and analysis was dune for a period of 10 years from 2005 to 2014. The investigated cities were Sapporo City, Sendai City, Tokyo City, Nagoya City, Osaka City, Hiroshima City, Fukuoka City, Kumamoto City and Kagoshima City in Japan. The environmental factors, e.g., outdoor temperature, relative humidity and global solar radiation, were obtained from the closest meteorological observatories from the respective cities at the time of occurrence.
 During the 10-year period, out of 915,447 cases of accidents and injuries, 3,819 cases of heatstroke were reported in the data of NAASH for the investigated secondary/high schools of the cities. Of the 3,819 cases, 2,204 occurred at school grounds, e.g., schoolyard, gymnasium, pool and school building. Of the 2,204 cases occurred at school grounds, 1,430 occurred in the schoolyard, 557 in the gymnasium, 145 in the school building, and 26 were in the swimming pool. Out of 2,204 cases of heatstroke at school, 1,538 cases occurred during athletic club activities, 309 occurred on field day, 142 occurred during the physical education class.
 The relationships between the environmental factors, i.e., outdoor temperature and WBGT (wet-bulb globe temperature) and the risk factor, i.e., the frequencies of heatstroke accidents and the odds ratio of heatstroke, were obtained. The risk factors of heatstroke for schoolyard, gymnasium, and school building, had a good correlation with WBGT, and this relationship would be used for the evidence when designing safe school environment. It showed that the odds ratio of heatstroke for schoolyard at 31 °C of WBGT was 7.09 based on the standard WBGT of 22 °C. On the other hand, the odds ratio for gymnasium at 31 °C of WBGT turned out to be 4.92 and that for school building 3.67. The rather high risk level for gymnasium and school house could be interpreted to mean the importance of indoor climatic control for avoiding heatstroke in schools.
 As it can be seen in the number of heatstroke occurred during each class schedule, the frequencies of heatstroke during the athletic club activities were appreciably high for schoolyard and in gymnasium. It was confirmed that the frequencies of heatstroke of male students occurred on schoolyard was almost three times higher than those of female students. On the other hand, the frequencies of female students in gymnasium were somewhat greater than those of male students. These finding may indicate that the athletic club activities which mostly female students participate have a significant influence on the frequencies of heatstroke occurred in gymnasium.
 The accidents of heatstroke on schoolyard during athletic club activities, physical education, and field day occurred most frequently at the grade of 31 °C WBGT. The frequencies of heatstroke occurred in gymnasium during athletic club activities passed its peak at the grade of 31 °C WBGT as well. The quasi-peak of frequencies in gymnasium during cultural club activities and cultural festival is, however, distributed in a wide range of WBGT.
 The results of the frequencies of heatstroke during each sports club activities showed that the number of heatstroke occurred on schoolyard during baseball, basketball, and soccer was quite frequent. If the number of accident during each club activity is divided by the population of the concerned club, the determined accident ratio in gymnasium during female badminton club was the considerably the highest. Although badminton is played in gymnasium, the risk level during badminton under hot and humid condition would be equal to that of baseball or rugby on schoolyard.

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 The globalization of people and things results in the short average distance of the networks and emerging infectious disease can spread immediately after the development in this world. Thus, preventive infection control measures are important. The infection risk should be evaluated to adopt effective infection control measures. In this study, the cough machine that can generate human-like cough to evaluate the infection risk in indoor environments were developed to evaluate infection risk. The cough expired volume, travel distance, velocity, total mass of droplets, and particle size distribution of the droplets of the cough machine were compared with the subject experimental data. The deposition of droplet on facial mucous membranes, such like eyes and a mouth, at various distances and horizontal surfaces at different heights were measured using the cough machine and thermal manikin. It was shown that the number of droplet deposited on the position of facial mucous membranes decrease drastically over 90 cm when the infected person and susceptible person faced each other. On horizontal surfaces, the droplet deposited most at 50-60 cm and more than 90% of the droplet deposited within 90 cm. The number of droplet deposited on the surface under 50%RH condition was larger than that under 30%RH condition. The effect of relative humidity was larger on the near surface because the propagation time is shorter than it takes to deposit on the distant far-surface. We provide experimental evidence to evaluate droplet and contact infection risk that enable to address a question of the relative importance of each infection route.

