Hundreds of Christchurch homeowners are facing potential structural uncertainties and financial burdens after the Council alerted them to issues with work completed by a former structural engineer.

Engineering New Zealand recently advised South Island councils that Adrian Collis, a structural engineer previously with Mike Wilton Consulting Limited, made errors in his work and in providing producer statements for building applications under the Building Act 2004.

In July 2023, Mike Wilton Consulting Limited was placed into liquidation, owing $1,111,433.80, including approximately $1,050,000 based on estimated costs for remedial works.

Producer statements, which are professional assessments relied upon by councils to grant building approvals and code compliance certificates, are often submitted by Chartered Professional Engineers (CPEng) to confirm compliance with the Building Code.

In a letter to affected homeowners, Christchurch City Council’s Head of Building Consenting, Steffan Thomas, said, “Concerns over Collis’ work were first raised with South Island councils in March 2023 by Engineering New Zealand.

Following this, Christchurch City Council began scrutinising all approvals involving his work.

“In June 2023, during one of our regular checks, we found Mr Collis’ name no longer appeared in the registry of Chartered Professional Engineers (CPEngs). We had received no advice from Engineering New Zealand, which maintains the registry, that Mr Collis was no longer an accredited CPEng.

“Since that time, we have worked through thousands of consenting-related emails and documents to identify all properties that, according to our records, Mr Collis was involved with in the process of seeking building approvals from us.

“We’re writing to affected property owners because we think it’s important they’re made aware of this matter and of what needs to appear on their Land Information Memorandum (LIM). That way, they have the information they need to investigate further and, if necessary, fix any issues.”

Thomas explained that the council decided to stop relying on any producer statements or designs prepared by Collis due to “continual issues” with his work.

More than 400 Christchurch properties may be affected by this issue.

Are you affected? Email [email protected] 

While these properties may still be compliant with the Building Code, the council recommended that homeowners engage a Chartered Professional Engineer to review their building files and advise on any potential issues.

The council’s letter said, “This may mean that work completed on this property was not compliant with the NZ Building Code and/or building consent at the time the code compliance certificate, or certificate of acceptance or exemption, was issued. The building approval records are available for review on request.”

In May 2022, Mike Wilton was fined and ordered to undergo supervised professional development after providing a consulting report containing misleading statements and misusing another engineer’s signature.

Wilton had been asked to prepare a report regarding driveway repairs for a property his client had sold, which became the subject of a Disputes Tribunal hearing. His report implied he had inspected the driveway in person when he had not.

The same report included the name and signature of a second engineer, misrepresented as having reviewed the report. This engineer was unaware of the report and had not consented to the use of their name or signature.

Wilton admitted to the error but had no explanation for why he did not notify anyone when he discovered it. He was fined $3,500, which the Disciplinary Committee described as “at the higher end of the scale to reflect the seriousness of Mr Wilton’s conduct.” He was also ordered to pay $6,430 in costs, covering half of Engineering New Zealand’s total inquiry expenses.