Structural steel framing

One beam, or the whole building

Steel does the work that timber cannot: long spans, heavy point loads, and openings wide enough to drive through. We design structural steel across that whole range, from a single beam acting as a lintel over a garage door through to a large-scale portal framed warehouse, to Australian Standard AS4100.

Most residential jobs land at the smaller end — a beam to carry an upper floor over a wide opening, a post and beam to open up a rear elevation, a lintel above a new window. The principle does not change with scale. Work out what the member has to carry, then size it and detail how it connects.

What actually sizes the steel

Span is the obvious one, but it is rarely the governing factor on its own. The load path above matters, and so does deflection — a beam strong enough to stand up can still sag enough to crack the plasterboard hanging off it. For sheds and portal frames, wind is usually what governs, and the design has to account for the wind region and terrain applying to the site.

Connections deserve the same attention as members. A correctly sized beam sitting on an inadequate support has simply moved the problem.

Typical work

• Lintels and beams over new or widened openings
• Post and beam framing for extensions and alterations
• Portal framed sheds, workshops and warehouses
• Mezzanines and supporting steelwork
• Connection design and detailing