In the Red Flat, the generous living space stretches obliquely upwards into the private area in the upper floor. There is a strong relationship with the exterior, through the glass façade, the balcony and the curtain device, working as a filter. The city enters the room at the wish of the user. The inhabitants can manipulate the curtain manually interacting with it directly, according to their desire of privacy, light, exposure. Thus, the user can take advantage of the performative effect of opening or closing, exposing more or less their domestic life.