UpTiles
Biomineralized tiles with unique patterns from brick and other waste
At Uptiles, patterned tiles are created using a three-part stencil whose elements are layered and rotate at different speeds. This results in each tile having a unique pattern that only repeats every 10,000 pieces. The colors are not produced with pigments but come from differently colored mineral waste such as bricks, old tiles, or plaster debris. The tiles are solidified through biomineralization: the bacterium Sporosarcina pasteurii forms cement-like structures in the process. To sustain the bacteria, lactose whey – a by-product of cheese production – and urea are used. Urea can be synthetically produced through energy-intensive processes or replaced more sustainably by urine. However, the urine must be collected separately and kept cool, as urea quickly degrades otherwise.
| student: | Julius Zieger |
| project: | Microbial Factories |
| year: | 2025 |
Uptiles are tiles made from mineral waste such as old bricks, broken tiles, or plaster residues—materials that are locally available at almost any recycling center. These materials are crushed, sieved, and sorted by grain size. The particle size plays a crucial role in the biological solidification process: if too fine, the particles are washed away; if too coarse, they prevent effective bacterial attachment.
The natural color of these mineral residues replaces the need for synthetic pigments. This results in region-specific color palettes that make the origin of the materials visible—each batch carries the identity of its source.
The surface patterns of the tiles are created by a mechanical stencil system composed of three superimposed layers. Each layer rotates at a different speed, producing flowing, organic, non-linear patterns. The system is designed so that a pattern only repeats after approximately 11,900 rotations, enabling an impressive variety of unique designs without exact repetition.
After the tiles are molded, the biological hardening process begins. The raw tiles are sprayed with a solution containing the urease-producing bacterium Sporosarcina pasteurii.
This bacterium breaks down urea into ammonia and carbon dioxide, which increases the pH level and causes calcium carbonate (CaCO₃) to precipitate. The resulting calcite binds to and between the particles, solidifying the structure of the tile.
The nutrients required for this process are not derived from industrial sources but from existing waste streams—such as lactose mother liquor, a byproduct of cheese production, and processed urine as a urea source. The use of urine is particularly sustainable, though it must be fresh or cooled, as urea decomposes rapidly.
The mineralization process takes place over several weeks in dedicated chambers. These provide stable, controlled conditions for the growth process. Automated spraying systems and continuous temperature regulation ensure that newly forming mineral structures are not disturbed.
Uptiles bring together local resources, biological processes, and systematic design to create a product that differs significantly from industrially manufactured tiles—not only aesthetically, but also ecologically and conceptually.