Palm-wood roofing

The composite earthen-roof assembly characteristic of southern Moroccan vernacular building. Primary beams of palm, tamarisk, or juniper span between bearing walls at intervals of roughly 30 to 50 cm; a closely-spaced secondary layer of palm ribs (jrid), reed matting, or split tamarisk is laid perpendicular over the beams; over this is poured a thick bed of earth, sometimes mixed with straw and lime, which is rammed and finished as the stah terrace. The assembly performs all the functions of a roof — load-bearing, weatherproofing, thermal mass — within a single integrated layer, and its periodic repair is one of the principal maintenance demands on a living kasbah.