With regard to fire safety for exterior walls of a building, fire-resistance performance is considered according to the current building standard law of Japan. However, fire safety performance is not specifically regulated from the viewpoint of reaction-to-fire performance, such as fire propagation caused by combustible materials or products which are installed on the exterior side of fire-resistant load-bearing walls. From such a background, JIS A 1310 “test method for fire propagation over building façades” was established at 2015, which was considered as the test method for evaluating fire propagation over exterior walls. However, there was some argument that heat output of burner (600 kW prescribed in JIS A 1310 as minimum) was not sufficient to evaluate fire propagation over exterior walls. Therefore, in this research, in order to select suitable heat output for JIS A 1310 which can evaluate the occurrence and extent of fire propagation on combustible exterior façade clearly compared with incombustible façade, authors examined the relations between heat output and ejected flame size and height and the relation between heat output and fire propagation behavior over combustible façade.
 First, using incombustible facade, authors tested with changing heat output of burner in 4 levels, namely 300, 600, 1000, 1200 kW, for clarifying the ejected flame’s property on JIS A 1310. Assuming heat release rate of ejected flame from the opening (Q_ex) as the value subtracted critical heat release rate of external flame (Q_vcrit) from measured heat release rate (Q), the relationship between Q_ex^* and Q was organized. It indicated that ejected flame with less than 830kW at JIS A 1310 would form relatively weak ejected flame over exterior walls and would be not enough to evaluate fire propagation over exterior walls. Moreover, in order to decide whether to evaluate fire propagation by JIS A 1310, initial flame height (x_p) and initial flame growth (δ_F) were calculated by assuming that flame existed in the case with façade surface temperature exceeding 500°C. It indicated that initial flame growth (δ_F) could over the test specimen's top with more than 1010kW, and would be too strong to evaluate fire propagation over exterior walls by JIS A 1310.
 Second, changing heat output of burner in 3 levels, experiments according to JIS A 1310 were conducted with combustible façades, namely external thermal insulation cladding system (ETICS), wooden façade and aluminum composite panel. Heat release rate of these were estimated 600, 1000 and 1200kW, but measured heat release rate of those were 581, 883 and 1107kW respectively. As a result of JIS A 1310 test with ETICS, it was difficult to observe fire propagation by JIS A 1310 tests with 1107kW heat output of the burner. Compared with actual fire issues, fire propagation over aluminum composite panel with 581kW seems to be small. On the other hand, fire propagation over aluminum composite panel with 883kW seem to be similar to actual fire issues.
 In conclusion, it was revealed that setting heat output of burner from 830 to 1010 kW was better in terms of ejected flame size and possibility for evaluating fire propagation over building façades. From the test results with 883kW burner, of which ETICS, wooden façade and aluminum composite panel are targeted, it was also revealed that JIS A 1310 test could (1) grasp fire propagation behavior occurred in actual fire issues, and (2) evaluate exterior façade fire propagation within the test specimen size.

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 Japan has set the goals to implement ZEBs ( net zero energy buildings ) in newly constructed public and private buildings by 2030. In order to implement ZEB, thorough energy savings is also desired in the lighting field, and effective daylight harvesting is considered important in addition to adopting lighting control with highly efficient lighting equipment and various sensors.
 In addition, daylight use has recently attracted attention to improve the health and comfort of people working in buildings.
 Although it is possible to reduce the amount of electric power usage used for luminaires by daylight harvesting, bringing daylight into interiors may increase solar heat gain at the same time, so it is necessary to comprehensively evaluate energy performance including thermal environment. In recent years, environmental simulation with data from BIM shape which is a three-dimensional design drawing of buildings are becoming possible. By using BIM, it is possible to incorporate the shape of a curved facade and the shape of the complicated outside sun shading into a simulation, and to evaluate energy performance. Also, as the demand for environmentally conscious buildings has increased, comprehensive evaluation of solar heat gain and natural lighting for facades equipped with various outside sun shading is desired.
 In this study, the lighting power usage was worked out by annual calculation of the light environment by using simulation program Radiance with BIM. In addition, the results of Radiance were combined with the thermal load calculation program NewHASP, and the annual thermal load was obtained. We also developed a simulation model that accurately evaluates electricity usage annually by introducing thermal load calculation results into energy calculation program LCEM.
 Using this model, we comprehensively evaluated light and heat in daylight harvesting systems. Regarding the heat load, although it has the effect of outside sun shading, it turned out that there is no effect of outside sun shading in Tokyo for lighting and air conditioning electric power usage.
 In the future, the calculation of complex outside sun shading such as curved surfaces should be conducted, and we would like to optimize the motion/rotation of outside sun shading.

