The exterior walls are decorated with an outstanding group of graffito. This architectonical ornamental technique used for the plaster decoration of Hispano-Muslim origin, consists on working on a revoked surface lifting the first layer according to a previous drawing (it is produced by applying two successive layers of plaster or lime with sand tinted in different colours, revealing parts of the underlying layer in contrast with the external one). The motifs are geometrical forms producing strands that frame the facings: stars inside circles, chequered rhombuses and false cushioned stalls which give a noble aspect to the walls, especially to the corner pieces. The most important ones are on the East façade: they form a valance under the central facing’s eaves, descending vertically under the draining pipes, constituted by a strip with circles and six-petal rosette in repetitive cadence, enclosed by two adjoining ones, one at each side, with rhombuses and triangles
The circular spaces or segments that crown the two side bodies are enriched with squares, circles, semicircles, and concentric arches, in horizontal or parallel rows to the arch. Two wide bands fall from the high edges to the floor, imitating a composition of stalls and a rhombuses and triangles valance frame the interior space. There is also sgraffito on the side walls of the façade, under the eaves, around the arches or framing windows, and also some recognized isolated motif such as a sun or rosette.