What a parapet is
A parapet is a low wall formed by carrying the outer wall of a building up above the roof edge. The word originally meant a breastwork along a rampart or the rail of a bridge that stops people falling, and in architecture it covers any upstand around the edge of a roof.
It has two main roles. One is to enclose a flat roof, keeping people on the roof from falling and finishing the edge of the waterproof membrane. The other is visual: raised high on the front of a building, a parapet hides the pitched roof behind it from the street and gives the building the look of a flat-roofed Western structure. Some early Showa shops were finished this way, with only the front of a timber building treated so.
The top of a parapet is usually finished with a coping to shed rain, often with a stepped projecting cornice.
Reading the records and the building
Records describe the form and purpose of the parapet. The main house of the Okuyama family in Nishiyodogawa, Osaka, a fuel dealer's shop and residence, is recorded with parapets of varying height raised to make it look flat-roofed, scratch-tile cladding and a canopy shaped like a cornice, all efforts toward a Western appearance. The roof itself is pitched, and the parapet hides it.
Other examples pair it with a true flat roof. The bathhouse of the former Matsui family villa in Wakayama is built of brick with a reinforced-concrete roof slab, and a parapet with a cornice runs along the top of its walls. The record for the former receiving-well house at the Sue water purification plant in Kanazawa says that a parapet carried out on gentle curves defines its elevation, the parapet itself becoming the main feature of the design.
On site, compare the front of the building with its side. If the front looks flat-roofed but a pitched roof appears behind it when seen from the side, the parapet is screening the roof.
References
- 末浄水場旧着水井上屋｜国指定文化財等データベース（文化庁）
- https://kunishitei.bunka.go.jp/heritage/detail/101/00011283
- 奥山家住宅主屋｜国指定文化財等データベース（文化庁）
- https://kunishitei.bunka.go.jp/heritage/detail/101/00004145
- 旧松井家別邸（がんこ六三園）浴室棟｜国指定文化財等データベース（文化庁）
- https://kunishitei.bunka.go.jp/bsys/maindetails/101/00009365
Last verified: 2026.09.26