Exterior, House Building Type, Metal Siding Material, Flat RoofLine, Brick Siding Material, Glass Siding Material, and Mid-Century Building Type In the entrance, a team with the general contracting firm Martha uncovered an abstract mural that Engels painted himself and then plastered over. He also made the geometric door handle. Simon speculates that Engels sourced the marble, found all over the house, from Expo ’58, after the pavilions had been dismantled.  Best Photos from A Major Restoration Updated This Midcentury Landmark in Belgium