This project is centered around creating a typology that supports structural experimentation with renewable materials. Part CLT factory and part structural testing facility, Testing Grounds idealizes the construction site by placing manufacturing and design spaces beneath testing surfaces for large-scale prototyping. In a novel application, the structure is supported by soft matter in the form of timber offcuts. This structural system relies on the phenomenon of jamming to perform as dynamically suited for the testing loads occurring above. This proposal is dedicated to future innovations in applying renewables to the challenges of the built environment.