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This paper focuses on the airtight performance of reinforced concrete (RC) walls used as exterior walls in a typical residential building (prototype building) in Japan. Air leakage tests were performed using two full scale RC wall specimens subjected to shear damage. The airtight performance of RC walls was evaluated using a fan pressurization method for air leakage. Furthermore, this paper evaluates a limit corresponding to function maintenance of the prototype building based on a design limit of the C value and the air leakage test results.

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 Introduction
 Labeling system of building material corresponding to formaldehyde emission rate started in 2003 in Japan. Basically, formaldehyde emission rate from building materials should be measured by small chamber method based on JIS A 1901, in the meantime, desiccator method, i.e. head space method, has been widely used as an alternative. Recently, market supply of glass desiccator specified by JIS R 3503 was canceled and there is no prospect of future production, so there is a need for an alternative to existing desiccators. Hence, it is necessary to investigate the various alternative desiccators on the market specified by ISO or DIN and to clarify performance related formaldehyde emission test.
 This paper reports the results of three-dimensional digital modeling for four types of alternative desiccators on market and conducts the numerical analysis of diffusion phenomenon in their desiccators. Since the geometric shape in the desiccators for each product and the relative distance from the surface of test building materials to the water surface as an adsorbent were also different, equivalent diffusion length scale, ‘L_d’, corresponding to hypothetical one-dimensional diffusion distance for each desiccator were numerically analyzed.
 Methods
 Three-dimensional laser scanner was used to create the three-dimensional digital models of inner geometries for five types of desiccator on market. The detail geometries of test specimen as formaldehyde emission material were also reproduced in desiccators. Numerical analysis for formaldehyde emission, diffusion, and sorption inside desiccators were carried out for targeting five types of desiccator geometries.
 Results
 As a result, the equivalent diffusion length scale ‘L_d’ of the four desiccators, i.e., the alternative four desiccators (model A, B, C, and D), differs by about 25% compared to the current desiccator model R.
 Conclusions
 Because of the geometry discrepancies between desiccators depending on the type and the differences of vertical distance from water surface (adsorbent) to the test specimens, each type of desiccator have different ‘L_d’, the equivalent diffusion length scale corresponding to one dimensional diffusion length from the others. Therefore, it is necessary to calibrate experimental result using L_d. The time constant τ_e defined by equation (6) was almost proportional to the relative magnitude relation of the diffusion time scale τ_D of equation (5). The time constant τ_e of each desiccator was around 20 to 120 seconds and the diffusion time scale τ_D was about 0.6 to 1 hours.

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 With progress in information technology, the controllability of the building facility system continues to improve. Especially, unlike the heat source air-conditioning equipment, the lighting equipment has little time lag, so fine control over time and space is possible. Recently, it has become technically possible to allocate an IP address to each lighting fixture and independently control all the lighting fixtures. To evaluate the value of such advanced control, it is necessary to check whether the control works effectively for human activity in the building. However, if it is impossible to judge whether good or bad is necessary without measuring the real building, it is inconvenient to design the control. Therefore, using a simulation, we aimed to predict the energy-saving effect of the lighting control due to the absence of workers in the office.
 We divided the office space into meshes and constructed an agent model of the office worker moving between meshes using the A^* algorithm. By using several office worker models, we calculated the time the worker is in each office's mesh. We controlled the lighting fixtures in this virtual office room based on human sensors. We quantitatively evaluated the influence of such conditions as the occupancy rate, waiting time, fade-out time, and minimum output rate on the energy consumption rate of lighting fixtures. The energy consumption rate was roughly consistent with the survey results in past research. An approximation formula was developed to predict energy consumption rate, and the procedure for predicting the energy-saving effect of human sensor control is described.

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 Recent years have seen the wide adoption of floor insulated houses. Floor insulated houses is Many studies in the past have reported the high humidity of crawl spaces in the summer season. In this research, we propose a humidity control method for crawl spaces in floor insulated houses based on actual measurement data. The effects of that proposal on crawl spaces were clarified through experimentation and simulation. The result is shown as follows.
 1) In the actual measurement, crawl space of target house is average relative humidity 80% or more in summer season. It was guessed that high humidity of crawl spaces can be suppressed by supplying indoor air to crawl space.
 2) In the experimentation, it was confirmed that the relative humidity decreased due to the air supply effect. But the cumulative percentage at a relative humidity of over 80% didn't fall below 80 percent. Therefore, this result shows that the risk of fungal contamination is high.
 3) In the simulation, calculations were performed to supply indoor air to the crawl space as in the actual measurement. it was confirmed that the relative humidity decreased due to the air supply effect in all areas. And it was shown that the risk of fungal contamination is relatively low where the cumulative percentage of relative humidity of 80% or more is 50% or less. Increase rate of heating load in the house was about 10% at maximum.
 As above, characteristics of hygrothermal behavior in the crawl space were clarify. And it was shown that supplying indoor air to the crawl space is effective for reduction of high humidity in the crawl space. The proposed method is effective only when indoor air is low humidity by air conditioner etc. But it is guessed that there are many people who use air conditioning in summer season. Therefore, it is believed that the method proposed in this research is important.

