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［フォーラム後記｜Forum Epilogue］木造集合住宅の実現に向け、都市・建築における環境分野の国内動向と、木造集合住宅を先導する欧州の事例を踏まえた上で、行政、研究、供給側および一般ユーザーの視点を交えて議論しました。各領域のトップランナーと環境省省エネ住宅推進大使の壇蜜さんによるトークセッションでは、壇蜜さんの切れ味鋭いコメントや質問で会場が大きく沸きました。　木造集合住宅の普及が進む欧州では、高い環境性能を保持する手段として木造が選択されています。そして「木造」と言ってもすべて木材で建物をつくるのではなく、木材を適材適所に柔軟に活用することで、経済的障壁を超え、環境にやさしくかつ快適な木造集合住宅を数多く実現しています。　講師の皆様から、行政も研究者も積極的に木造を推進すべく法整備や補助制度を用意し、大規模木造建築の実現を後押ししていることと、また木材は環境だけではなく、健康にもよい影響を及ぼすことを解説いただきました。フォーラム終了後、ご来場の方から数多くの問い合わせをいただき、木造に対する関心の高さをあらためて感じています。　国土の約2/3を森林で覆われている日本で大中規模の集合住宅を建てる際、当然のように「木造」を選択肢に入れる時代はもう目の前まで来ていることを再認識する機会となりました。 ［ファシリテーター：渋谷 篤］With a view to the realization of multi-unit timber-framed housing, domestic environmental trends affecting the fields of urban planning and architecture, as well as pioneering European examples were looked at, followed by discussion from the viewpoints of government, academia, housing providers, and users. The audience became further animated thanks to the astute comments and probing questions to the experts by energy-saving homes ambassador Ms. Mitsu Dan. In Europe, where wood-frame multiunit housing is becoming widespread wood has been chosen as a means of maintaining high environmental performance. By employing methods that use wood selectively and flexibly̶the right material in the right place̶Europe is overcoming the economic hurdle of wood construction and is building many wood-frame multifamily housing structures that are gentle on the environment and comfortable for the users. The speakers explained that Japan’s government and researchers are actively promoting wood construction by developing laws and subsidies, and that wood is good not only for the environment, but also for human health. Many comments were received from the audience after the end of the discussion, which we felt indicated a high degree of interest in wood construction. The forum served to reaffirm that in Japan, where forests cover two-thirds of the land, an era that includes wood construction as an option for building mid- and large-scale multiunit housing is just around the corner. [Facilitator: Atsushi Shibuya]A Goal for Decarbonization to Halt Global WarmingCompared to the pre-industrial revolution era, the average temperature on Earth has risen 1ºC, and extreme climate events have led to disasters around the globe. We can hardly imagine what will happen if no measures are taken against global warming and the average temperature is allowed to further increase. Global warming is tied directly to the cumu-lative amount of CO2, and air-temperature increase can be controlled by managing the CO2 emissions. The Paris Agreement establishing targets for decarboniza-tion and aiming to balance emissions and absorption of man-made greenhouse gases by the latter half of this century, was adopted in 2015. Acknowledging this goal, Japan’s plans for global warming countermeasures aim to reduce greenhouse gases by 26 percent by 2030 and 80 percent by 2050.─Decarbonization Demands of Multiunit HousingWhile industry is making progress in efforts to cut emissions, household emissions continue to increase. Substantial reduc-tion of residential carbon emissions is of growing importance. Energy conservation and recycling in order to reduce the car-bon emissions of electric power, and conversion to electricity or to other low-carbon energy sources are the pillars of decar-bonization measures. Net Zero Energy Houses (ZEH) are designed for energy efficiency using high-quality thermal insulation, high-effi-ciency equipment, and power generated by photovoltaic and other means, aiming for zero or better total annual energy consumption while maintaining a comfortable living environ-ment. Various governmental agencies are currently working together to promote this trend. In urban areas, multi-unit housing, which makes a more intensive use of land than single unit dwellings, is increasing. It is ever more important to provide a high-quality stock of multi-unit housing given the high proportion of society they accommodate.─The “Wellness” of WoodCross-laminated timber (CLT) is currently the focus of much attention in low-carbon construction methods for multiunit hous-ing. Developed in Europe in the 1990s, CLT denotes both the material̶panels made of solid-sawn lumber glued together in layers with alternate layers oriented perpendicular to each other̶and the building method that uses these panels. In Europe, the use of CLT is spreading quickly in various fields of architecture. In addition to the fact that wood itself sequesters CO2, the construction process in wood produces less new emissions of CO2 compared to steel and other materials. CLT also weighs less than other building materials, meaning that less energy is required for its transportation and construction time can be shortened. Regarding seismic and fire safety, as well, CLT com-pares favorably with other building materials. The philosophy behind the WELL Building Standard that evaluates built environments for user health and wellbeing is gain-ing popularity. Some studies conclude that dwelling comfort and sleep quality improve when 50 percent of the interior surface is covered with wood. Wood construction has entered a new era.212019 SUMMER39FORUM