Volumetric Envelopes: Precast elements in building envelopes

By supplanting survival with comfort, the environmental technologies ultimately increased the dependence of the building design on form and materials, particularly those of its ‘envelope.’ The emphasis on form and materials is best seen in the Brutalism Architecture where the “honesty in structure and material” is exhibited through the envelope. Brutalist is relevant to today’s digital fabrication techniques where materiality and fabrication methods are integrated with the realized building elements. For example, looking at 3D printed concrete, parallel and continuous layers of concrete placed on top of each other can be an indicator of the method, whereas seeing a smooth curved surface in a cast part can be an indicator of employing the molding method.

Casting a malleable material such as concrete has multiple steps: creating a positive reference part, conceiving the formwork as the negative of the desired part, then pouring the liquid concrete, and finally demolding the hardened part. By employing 3D printing for creating the formwork, the first step of this process can be eliminated. In addition, limitations that a wood or steel formwork may impose on the part can be lifted.

This paper looks at concrete elements used in building envelopes. It also reviews some recent projects regarding the design and fabrication of these modules with an interest in sculptural volumetric elements. It then provides an overview of students’ projects designing a volumetric self-standing shading screen using computational design tools and digital fabrication techniques, specifically 3D printed formwork. The pedagogy investigates challenges that students faced to break away from designing a “brick” mindset to designing topologically interlocking elements. The pedagogy demonstrates the complexities and opportunities that today’s advanced fabrication methods such as 3D printing can offer designers.