Prototyping Thatched Facades—Global Scaling of Local Knowledge

The paper presents the results from a cross-disciplinary research project investigating clay as a fire retardant in vertically thatched facades, and it elaborates on its consequences on aesthetics and buildability by prototyping. The prototypes take point of departure in three different typologies: thatching on construction sites, thatched prefabricated façade elements, and thatched masonry. Initially, a mock-up of a reed-thatched façade sprayed with clay and with clay boards as fire stop every 100 cm was subjected to a Single Burn Item test (SBI test). The result showed a FIGRA at 25 W/s, which is positive. This raised the question on how these findings could form radical tectonic solution as a respond to the need for CO2 neutral constructions. The prototyping of prefabricated clay-impregnated thatched façade elements seems to have multiple possibilities regarding time optimization, transportation, and (dis)assembly. Whereas thatching and impregnating on the construction site is possible, but slower than standard thatch construction therefore processes must be developed and tested further. An unanswered question is how the reed will respond to humidity, when thatched to a solid base of plywood without ventilation. Furthermore, questions about the ceramic curing of clay when burned with downfall as a result are unanswered.