An engineer who forged the signatures of more qualified colleagues to sign off on designs and calculations for hundreds of homes across the country has pleaded guilty to numerous forgery charges in what two of his victims have called the worst building scandal since the leaky homes debacle. 

Jonathan Beau Hall, who goes by Jon or JB, appeared in the Taupō District Court this morning where he pleaded guilty to 113 charges after using two other engineers’ signatures to sign off on producer statements and certificates of design on the houses. 

Engineering New Zealand estimated more than 1000 houses and 42 councils up and down the country were affected by Hall’s forgery, meaning it was likely most of the homes were not compliant with the Building Code. 

NZME understands these properties will have a note added to their LIM reports outlining potential defects with the build unless owners can prove the issues have been rectified. 

One Taupō-based couple who spoke to NZME under the condition of anonymity said they hired Hall’s firm Kodiak Consulting but ended up with more than $100,000 worth of damage through multiple under-engineered steel supports in their new build. 

Hall’s calculations called for the main support beam running the length of the entire roof to be held up by vertical pieces of timber. 

The correct load rating, as the couple discovered, required steel. 

This meant they had to rip out the timber of the mostly-finished house and replace it with steel that would stop the house sustaining extensive damage in an earthquake. 

“We had to strip the insulation out of the walls, rip them apart, cut into everything to fix the damage,” they said. “This whole thing has got to be bigger than leaky homes.” 

The main roof beam that supported this three-storey house was held up with timber rather than steel. Photo / Jeremy Wilkinson 

Hall is an engineering technologist, a qualification that requires a three-year university degree, and needed sign-off on any designs and calculations he worked on by a qualified engineer with a four-year degree. 

He worked with one fully qualified engineer for years before he began forging that engineer’s signature and chartered professional engineer number. 

The engineer, who asked not to be named, told NZME Hall had ruined his reputation in the industry. 

“He would sign off homes without my knowledge… He even used my insurance.” 

The engineer said he was still receiving angry calls from homeowners and developers with threats to sue him for the damage caused. 

“They think it’s me because it’s my company name,” he said. “The stress was so much it gave me a heart attack.” 

The man said he gave statements to police, had since retired, and was planning to leave the country. 

When the man retired Hall began using another engineer’s signature in a similar manner. 

If a property had fraudulent sign-off then its Code Compliance Certificate was potentially void, meaning the home can’t be consented by a council. 

Generation Homes said in a statement it was working with its customers who had been notified their homes might be affected by Hall’s work. 

A Taupō-based property development company, which did not want to be named, told NZME Hall had signed off on roughly 1300 homes and had done the geotechnical reports for many of them, meaning that while the homes might be structurally correct, the ground they were built on might not meet consent standards. 

A fabrication engineer who produced structural beams and supports based on an engineer’s calculations told NZME he’d worked on a number of projects where Hall had done the calculations. 

“A few of these projects have been significantly under-engineered and require significant rework,” he said. 

“It’s a pretty bitter pill to swallow. There’s a lot of people who have been left out of pocket by this. It’s so out the gate it’s not even funny.” 

After Hall entered guilty pleas to 113 charges of forgery Judge Edwin Paul scheduled him for sentencing in Rotorua next year, noting that given the number of victims, additional time would be needed. 

Engineering New Zealand chief executive Dr Richard Templer welcomed Hall’s admission of forgery. 

“Engineering New Zealand first raised this with the police as part of our responsibilities to regulate the engineering profession. 

”It’s very rare to see this behaviour in the profession and I know Mr Hall’s actions have caused a lot of stress for councils and property owners around Aotearoa.” 

Templer said Hall’s plea allowed Engineering New Zealand to continue its disciplinary process regarding him. 

Earlier this year Templar said the scale of the allegations was extremely disappointing. 

Jeremy Wilkinson is an Open Justice reporter based in Manawatū covering courts and justice issues with an interest in tribunals. He has been a journalist for nearly a decade and has worked for NZME since 2022.