Installations in walls

Thomas Staub

Wall heating: the walls are covered by a layer of hydraulic plaster against which the tegolae mammatae are attached with iron nails, which are placed at the corners of the tiles through the protruding parts (the mammatae), thus creating a ca. 0.05 m wide hollow space, through which the heated air, coming up from the hypocaust system under the floor, could circulate. The tegolae mammatae are ca. 0.52 x 0.52 m large and 0.025 m thick, the mammatae are protruding for ca. 0.05 m.