Porcelain in Presence

Abstract

Ceramic sanitaryware is among the most thoroughly engineered materials in a building , strong, chemically stable, made to last , yet at the end of its life almost all of it is crushed into aggregate or buried. The problem is not that the material has lost its value, but that recycling systems have no means of carrying that value into a usable architectural product. This thesis asks how that gap might be closed: how discarded sanitaryware can be reformulated into a castable ceramic body, how processing shapes the surface that results, and how people read and accept that surface once they know where it came from.
The work pursues two strands in parallel, one in material engineering and one in human perception. The first develops a recycled-sanitaryware slip-cast body through a stage-gated process , testing feasibility, particle-size control, binder selection, and the transfer from surrogate waste to toilet-derived material , drawing on specific gravity, particle-size distribution, water-to-solids ratio, and casting behaviour to identify workable formulations and practical waste limits. The second traces acceptance across three phases: baseline attitudes, tile perception, and a food-contact object.
On the material side, castability at high recycled content proved to depend not on waste percentage but on the engineered control of packing and cohesion. A standardised sieving protocol was essential , apparent grading shifted sharply with shaking time alone , and a fine-shifted packing strategy with low-dose PVA binding produced a robust 50% toilet-waste body that reached the lowest water-to-solids ratio and the strongest casting behaviour in the comparison, 60% marked the practical limit and 80% a deterioration zone. The high-waste bodies also remained castable from broad, loosely sorted gradings, which affords the process latitude and lowers the energy spent on fine sorting.
On the perception side, acceptance proved conditional rather than absolute. Participants were broadly pro-sustainability, yet hygiene, food contact, origin wording, and disclosure all acted as gates. In the tile study, knowledge of the recycled origin was the strongest driver: it divided judgment, so that the same surface read as more recycled and authentic but less clean, while geometry and waste-level differences were not significant, kitchen acceptance was predicted by perceived control, interior acceptance by visual pleasantness. With a cup in hand, willingness to drink remained high , recycled sanitaryware is not rejected outright in intimate use , yet acceptance narrowed in food-preparation contexts, under blunt "toilet-derived" wording, and where the origin had to be disclosed to others.
The research ultimately shows that the challenge of reusing sanitaryware extends beyond material recovery alone. Whether recycled sanitaryware can re-enter architecture depends not only on how it is processed, but also on how its resulting surfaces are perceived and interpreted. Material history, process design, surface expression, and human acceptance therefore operate as parts of a single system rather than as separate technical and social concerns. The findings demonstrate that sanitaryware waste can be reformulated into viable ceramic bodies at substantial recycled-content levels, but that successful implementation relies on carefully balancing technical performance with perceptual acceptance. In doing so, the thesis proposes a materially grounded pathway for moving sanitaryware beyond downcycling and toward value-retaining architectural reuse.