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 Since Japan has a very aged society and the proportion of elderly people is increasing, falling down accidents of elderly people are increasing year by year. Since falling down accidents cause bedridden, it is one of the causes threatening the daily lives of elderly people. Therefore, early detection at the time of falling down is a big problem in Japan.

 In this research, we developed an algorithm which can detect falling down of the elderly accurately, with the aim of watching the elderly. For detection of falling down, a triaxial accelerometer which is often used for wearable devices was used. In creating the algorithm, we analyzed physical information (such as age, weight and height) and waveform of acceleration when falling down. In addition, we proposed to define the threshold of the maximum combined acceleration when falling down. The research procedure is shown below.

 First of all, we investigated the acceleration of young people and the elderly in their daily lives. As a result, it was found that the maximum combined acceleration is different between young people and elderly people.
 Next, the falling test was conducted by 5 subjects aged between 20 and 70 years old, and acceleration data at the time of falling down, 72 times was obtained. Next, based on this experiment, an algorithm for detecting falling down was created. The algorithm was constructed based on the following four acceleration characteristics:
 (1) The maximum combined acceleration when falling down is 3.5 G or more.
 (2) The posture just before falling down is standing.
 (3) The angle of the body before falling down and after falling down is 70 degrees or more.
 (4) After falling down, the condition of falling down continues for more than 2 seconds.
 When all of the above four points are satisfied, it is judged to be “falling down”.
 Next, the accuracy of the created algorithm was verified. The accuracy verification checked whether or not it was judged to be a fall when actually falling down and whether or not it was judged to be a fall though it was not falling down.
 As a result, using the created algorithm, it was possible to detect 70 falls over 72 falling down data. Moreover, in the verification of false detection related to a fall in everyday life, only 2 out of 17 days were mistakenly detected as falling down.
 From the above, it was confirmed that falls can be detected with high precision by the created algorithm.
 The fall detection algorithm created in this research is useful for early detection for the emergency situation of elderly people. Therefore, it is possible to secure the safety of the lives of elderly people and to prevent lonely death caused by falling down of elderly people living alone.

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 This paper investigates the effects of change in household structure on the residential energy consumption by end-use. Structural change, such as decreasing household size, is a factor for decreasing energy demand per household. On the other hand, energy consumption as a whole can be increased by losing scale economy. Moreover, as a new contribution of this paper, it was revealed that the impact of the change in household structure, compared to other end-use purposes, tends to be larger for energy consumption per household for hot water supply. The reason for this difference is that a large part of the energy consumption for hot water supply is unlikely to be shared among members of a household, so that it is likely to be affected by a change in household size. Also, single-person households tend to not fill bathtubs. In other words, energy consumption as a whole for hot water supply is hardly to be affected by change in household structure, so it is likely to be directly affected by the population change. Therefore, under the depopulation trend expected in the future, energy consumption for hot water supply is likely to decrease from the viewpoint of household structure. Meanwhile, energy consumption for space-heating per household is insensitive to change in household structure, so this energy consumption as a whole is likely to increase. This finding suggests that improving the thermal insulation performance of housing and the efficiency of appliances for space-heating is important for decarbonization in the residential sector. Although previously published studies have investigated the impact of household structure on energy consumption, this study acquired new findings by revealing that the effect can differ between end uses. Such analyses can be utilized to specify end uses having high priority for implementation of countermeasures.
 Moreover, in addition to population aging and change in household size, this study revealed that the decrease in the proportion of detached houses is also a factor for reducing energy consumption for space heating. As shown by this study, due to the increase of the proportion of collective houses, energy consumption during 2010–2015 decreased by 0.5% in the five-year period. Although previous studies have suggested an impact of the increase in collective housing on CO₂ emissions and electricity demand, this paper contributes to the literature by revealing the impact in an actual time from observed data. This suggests that compact development of cities leads to a decarbonizing of the residential sector by encouraging people in single-person households in suburban areas to move into collective housing.

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