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 This research aims to verify the effectiveness of the structure of a “visualization system” and energy saving measures with regard to existing facilities of an industrial university, according to energy type, load and room application, based on the analysis of data acquired over several years. The results are as follows:
 1) We constructed a versatile “visualization system” with the potential to be introduced and executed over a short period without halting the functions (practices) of existing facilities that lack energy management systems such as BEMS, using general purpose environment management tools, wireless sensors and existing campus LAN.
 2) The installment and management conditions of apparatus in each room of the university facilities, which are difficult for the facility manager to keep track of, were clarified by means of a survey, and the lighting load power consumption and items for the energy saving measures were clarified according to each room application.
 3) The effects of reductions in energy consumption since the introduction of the “visualization system,” and the factors for such reductions are as shown below.
 ·Compared to the average energy consumption before the introduction of the system, that of the primary energy conversion of the four years after the system was introduced showed an annual reduction in energy consumption of approximately 10%.
 ·The primary energy consumption per unit area in FY 2012 was 867 MJ/(m²/year), which demonstrates the effectiveness of the system and the series of energy saving activities.
 ·The factors for the reductions in energy consumption were the reductions in electrical power consumption, of which 80% was lighting load and 20% was motive power load.
 ·The reduction in lighting load – a result of operational improvements – in the common/administrative areas (including lecture rooms) was remarkable. In the staffroom/seminar rooms, load reductions trends could be observed in approximately half of the rooms, meaning there is room for improvement with regard to management and operation.
 ·With regard to the amount of fuel consumption, fluctuations occurred according to the outdoor temperature and operational control conditions, meaning that definite reduction trends could not be observed. However, the correlation between the difference in indoor and outdoor temperatures and the amount of fuel consumed verifies that appropriate heat source operation control is carried out in response to load throughout the entire campus facilities. It also shows that, from the correlation between the outdoor temperature and fuel consumption, it is possible to predict the amount of fuel consumption and evaluate the suitability of situations regarding heat source operation.
 4) After 4 years of operation, the level of familiarity with the “visualization” system has increased, but there is a decreasing trend in the number of accesses. In order to realize further contributions to energy conservation, it is thought that reconfiguration to include features such as an interactive function for sending and receiving information from the end user is necessary.

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 In the summer of 2012, Kansai region was facing an electricity deficit due to the stoppage of nuclear power plants after the Great East Japan Earthquake. As one of the electricity saving measures for residential customers, an incentive program called “Electricity Saving Trial” was demonstrated in Kansai region. An article reported that the electricity saving effect of the participants was 8%, while the effect in the whole residential sector was 5%. It is important to clarify how the electricity saving is achieved during the incentive program, in order to certainly obtain the expected effects. This issue can be clarified if abundant data of electricity consumption for individual end-use would be available. However, it is difficult to collect sufficient numbers of data to analyze the electricity saving effects at a large scale such as Kansai region.
 Therefore, this paper proposes a method that disaggregates whole-house electricity consumption data measured by smart meters, which are becoming widespread, into end-uses. The smart meter data used in this study is the hourly average electricity consumption of more than 1,000 households in Kansai region. The proposed method enables us to disaggregate the data into four end-uses: base use, active use, heating use, and cooling use. The cooling and heating use is separated from other consumption by analyzing the sensitivity of electricity consumption to outdoor air temperature.
 One of the advantages of the proposed method is consideration of the secular change of the boundary temperatures of starting/finishing to use cooling/heating. Another advantage is consideration of the differences in temperature sensitivity of electricity consumption between former period and latter period of the summer/winter. Moreover, the method can compare the electricity usage among years because the impact of the weather condition on the electricity consumption can be removed by inputting a common outdoor air temperature to the regression model.
 Additionally, the proposed method is applied to disaggregate the smart meter data in Kansai region and we analyze the electricity saving effect during the incentive program. The knowledge gained from this analysis is the following.
 1) Except FY2013, the boundary temperature of the start of cooling use is lower than that of the end of cooling use. This result implies that occupants used cooling more frequently in the latter period than the former period of the summer, even if the outdoor air temperature is relatively low. However, the boundary temperature of the start of cooling use rise after FY2012 comparing with FY2011. It demonstrates that occupants stop to use cooling earlier in FY2012 and FY2013 than in FY2011 (Table 3).
 2) The total base use reduces by approximately 6% in FY2012 comparing with the previous year. It suggests that the reduction includes the electricity saving effects not caused by occupant activity, such as cutting standby power of appliances.
 3) In the daytime of the summer, the operating hours of cooling in FY2012 and FY2013 decrease by approximately 11% from FY2011. It indicates that the action to save electricity of shortening the operating hours of cooling is relatively easy to continue. However, the reduction ratio in the especially hot hours is 16% in FY2012 and it falls to be 9% in FY2013. These results suggest that the action to save electricity especially in hot hours, such as rising set point temperature, is difficult to continue for even the participant households (Fig. 15).

