The Coignet house, completed in 1853, was the first concrete construction in France. France. Now in ruins, it is located in Saint-Denis, on the banks of the Seine, in a neighborhood undergoing major changes. The risk with such a site would have been to make it a heritage site, isolating it from the very complex urban context in which it is located, which is characterized by land pressure and an urgent lack of parks and green spaces.

Given this urban context, the project I proposed consisted in securing the very damaged building, by keeping only the four exterior walls, maintained from the inside thanks to a wooden frame. This choice made it possible to preserve the original concrete of the Coignet house, while avoiding the cost of a complete renovation. Once maintained and secured, the ruin of this historic building was integrated into the development of a small park of more than 4000 m² available to the inhabitants of Saint-Denis.

Coignet House Current condition of the Coignet House as seen from the west of the site, which is being colonized by Tree of heaven (Ailanthus altissima)

Coignet Sketch by Clément Gaillard Research for the park design

The main challenge of this project was to preserve the Coignet house and its characteristic clinker concrete without renovating it. All my research was focused on the interior structure, the use of wolf jumps for the protection of the ruin and the design around the house.

J’ai aussi particulièrement étudié la liaison entre les deux rues qui bordent la maison Coignet. J’ai finalement privilégié un aménagement minimal et près du sol, composé d’assises et de marches en béton brut de décoffrage, disposées aux abords de la maison.

Coignet Park Research by Clément Gaillard Perspective for the study of the accesses to the park of the Coignet house

The exterior layout and seating alignment follow the plan of the interior of the Coignet house. The circulation between the two levels levels snakes around the house and follows the line of old stairs. In addition to protecting the house and keeping visitors at a distance, the challenge was to ensure a pedestrian link between the two streets that border the site.

Coignet Park Plan by Clément Gaillard Plan of the park of the Coignet house

Coignet Park Plan by Clément Gaillard Section of the park of the Coignet house along the axis AA'

Coignet Park Plan by Clément Gaillard Final perspective of the park of the Coignet house