Japanese woodworking - Indirect Lighting Installation

Hello, this is Shoyan, a Japanese carpenter. Today, I'll install curtain boards and ceilings of indirect lighting above this window. First, let me explain about indirect lightings. I'll install another ceiling below this existing ceiling. The lighting will be installed between those two levels of ceilings. The lighting will be invisible from people in the room, but it will illuminate the room indirectly. That is what indirect lighting is. Indirect lightings were more popular approximately 40 years ago. Around 30 to 40 years ago, a drawing room surely used to be made in regular houses. Nowadays, drawing rooms are seldom made in houses. Design of drawing room ceilings are always complex with difficult ornaments. For example, bumpy walls, level gaps of ceilings, and so on. At that time, indirect lightings are often used for drawing rooms. Later, this kind of indirect lightings has not been made for a while. But these days, this kind of indirect lightings are getting popular again. Okay, let's put the old story aside. Install the substrate materials of ceilings. The upper ceiling is already installed, and it's horizontal. So, measure the level based on the upper ceiling and decide the height of substrate materials. The lower ceiling is only 600mm in depth. It's a low ceiling of 4m in length and 600mm in depth. The materials of the ceiling are plain cedar boards. I'd like to fix them towards the short side direction. So first, install substrate materials towards the long side direction. Okay, no substrate materials are fine. Next, measure the dimension of curtain boards and cut them. Curtain boards are also cedar materials. They are made of only akami portion and quarter grain. Check the length at the position by fitting. The length is fine. So, let's fix it by glue and screws. This curtain board has a groove at the bottom. So, put a cut-off piece to check the level. Then, fix it from the back side by screws. Wipe overhanging glue clean and fix the curtain boards to be straight. Without fixing it tightly, it will be curved while fixing ceiling boards. Cut ceiling boards of cedar materials. These cedar boards are 12mm thick. This ceiling is low enough to reach. So, take care of colors of cedar boards to match the color. And choose a white portion of materials that is called shirata. Some boards are not from shirata portion that is called akami. Then, use akami portion at both ends. And use shirata portion at the center so that the center of ceilings looks light and the ceilings will not be mismatching in color. Now, I'm checking the dimension of whole of the ceiling. It's better to place the materials on a line actually and adjust the layout from the center and decide the dimension of the boards at both ends. Based on the layout, cut the boards. Fix the boards by wood glue and 4mm tackers. Check the angle of 90 degrees carefully when fix the first board. If the first board is misaligned, the whole portion will be misaligned. So, check the angle of the first one carefully. Install the bottom board to fix lightings. Without the bottom board, electric equipment vendors cannot fix the lighting at this position. Current lightning equipment doesn't generate heat. But make it wide just in case. Fix the same boards as was on the front side. Now, I'm fixing only wall boards of 12mm thickness. After these boards, plaster will be applied on the wall. The walls will be finished with white plaster. Next, apply glue along the joints of wall boards. By this glue, the wall boards will be integrated. The cracks can be prevented. There are no enough spaces at lower side to fix boards by tacker. So, I fix them by screws. I've completed the install curtain boards and ceilings of indirect lightings in quiet tones. That's all for today. Thank you for watching.