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 Due to the power shortage caused by the Great East Japan Earthquake that occurred on March 11, 2011, Tokyo Electric Power Company and Tohoku Electric Power Company gave notice of planned power outages. The government took the actions of supervising, reducing power consumption, setting a numerical target for each electric company, and directing consumers to curb their consumption. For these reasons, the with the growing power-saving consciousness, even general households were expected to increase momentum for the introduction of power-saving measures and use energy-saving equipment. Although previous studies have revealed the actual conditions of energy consumption, power-saving consciousness and energy saving measures in nonresidential buildings. There have been few studies on the actual conditions of energy consumption of residential houses before and after the earthquake disaster. Therefore, in this study, we conducted a questionnaire survey via post-mail in the prefectures of Nagano, Yamanashi and Niigata, and revealed the transition of energy consumption, the actual conditions of power saving and the reduction of electricity consumption, respectively. Furthermore, we compared Yamanashi and Niigata, where the electric company had notified planned power outages. With Nagano, where there no planned outages.
 The questionnaire was consisted of five sections: questions on energy consumption, power-saving consciousness, energy-saving equipment, power-saving measures in summer and also in winter.
 The number of valid responses was 193. Of these, 65% was from Nagano Prefecture, 46% from Yamanashi Prefecture, and 6% from Niigata Prefecture.
 The findings obtained from the analysis of the questionnaires are shown below.
 1) Energy consumption greatly decreased after the earthquake disaster in 2011.
 2) Taking into consideration the power consumption reduction rate, changes in temperature showed a reduction of power consumption in the three prefectures. Although the reduction rate was high only in winter in Nagano, it was high in both summer and winter in Yamanashi and Niigata.
 3) In power-saving conditions, the results showed that the more households were actively involved in power-saving, the larger the reduction of power consumption.
 4) In regard to energy-saving equipment, compared to Nagano Prefecture, the tendency to install highly efficient equipment in Yamanashi Prefecture and Niigata Prefecture was much greater.
 5) The results revealed that despite the active introduction of energy saving/peak suppression equipment in Niigata, where air conditioners save power or not is not a concern. On the contrary, the introduction rate of energy saving/peak suppression equipment was lower in Nagano and Yamanashi, but of the rate of taking action to save energy was high. We considered one of the reasons to be that many people in Niigata have been using energy saving/peak suppression equipment, and consequently, they believe that their actions will lead to saving energy. Also, it is relevant to highly humid weather in Niigata: therefore, they need to use air conditioner for long stretches of time. In the future, it would be necessary to continue to conduct a survey on the energy consumption changes and power-saving consciousness.

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 Recently, insulation retrofits of existing houses have been considered an effective measure to prevent global warming. In Japan, many houses are not thermally insulated properly, and a space heater is usually used only in the living room. Therefore, in northern Japan, especially in the Tohoku region, temperatures in rooms without space heating are very low during the winter, and the temperature differences between the heated living room and other rooms of the house without space heating are very large. It can be expected that existing houses retrofitted with thermal insulation will be thermally comfortable and consume less energy. Three types of thermal insulation retrofits were examined in the present study, with each type differing according to the areas insulated: overall insulation retrofit with all rooms insulated (Houses E, W, M, and O), partial special insulation retrofit with several rooms insulated (House S), and partial insulation retrofit of part of the building envelopes (House K). The overall reduction in environmental load by each type of insulation retrofit has not yet been clarified. Therefore, the goals of this study were to obtain basic data concerning the thermal insulation retrofits and to promote the energy saving of existing houses based on the methods and effects of energy saving for retrofitted houses.
 The authors investigated the environmental performance of six detached wooden houses in the Tohoku region before and after thermal insulation retrofit. In this paper, the performance of insulation and air tightness, indoor thermal environments, and annual energy consumption before and after the retrofit were analyzed. The effects of thermal insulation retrofits were clarified from this case study. This paper firstly describes the results of the heat loss coefficient (U_A) and the equivalent air leakage area in proportion to the floor area (C) in each house before and after the retrofit. Secondly, the indoor thermal environment during the heating season and annual primary and secondary energy consumption before and after the retrofit in six thermally renovated houses are evaluated.
 The U_A for the building skin of each house was calculated before and after the retrofit from the design documents of each house. The UA of Houses E, W, M, and O in which all rooms were thermally renovated met the energy saving standard. During the heating season, temperature differences between the living room and other rooms were smaller after the insulation retrofit with all rooms renovated, and the vertical temperature differences in the living room were lower than 3.0 °C after the insulation retrofit with the living room renovated. On the other hand, for House S in which only some rooms were thermally renovated, the temperature differences between the renovated and non-renovated rooms were large during the heating season. To prevent cold exposure in rooms, it is important to decrease the temperature difference between heated and unheated rooms. A bathroom and washroom in particular should be included in thermally renovated spaces. Thermal insulation is very effective for decreasing the energy consumption for space heating. However, several renovated houses consumed more energy for space heating than before the thermal insulation retrofit because of the increase in the total square area being heated and heating time. Notably, annual energy consumption in most houses decreased annually, indicating that occupants' awareness of energy saving had improved after the thermal insulation retrofit.

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