Wright’s Concrete Block System

By Dempson Haney




In the early 1920’s Wright designed a concrete block system in which he referred to as the textile block system. They were featured in some of his homes such as the Millard house, Freeman house, and even Ennis house. These intricately patterned blocks were design in such a way that they could be manufactured on site with molds. Once the blocks had cured, they would be placed in position one row at a time. Steel rods would then be placed outlining the blocks both vertically and horizontally. This process would be repeated until the wall was finished. The block system suffered from numerous problems, failures, and complications. The dry mixed once cured, was porous and weak. They would deteriorate much quicker from the environment. The absence of mortar beds during erection caused blocks to come out of alignment; which was crucial since a soupy mortar mix was poured into holes between the blocks.

The process I followed was similar to that of Wright’s original plan. Using the technical innovation of digital fabrication, I constructed the molds By first modeling the block in Rhino and then extracting its contours into CAD. The laser cutter then cut out my series of layers which were then glued to form the mold. Because this is a scaled down replica of the actual system, I substituted the concrete with plaster

Different mold releases were used but the one that seemed to work the best was petroleum jelly painted onto the wood mold. After mixing the ratio of plaster and water, then letting it cure for about 24 hours, it was time to open it up. When removing the forms is when the problems occurred, the molds did not want to release. Each of the two castes broke into three relatively equal parts. The wood glued mold had peeled during the curing process allowing plaster to seep between the wood layers. This may have been caused by the heat and moisture of the plaster curing. The jelly also discolored the white plaster very slightly but was easily fixed with a couple shots of flat white paint.