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X-REED HYGROSTRUCTURES: Introducing Triply Green Building Technology

By Haresh Lalvani

"This project is a work-in-progress on HygroStructures (‘hygro’ from the root Greek word ‘hugros’, meaning ‘wet’), a new class of physical structures that conserve form, material and process. HygroStructures are formed by water and air acting on absorbent material by wetting and drying to make rigid structures. A green process.

Within HygroStructures, we show one application to X-Reed, eXpanded structures made in reed, a green material. X-Structures start from 2D and expand into 3D forms by applying force, another green process. Expanded structures build on X-Structures in metal by the principal investigator with the metal fabrication company Milgo-Bufkin as one of Milgo Experiments (1997-2014).

X-Reeds are formed by force, air and water. We present one example – 4-Way X-Reed, or 4X - as proof-of-concept of a new building technology. 4X (Plates 1-3) is a minimal structure in two ways. It has a minimal surface for the volume covered and is based on the diamond lattice, a minimal 3D lattice. Its form is minimal, a green form.

4X has a green form made from a green material using a green process, an introduces a triply green building technology. In future, we expect to apply this technology to a small experimental pavilion.

Plates 4-6 show earlier stages of development of 4X.

Since reed is limited due to available sizes and strength, our hope is to adapt expanded structures to X-Bamboo to enable larger structures in bamboo, a more resilient material with a negative carbon footprint. "

Photographs and renderings of a 3D 4-way expandable lattice structure made of reed. One image shows the object reflected on a polished surface, others display the unit in progressive expansion and isolated components. The design emphasizes minimal surface construction using a green, force-activated material method developed with hygroforming.
Photograph of a fully assembled 4X structure consisting of 10 interconnected nodes, each made from expanded reed rings arranged in tetrahedral formations. The form exhibits a lightweight, rigid 3D lattice. Shadows cast by the mesh add dimensional complexity against the background.
A compilation of photographs and diagrams showing the development of Bamboo X-POD, Phase 1—an expandable shelter structure made from bamboo and bio-fibers. Images depict the structure in flat and expanded states, its spiral geometry, hand-manipulated assembly, and interior ringed configuration. Accompanying text explains its design as a deployable, climate-responsive shelter using hygroforming techniques.
Photographs and renderings of a 3D 4-way expandable lattice structure made of reed. One image shows the object reflected on a polished surface, others display the unit in progressive expansion and isolated components. The design emphasizes minimal surface construction using a green, force-activated material method developed with hygroforming.
A storyboard-style layout of photos detailing the manual assembly of a reed structure with 3-way and 6-way expansion points. Students build and manipulate the geometries by hand. The bottom row shows a time-lapse sequence of the form being opened. Supporting text explains the use of soaked reeds and hygroforming to produce rigid mesh forms.
Interior close-up photograph of a 4X structural unit composed of reed rings and mesh, connected with white zip ties. The image highlights the layered concentric rings and intersecting lattice geometry of the expanded tubular form, offering a view through the internal passage of the structure.
Images documenting the scaled-up prototype of Bamboo X-POD, Phase 2. The structure, made from split bamboo, is shown from side, top, and bottom views in different stages of spatial expansion. Close-ups show joint wrapping details and a radial bamboo base for structural support. The accompanying text discusses fabrication methods and deployment strategy for emergency shelter use.