Cheap Foundation Piling Budget Screw Piles - Non-Engineered Crap


We are sick to our back teeth at the mentality of some builders in WA and I have a question for them: What price do you put on screw pile product that is designed manufactured installed in accordance with REAL engineering design & installation certification which is all under audited Quality Assurance?

Do we sound pissed off? Well we are. Here's why. Some Perth builders, particularly project builders simply don't understand what constitutes a certifying design engineers, Pile Design & Installation Certification. In particular, we're talking about screw piles used for domestic housing. WA's domestic builders & a sector of WA's consulting structural engineering fraternity seems unable or unwilling to rectify and control this ridiculous situation. Think we're out of control in making such a statement? Then we welcome you to contradict us on the following as we would love to be proven wrong & will publicly apologise on Linkedin.

In addition to what is outlined below, keep in mind that WA is the ONLY STATE IN AUSTRALIA where an individual can design & install piling, ground-anchoring, deep soil stabilisation & retention without any experience, qualification or licence and get away with it. A car salesman could come along tomorrow, claim to be an expert in piling, design a so called solution & install same? You need a licence to sell used cars in WA, but you don't need anything for piling & stabilisation design or installation. Don't believe me? Check out the Govt website: State by State Foundation Work Qualifications. Type in a supervisor for Foundation Work & you'll get: Current licence in QLD: Equivalent licence in WA: Foundation Work (Piling and Anchors) Licence - Site Supervisor Grade Not licensed in WA. Thats just one example.

                                   Competitor's Screw Pile

Now to the facts in what constitutes CPEng. "Piling Design & Certification" & what's necessary to comply with the Australian Building Code, Australian Standards and Professional Engineering Guidelines & Principals? This recent extract from an Engineers Australia document currently trying to address this very problem is a good start:

The specific requirements for any certification will be determined on a case-by-case basis. This may or may not require a certification to be in a particular format and to address certain things.

However, by way of general principle, a certification should be:

1.    Accurate

2.    Clear and precise about what is being certified (and if appropriate - what is not)

3.    Limited to what is known

4.    Exclusively reflect engineering considerations

5.    Based on appropriate evidence to the positive satisfaction of the CPEng.

6.    Importantly, a requirement for certification and certification itself are not the same. Where a contractual or other requirement specifies that certain certifications be made, for instance, that an ‘as built’ structure complies with an approved design, that certification would not be accurate if it does not. Where there have been changes, but it meets the ‘design intent’, then that would be the appropriate and preferential certification. Put simply; any certification must reflect the underlying engineering reality.

Lets look specifically at WA. Just about everybody in the WA industry will have seen, at one time or another, these "generic pile details" for project builders that are bandied around. Everybody believes this to be an engineering certificate or a certified piling design. Rubbish. Next time you see one of them use the points above & see how it stacks up? How does a generic screw pile detail that doesn't show a specific screw pile CHS section design, a minimum design load, an installation eccentricity tolerances, a minimum design life, a minimum installation torque, an interface connection, etc. etc. etc. constitute engineering certification? It doesn't. More recently these signed generic pile design details carry the following notation: "Screw pile design to manufactures specification". That comment transfers responsibility for pile design & installation outcomes to the screw pile manufacturer/contractor. So why isn't site specific screw pile design & installation certification provided by these budget screw piling operators? Simple. Not only don't they have the resources, they don't have an understanding of what constitutes Australian Standards & CPEng compliant engineers screw piling certification. All they know is how to wind in a screw pile. They have constructed the false industry perception, that the original generic signed pile detail is engineering certification and thats misleading at best.

So what constitutes certified engineering piling design & installation certification? Firstly, correct certification must cover the design in its entirety and the installation outcomes. Miss one, the lack of that one cancels out the validity of the other. So miss the installation certification part of the equation and the original pile design certification is worthless. Moreover, if the design certification fails to specify all the design elements then the original is not even worth the paper its written on. Pretend your in Court trying to substantiate who was responsible for the design & outcome where Foundation Piling or Shoring has failed?

PART 1. - Engineers Piling Design Certification must include:

  1. Site Address
  2. Any Adjoining Services Details
  3. Allowable Pile Design Loads (compression, tension, bending moment, lateral)
  4. Allowable Screw Pile Eccentricity
  5. Screw Pile Specification (CHS yield strength, shaft section size & thickness, helix number/size/thickness/yield/pitch/welding/coating
  6. Geotechnical parameters that the pile design is based on
  7. Minimum Screw Pile Design Servicability Life (corrosion allowance criteria)
  8. Minimum Screw Pile Embedment
  9. Minimum Installation Torque
  10. Screw Pile Layout Detail Drawing
  11. Screw Pile Interface to Footing
  12. Footing/Ground Beam Design & Detail
  13. Installation Criteria (installers qualifications)
  14. Future Proximity Excavation Criteria
  15. Statement of Australian Building Code & Standards Compliance 

Part 2. - Engineers Installation Certification is to include:

  1. Site Address
  2. Cross Reference to the Original Engineers Piling Design Certificate
  3. Screw Piling Installation Contractors Details
  4. Reference to Piling Contractors Installation Logs (inc. subsequent load testing results if applicable)
  5. Engineers statement confirming the review of the screw pile installation logs and subsequent compliance to the engineering design & intended outcomes in line with Australian Standards

So why isn't the above part of WA's domestic housing piling & shoring engineering certification process? For more information on this issue please contact the Foundation Engineering Group on +61 (0)8 9371 7711 or Email us here. Get it right the first time.


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