Building supports rusting

Rusting of building supports. Identified by Peter Weddell, owner/operator of Qld Home Buyers Inspection Service and Queensland Building Inspection Service, QBIS.

Supports rusting below a building

Another supporting steel column that has rusted way beyond repair.

Footings must extend at least 100 mm above the soil level, this is a building code of Australia requirement.

Rusting of building supports

Water has accumulated around the base of this steel column causing significant rusting.

Significantly rusted steel column supporting part of a veranda.

Cause of problems:

Stormwater runoff from adjoining properties is causing ponding of water around the column bases.

  • Water is ponding around bases of the columns causing them to rust
  • The footings are also fracturing from the rusting columns within the concrete.
  • This is a major expense to replace

It is highly recommended replacing the columns with hot dipped galvanized columns with concrete mounds around their bases. These have a far greater life expectancy.

This shows the importance of drainage and stormwater systems around buildings.

Recommendations on rectification:

All examples of rusting columns in these photos require replacing and most likely the concrete footings they are incorporated in.

  • I would recommend creating a concrete platform with its top side being at least 100 mm above the soil level and bolt the columns to the platform.
  • This will stop water from ponding around bases of the new columns and future rusting.
  • Drains may also be required to allow accumulated water from low lying areas of the sub-floor. This allows water to escape beyond the sub-floor to a lower point on the property or to the street gutter.

Water must not pond around bases of steel columns this will accelerate rust.

Building supports rusting. Related information that may be helpful:

Qld Gov, stormwater, runoff and drainage information

For independent Building Inspections Brisbane in all suburbs, Qld Home Buyers Inspection Service.