Siemens, Goa Industrial Tensile Structure

A major manufacturing operation generates a large amount of material that has to be kept dry and out of the sun — incoming components, work in progress, finished goods, packaging — and the cheapest way to lose money is to have that stock degrading in the open or under tarpaulins. The brief here was to put a genuine weatherproof roof over a very large footprint, quickly, next to a plant that never stops.

Ekra Decor delivered it as a turnkey job: survey and setting-out, 3D structural and membrane design, fabrication of the galvanised steel frame and the welded fabric, and installation and tensioning, over about 20,000 m² in roughly two months.

A roof this large is built as a repeating grid of bays. Each bay is a form-found, double-curved membrane panel spanning between a line of steel frames, and the grid simply repeats across the footprint — so the design effort goes into one bay and one connection detail, and the rest is multiplication. The column grid is set wide to keep forklift and crane movement free underneath.

The double curvature pre-stresses each panel so it stays taut under wind uplift and sheds rain to defined valley and eaves lines rather than ponding — critical over a footprint this size in a monsoon. Ekra Decor designs the steelwork to IS 800 and checks the structure for wind, rain and seismic loading to the applicable Indian codes, with the foundations sized against uplift. On a coastal site the steel is hot-dip galvanised and the membrane is a PVDF- or PTFE-coated fabric chosen for UV and salt resistance and a long service life.

A two-month programme over 20,000 m² is only possible because almost nothing is made on site. The steel frames are cut, welded and galvanised in the workshop in identical sets, and the membrane is cut and high-frequency welded into panels to a single repeating pattern, while the foundation grid is cast.

On site the work is a production line: erect a line of frames, run and tension the membrane over the bay, move on. Repeating one sequence across the grid is what turns a huge footprint into a fast build, worked around the plant’s operations throughout.

Siemens gained about 20,000 m² of genuinely weatherproof covered space — stock and operations out of the sun and the monsoon, on a clear-span structure that forklifts and cranes can work under — delivered in a fraction of the time a conventional building would take. It is a low-maintenance roof: periodic cleaning and a routine inspection of the frame and tensions.

Ekra Decor builds large-span industrial roofs and covered yards for manufacturing clients. See the related Siemens Mumbai project, more work on the projects page, or tensile structures in Goa.