Molenaar’s paintings show architectural structures, interiors, or faces of conceived buildings, and all rooms and environments come along with a certain blankness. There are no people, no properties, nothing that allows the viewer to interpret the scene. As the artist explains his passion for these buildings: "Just like us human beings, a house has a certain character and arouses different feelings and emotions". To create a balance of the inner and the outer, of being open and being closed, and of feeling security or claustrophobia, is what Molenaar is most interested in. In case of the buildings, the bridge from the one stage to the other is represented by the windows. They raise questions of "Who am I?" and "What do I see?". However, Molenaar does not want to answer those questions too precisely, because he thinks that a good painting should hide more than tell.