Defective Pile and a False Supervision Record
A 30-storey residential tower in Kennedy Town is founded on 40 large-diameter bored piles. The AP is responsible for site supervision under section 21 of the Buildings Ordinance; the registered structural engineer (RSE) has designed a 1.5 m rock socket for each pile. Pile 23 is poured on a Friday evening. The next week, the AP's graduate assistant signs the supervision record stating the rock socket was 1.5 m. The AP later sees a site diary entry and a WhatsApp message showing that the contractor's site agent stopped drilling 0.8 m short because of a broken rig and instructed the concrete pump to top up the pile. The contractor's project manager says the pile is within the 10% tolerance and asks the AP to certify the pile and allow the pile cap to proceed. The developer says any delay will trigger a HK$1.2 million per week claim from the contractor and asks the AP not to make a mountain out of a molehill.
1. What statutory and professional duties are engaged when the AP discovers the discrepancy?
Read the worked answer
The AP's statutory duty under section 21 of the Buildings Ordinance is to supervise the building works to ensure they are carried out in accordance with the approved plans and the Ordinance. The discrepancy is a possible non-compliance with the approved pile design and a possible false supervision record. The AP should immediately stop work on pile 23 and the associated pile cap; notify the RSE and require an independent assessment, such as cross-hole sonic logging, core drilling, or load testing; secure the site records, the site diary, the WhatsApp message, and the concrete pour records; report the matter internally and to the contractor in writing; and consider notifying the Building Authority if the works are materially non-compliant or the record is false. The AP must not rely on the graduate's signature as discharging the AP's own duty.
2. Can the AP accept the contractor's 10% tolerance argument and certify the pile? Explain.
Read the worked answer
No. The 10% tolerance is not a legal defence; tolerances must be defined in the approved design and specification and accepted by the RSE. A 0.8 m shortfall in a 1.5 m rock socket is a material deviation unless the RSE can demonstrate, by calculation and testing, that the pile still has the required capacity and settlement performance. The AP cannot certify a pile that does not comply with the approved plans. The correct route is for the RSE to assess the pile, design a remedial solution if needed, and submit it to the Building Authority for approval before the pile cap proceeds. If the contractor claims the pile is within tolerance, the contractor should provide the design basis and test results; the AP should not accept an oral assurance.
3. What should the AP do if the developer threatens to replace the AP unless the certificate is issued?
Read the worked answer
The AP must not issue the certificate to placate the developer. Professional conduct requires independence, honesty, and compliance with the law; a threat of replacement does not change the facts. The AP should write to the developer setting out the non-compliance, the required investigation, and the consequences of certifying falsely. If the developer terminates the appointment, the AP should cooperate with an orderly handover, provide the records to the new AP, and notify the Building Authority of the outstanding non-compliance. The AP should also notify the professional indemnity insurer and seek legal advice. Issuing a false certificate could lead to disciplinary proceedings under the Architects Registration Ordinance, criminal liability, and personal civil liability.