Steel structures and roof trusses in Bali

The two systems we build with answer different questions. Light-gauge galvanised truss — the C-profile system now standard across Indonesia — is quick, dimensionally accurate, of no interest to termites and ideal beneath tile or metal on residential spans. Hot-rolled sections take over as loads, spans or exposure grow: portal frames, mezzanine floors, pergola and canopy structures, and anything expected to carry plant or a planted roof.

Corrosion sets the specification long before strength does. Within a couple of kilometres of the surf, unprotected steel starts pitting within months, and a painted section detailed with a water trap fails from inside the trap outwards. So we hot-dip galvanise wherever budget and geometry allow, use a measured primer and topcoat build where they do not, seal hollow sections, drill drainage where water would otherwise sit, and isolate steel from aluminium and stainless at every point of contact.

Light-gauge truss against hot-rolled steel

The galvanised C-profile truss system covers most residential roofs on this island for good reasons: light, precise, factory-coated, delivered in a small truck and erected in days. For spans up to roughly twelve metres carrying tile or metal sheet it is normally the economical answer, and unlike timber it holds no interest for termites. Its limits show when point loads appear — a heavy air-conditioning unit, a solar array, a service-laden ceiling — or when the architecture wants structure worth looking at.

Hot-rolled steel handles those cases. Universal beams and columns, hollow sections and plate connections carry longer spans, cantilever properly and can be detailed to look deliberate. It costs more per kilogram, needs craneage or a written lifting plan, and demands serious corrosion protection. Where a project could reasonably go either way we quote both, with spans, coating specification and erection method written down, so you are comparing buildings rather than rates per kilogram.

Welds and coatings you can verify

Two things separate steel that lasts from steel that stains a building. First, welding: correct consumables, proper joint preparation and welders working to a written procedure. Our fabrication happens in the workshop wherever the geometry allows, because a weld made under cover on clean, dry steel is a different object from one made at height in the wet season. Site welds are limited to defined connections, ground back and coated the same day they are made.

Second, the coating system. Hot-dip galvanising gives decades in Bali's air and is our recommendation for anything coastal or exposed. Where galvanising is impractical — very long members, later modification, an architectural finish — we specify a blast-cleaned primer and topcoat to a stated film thickness and check it with a gauge rather than by eye. Either way the protection specification appears on the quotation, not in the hands of whoever holds the spray gun.