The question that sets the budget
It depends on how much steel has been lost and where. That single answer decides whether the repair needs an engineer's design first.
Committees ask this first and they are right to. The honest answer is that concrete cancer sits on a spectrum, and the same visible damage can be either. Concrete Cancer Brisbane does the assessment that places it.
Early carbonation damage on a non-structural element — a spandrel panel, a planter, a decorative fin — is a durability and appearance issue. The steel there is doing little work, and losing some of its section changes nothing about how the building stands up. It still needs repair, because it will keep progressing and pieces will eventually fall, but it is maintenance rather than a structural matter.
Reinforcement visibly reduced in diameter, not just rusty on the surface. A bar that has lost a fifth of its cross-section has lost a fifth of its capacity, and that is an engineering question.
Balconies and awnings carry their load through the TOP reinforcement, which is also the layer nearest the weather and the thinnest covered. Corrosion there matters far more than the same corrosion on the underside of a supported slab.
Tendons are highly stressed and a corrosion failure can be sudden rather than gradual. Any building with post-tensioning needs a structural engineer, and the inspection should establish early whether it has them.
Spalling that has reduced the effective section of a column, or exposed and corroded its ties, is structural by definition.
Even where capacity is unaffected, large areas of detached cover over an occupied space is a falling-object matter that should be isolated immediately rather than programmed.
By exposing a representative sample of the steel and measuring what is left of it, not by looking at the surface. That is why an inspection that only photographs visible damage is not enough on a building where this question is live. Where any of the conditions above apply, a structural engineer should report before remedial work is priced — partly because the method differs, and partly because a repairer should not be the one deciding whether its own structural repair is adequate.
If an inspection suggests the problem is structural, we will say so, and the repair waits for a structural engineer's design, even though that is the slower route. Patching a structural problem would be the wrong answer for the building and eventually for us.
The suburbs below cover the 1960s–80s walk-up belt and the bayside strip, where salt air can reach the steel faster.
Tell us what the concrete is doing. We will inspect it and give your committee a written scope and a quote it can actually vote on.
