Austral Building
Inspections

When the column is not the one on the drawing

A substitution nobody wrote down.

Austral 2179 · 17 February 2026

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In short: A steel column whose size and specification did not match the engineering, found at frame.

What we recorded

A column on an Austral frame that was not the section the drawing specified, and separately a connection built differently to the engineer's detail.

Why substitution happens

Availability, usually. A yard has one section and not another, and the swap gets made on site without anybody going back to the engineer.

Why it is not a small thing

The engineer chose a section for a load and a span. A different section has different capacity and different stiffness, and nobody on site is in a position to say the swap is equivalent.

The paperwork point

If a substitution is genuinely equivalent, the engineer will confirm it in writing. That letter is what should exist, and frequently does not.

Timing

Frame stage, while the steel is exposed and the fabricator is still engaged.

Written by our local inspection team from work carried out in Austral. Licensed building practitioners.

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FAQ

Questions Austral owners ask about this

Could the swap be fine?

It might well be. The point is that an engineer says so in writing, rather than it being assumed.

How would I know without an inspection?

You would not. Steel looks like steel, and section sizes are not obvious by eye.

What do you need to check this?

Your engineering. Without it we can describe the column present but not confirm it against the design.

Is this common?

Common enough that steel sections are on the standard frame checklist here.

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