Hiroshima City Planning chose the design from a competition to be the standard. It is the unique public project that approximately 5 restrooms are mass-produced in parks per year as regular design of the city
First of all, I considered that what should embed in “city”. I was aware of designing “multitude” strongly, which is not “a ” restroom in a park. And they should be given a meaning as a whole of the infrastructure in the city. I aim to make an absolute axis in the city by being embedded the direction in infrastructure building in the city. The mass-produced urban facilities have a triangular roof pointing north. By building in same direction, each restrooms have same space by sunshine. The same space of restroom is omnipresence all over Hiroshima.
I designed 3 variations of plans in this project. I provide with 2 entrances of east and west side, so that the plan is able to turn the other way around as it functions whichever entrance. Structure of the restroom is box frame type reinforced concrete construction. The roof is also made by concrete. Concrete is poured by the ruler of stainless steel in the edge of the acute angle part of the roof. The roof finishes by a fluoric resin topcoat after FRP waterproofing. Therefore it is possible to put the different color every roof of the restrooms. Each location has a different color roof that matches the playground.
I incline the roof, the north side is high, the south side is low, to be able to look at the roof facing north from eye-level. A slit-shaped top light goes to the south and north in the center of the roof and creates lines toward north inside and outside of space. Acrylic lighting windows and round ventilation holes in eastern and western wall, and acrylic lighting windows in southern wall, are inlayed. They function that controlling the environment of the internal space. For the finish of the outer wall, I adopted the photocatalytic coating paints that the dirt is easy to come off.
22 restrooms in 22 parks are completed in March in 2012. It is built around five places sequentially every year. The public restrooms with absolute arrows are being embedded infinitely in all over Hiroshima-city.