In the centre of Croissy-sur-Seine there is a small castle with a park on its rear side, which will have to accommodate 3,500 m2 of high-end housing. The designed buildings allow both accessibility and visibility of the park from the long avenue. The site will remain transparent and open to the public despite the constructions. Apartment plans are made up of different layers of function. The servant area is inside (entrance and wet rooms); The area served, consisting of the rooms and the living room gives the outside. The façade is not just a unique skin that protects and filters the climate and views; it is actually made up of two layers, two facades that create between them a space that expands or shrinks according to the seasons.