In my last report Eco-Friendly Hannoks- Part 01 I described windows covered with hanji, cheoma, and maru. They were parts of hannok that regulated sunlight and temperatures. Now, I would like to explain how hannoks can control the humidity, reuse energy, and can be recycled.

           First of all, hannoks? walls are built and covered with loess, or hwangto in Korean. In other words, hannok is covered with a special type of mud. Unlike regular mud, hwangto has miniscule holes between its particles just like hanji, the Korean traditional paper that I mentioned in my last report. This not only allows air to flow through the walls freely, but hwangto itself contains highly condensed oxygen. This is beneficial because the air can control the humidity in hannoks naturally by flowing through the walls. Also, they carry out odor from the inside of the rooms.

           Second of all, I would like to point out that hannoks reuse energy. Hannoks are not heated by heaters or stoves. Instead, they are heated from the floor below. This is done in a simple yet very scientific process. First, there are rocks called ondols (warm rock in Korean) below the floor of hannoks, with a hollow space beneath the ondol. The space is then connected to a fireplace in the kitchen. When people cooked food in the fireplace, the heat floated to the space beneath the floor, and it was then transmitted to the ondol, increasing its temperature. Once heated, the ondol cooled very slowly because it was rock. In this way, Koreans could reuse the heat from cooking to actually heat the entire house. (Refer to the picture below for easier understanding.)

           Lastly, hannoks were built entirely with materials from nature that could be recycled. The walls were made of mud, and the pillars and maru were made with wood. Finally, the base of the pillars and the floors were made with rocks. In other words, hannoks were made with materials straight from nature without any procession. This made it possible for hannoks to regulate temperature, air flow, and even humidity on its own just like I mentioned before. However, it also meant that hannoks could be recycled and did not pollute the surrounding environments even if it was taken down. Most importantly, not a single nail was used to assemble the pillars and ceiling because our ancestors directly fitted timbers together by making carvings on wood.

           These are all the secrets that make hannoks not only beautiful but eco-friendly.

-Picture Descriptions-

(Photos were all taken by me at Changgeonggung, a palace in Seoul.)

1. The cheoma of a hannok, which regulates the amount of sunlight coming into the room.

2. A drawing of the ondol system.

3. A photo that shows how the timbers were fit together by carving wood.