Fracturing of new concrete stumps, in Wavell Heights, North of Brisbane
These new concrete stumps were replaced approximately 4 years before an inspection and are already fracturing.
Courtesy of Peter Weddell, owner/operator or Qld Home Buyers Inspection Service and Queensland Building Inspection Service, QBIS.
Common causes of stumps to fracture:
- Water entry and ponding.
- Rising damp.
- Salts in the soil.
- Reinforcing being too close to the concrete surface.
Often concrete stumps are not the correct product to use. This is dependent on different circumstances.
- Steel columns (preferably hot dipped galvanised).
- Reinforced block piers.
- Better still, believe it or not, timber stumps.
Telltail signs of problems starting:
Severe fracturing to this concrete stump from it’s reinforcing rusting internally.
Rising damp and salts in the soil are also causing deterioration to the concrete stumps.
Misconception of timber stumps:
The majority of home buyers are under the misconception that the lifespan of timber stumps is not very long. Believe me, from experience, treated hardwood stumps (when correctly installed) are more likely to outlast all of the others, including you and me!
Downside of using timber stumps:
Timber is more expensive. Also because most homebuyers (from lack of experience) do not realise the longevity of timber stumps, this may have a negative effect when selling your house.
New concrete stumps fracturing. Important points.
- Depending on the type of soil, concrete stumps are not necessarily the correct choice.
- Timber stumps, piers or steel columns should also be considered.
If using steel columns, they must be hot dipped galvanised, with the concrete footing extending at least 100mm above the soil level. This will help stop premature rusting around their bases.
For independent Building Inspections Brisbane in all suburbs, Qld Home Buyers Inspection Service. qbis.com.au