Tensile and membrane canopies in Bali

The work covers restaurant terraces, pool decks, entrance canopies, event pavilions and parking — spans from a four-metre umbrella to well over a hundred square metres above a dining room. Masts, arms, plates and cable ends are fabricated in our own workshop and hot-dip galvanised before coating, because on this island it is the connection that corrodes, not the fabric. Footings are sized for uplift, which on a canopy is the load that decides everything.

Fabric choice is where honesty saves money. PVC-coated polyester with a PVDF lacquer at 900–1,100 g/m² is the sensible default here: ten to fifteen years of service, weldable, repairable and cleanable when the algae arrive. Knitted HDPE shade cloth costs a fraction and makes a perfectly good sun screen, but it is not a rain roof, and anyone selling it as one is arranging a puddle over your guests.

Wind, not weight, sizes the structure

A membrane canopy weighs almost nothing, which tempts people into treating the footings as an afterthought. The governing load is uplift: a gust catching the underside of a 60 m² canopy pulls upward at every mast, and the collapses we get asked to repair are nearly always foundations and baseplates rather than fabric. We calculate reactions for the real exposure — an open beachfront at Cemagi is a different problem from a walled courtyard in Ubud — and pour footings that match those numbers.

The other half of the calculation is drainage. Bali delivers 80–100 mm in an hour often enough that any flat spot in a membrane becomes a hundred litres of standing water, which stretches the fabric, deepens the pond and finishes the job. Double curvature plus a defined low point with a real outlet is what prevents it, and both are decided at form-finding, long before a panel is cut.

What a membrane actually costs to own

A PVDF-lacquered PVC membrane in this climate gives ten to fifteen years before the coating surrenders, and it does so gradually: surface chalking first, then staining, then weakening welds. Budget a wash every year or two, a retension around year three, and a replacement skin somewhere in the second decade. That is the whole cost of ownership, and it is far cheaper than the steelwork holding it up.

PTFE-coated glass fibre runs twenty-five years and looks better doing it, but fabrication is specialist and the price roughly doubles; it belongs on hotel-scale landmarks and rarely on a villa terrace. Where the brief is shade rather than shelter, knitted HDPE at a quarter of the cost is the honest answer — as long as nobody pretends it will keep the table dry.