The lightly structured fence that extends from either side of the Baikenmon gate is called Zuiryugaki. Passing through the gate brings one into the inner tea garden (roji). It is not large, but has the quietness of a place in the depths of the mountains. On the right is the inner waiting arbour and next to this is the lavatory. Small stepping stones lead to the tsukubai (stone wash basin), then to the nijiriguchi (crawl-through) entrance to the tea room. The wash basin was made from a foundation stone and has been used since the time of Shoan.

From the outside Fushin'an makes one think of a house in the mountains, with its light, rustic feeling. It has extended eaves in front and to the side of its small, shingled kirizumayane (shaped like a half-opened and inverted book) roof, making the whole structure lower. Inside it has three guest mats and a daime (smaller-sized mat) for the host. The toko is right in front of the nijiriguchi (crawl-through entrance) and there is a katoguchi (arched doorway) in the wall next to it that is plastered round at the corners. Above the guest mat only half of the ceiling is horizontally surfaced and the other half is a slanting kesho yaneura. There are lattice windows and shitajimado (frameless windows with the interior bamboo latticework exposed). A skylight is cut into the roof, to enhance the stage effects of the tea gathering.

The hearth is between the host and guests (daimekiri), and there is a nakabashira (central pillar) in the corner of the hearth. There is a sodekabe wall extending from the main wall to the central pillar and a two-level suspended tana (shelf). This kind of layout for a room is called daimegamae. The sodekabe wall does not extend all the way to the floor, being framed at the bottom by a length of bamboo, so the guests can see the arrangement of the utensils beneath it. The straight pillar of red pine with the bark left on is strong, although it is slender, and acts like the central pillar of a house. The area around the central pillar creates nostalgic memories of sitting in a happy circle around the hearth in a private house.

It is a special characteristic of Fushin'an that the sadoguchi (host's entrance) is on the other side of where the brazier is placed on the host's mat, and a board beside the host's mat makes it easier to go in and out of the room.