Rusted columns supporting a house.

Rusted columns supporting a house. QBIS


Additional concrete has been poured over rusted sections of these steel columns. This is not a good idea, further rusting of the columns is causing the concrete to crack (from corners of the columns)

Preferable rectification:

  • Remove the rusted columns and its footings, replace with galvanized columns with footing platforms at least 100 mm above the soil level.
  • Fit column on top of the concrete platform, not within.

Economical rectification (if the concrete footing has been poured at or below the soil level):

  • Fit a trench to lowest point where water is most likely to pond with fall away from the column.
  • Liberally apply anti-rust treatment around bases of the columns.

Unfortunately cracks in the footings will become worse and may eventually compromise the structural integrity of the footing and ultimately require replacing, this can be very costly.

Rusted columns supporting a house 1

This is what happens after a few more years of rusting.

Larger fractures have occurred to the concrete footings that support the columns and the building. The footings require replacing at a considerable cost. This could have been avoided by fitting columns on top of concrete platforms.

Concrete pad and footing extending above the soil level.

This is a far better alternative to fit columns on top a concrete platform, not within it!

Rusted columns supporting a house. Additional notes:

  • These are good examples of why column footings must be poured in one attempt.
  • Level of concrete above the soil must be at least 100 mm.
  • Additional concrete must never be fitted to cover rusting columns, otherwise further rust will occur below them.
  • Concrete around bases of columns will trap water and cause them to rust and fracture concrete.

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