A house made with natural materials in Yokohama / 横浜市泉区【自然素材の家】 Part 2
Hello there, we are happy to announce the completion of the Tatekata. The pine beams we worked on manually (not pre-cut materials) have fit perfectly with each other as well. Very happy.
We are working on the roofing currently, with the natural material of Japanese cedar boards. As the ceiling style of the upper floor of this house is a sloped ceiling, there will be some aerated zone to improve the thermal insulation performance. With the sloped ceiling on the upper floor, it tends to get quite hot during summer time. This is why it needs the aerated zone between sloped ceiling and the roof to prevent the heat coming from the roof from going inside.
This method is relatively new in Japan and I believe the original idea comes from traditional method of monitor roof (Koshiyane) It normally has a little window on the highest spot where the heat/smoke can escape from as well as a place where lights can come in from.
This was a people’s wisdom back in days of no air-conditioner to keep the house cool and comfortable. I think this is very similar to the method we are using today. I always mention the importance of the traditional method but it is also important to seek new and improved.
Thank you 🙂
木造2階建ての新築工事の投稿です。
先日無事に棟が上がり、上棟式を行う事ができました。手刻みした松の梁もピシャリと納まりひと安心です！現在、屋根工事を行っています。屋根に張る板はもちろん自然素材の杉板です。今回、2階の天井は勾配天井となりますので、屋根に通気層を設けます。
＊勾配天井の説明は上の図を見てください
断熱性能をあげる為です。2階の天井を勾配天井にした場合、どうしても夏の2階の温度は高くなりがちです。そこで勾配天井と屋根の間に通気層を設けることにより、屋根の上から2階の部屋に伝わる熱を逃がしてくれます。この工法は比較的新しい工法ですが、とても良いと思います！
この工法の原点となったのはやはり日本の古い民家だと思います。民家には越屋根という屋根があり家の1番高いところに窓があります、そうです熱気を外に逃がすための窓です。（ほかにも光を取り入れる、煙を排出するなど）これはエアコンもない時代に家の中の暑い空気を逃がして快適な空間にするための日本人の知恵です。この通気工法は越屋根に似た考え方だと思いました。
古くから伝わる伝統構法ももちろん大事ですが、新たな工法を取り入れることもこれからの家づくりにとても大切だと思います！
