Thank you for commenting on yesterday's post. I see I needed to put a few more details into my explanation...
Traditional Japanese houses are wooden and have numerous uniform size tatami mat rooms set up against each other and separated by sliding "paper" doors. The rooms that have windows will also have paper shades as well as glass windows.
My house is NOT traditional though like many houses built nowadays, there is (was) one Japanese tatami room where we sit on the floor. (The other rooms in my house are pretty western though we sleep on the floor in the bedrooms.) I remember hearing a story of a Japanese/American family (wife American) who when building a house decided not to include a tatami mat room. The builder was horrified!
"Where will your husband officially greet your future son-in-law if he doesn't have a formal Japanese room to sit in?"
Tatami mats are uniform in size and a Japanese room will be measured by how many mats can be laid out. A mat is about the size of a small narrow door. Our Japanese room has 6 mats. That is normal. Larger rooms will have 8 mats. Poor working college students will live in a 4 1/2 mat apartment (and that's all there is! 4 1/2 mats.)
(This is a apartment floor plan I took off the Internet. You can see the two 6 mat rooms, a 9 mat living room/dining room/kitchen with flooring, one closet in orange, and a bathroom.)
At the end of the year, another job for a traditional Japanese family might be to have their Japanese mats refurbished, but this is a job for a professional, not one that someone will do themselves. Mats are made of packed rough straw blocks and then thin woven reed/straw mats are sewn to the top. When a top mat wears out, it is flipped over to the back side and resewn to the rough blocks. And when the top reed/straw mat is beyond use, it can be replaced. Another nice thing about tatami mats is that when one gets worn looking (for example in front of the door), the whole block can be shifted to another spot and a less worn mat laid down in its place. Tetsu removed our mats entirely a few years ago after numerous cat accidents. (There are some pictures of our removed tatami mats on those links above.)
Paper doors between rooms and on the closets, are also lightweight and removable and it is supposedly fairly easy to replace paper that gets stained or worn. There are always lovely oriental looking designs on paper doors... Mt. Fuji, flying cranes etc. I've never changed the paper on my doors (though they need changing.)
And then there is the light, white paper on the windows that I changed yesterday. Tetsu came home early and when I told him I couldn't get the one wooden lattice off of its rails, he LIFTED the top railing (supporting the second floor!) and with a lot of grunting and pulling on both our parts, we were able to get the lattice out and later back in. Tetsu! My hero! Like SUPERMAN! Lifting a house!!!
When Tetsu and I were engaged to be married, my American family and friends asked what they could send as wedding gifts.
"What color are your walls going to be? Your carpet? Your curtains?"
"Ummm. No walls (just the sliding doors). No carpets. No curtains..."
"Tanya! What kind of house are you going to be living in?!"