Sōshitsu's mom: 畳 borders represent boundaries, and such things are the wellspring of courtesy and deference. (CQ76?)
Production
Made from Juncus effusus (Candle rush), over rice-straw bases. They have fine capillaries, which is why 畳 cool in summer and warm in winter.
Transplanted in November / December, harvested in July. Dipped in clay and water solution to seal in fragrance and colour; then sun-dried for 2 days, then weaved.
Base made from rice-straw dried for more than a year; 40 cm of rice straw beaten until it's 5 cm. One base weights about 40 kg.
Arrangement
There are auspicious arrangements and inauspicious (if there are lots of + junctions, used for funerals)
Standard tea room: 四畳半(よ じょう はん), 4.5 畳. If larger, it's called 広間(ひろま), if smaller, 小間(こま). The 四畳半 can be either.
村田珠光(しゅこう)(1423-1502) created the 真(しん)
Jōō (1502-55) the 行(ぎょう)
利休 (1522-01) the 草(そう)
Japanese
English
床畳(とこ)
mat in the 床
貴人畳(きにん)
in front of 床, for the guest of honour
客畳(きゃく)
guests
踏込み畳(ふみこみ)
in front of host's entrance
点前畳 / 道具畳
tea preparation
炉畳
炉
通い畳(かよい)
cross-through mat
Sizes
Kantō (東京): 176 x 88 x 6 cm
Kansai(京都): 191 x 95.5 x 5.5 cm; most 道具 will be designed for this size!
67 目(め), one is usually 14 mm
縁(ベリ)
無地縁(むじ)(single colour) and 紋縁(もん)(figured)
For tea room, dark blue 無地縁 is used; and a figured one in the 床
unless the room is a 小間, then for the 床 also a 無地縁 is used!