Some real estate agents face investigation for allegedly falsely claiming that houses were designed by architects in an apparent bid to add lustre to their adverts.

The New Zealand Registered Architects Board has laid 23 complaints against agents after discovering a number of adverts they say make misleading claims.

In the adverts, agents tout the houses as being designed by architects, when, in fact, the people who designed them are not registered in New Zealand as architects.

The term architect is restricted to those registered with the NZRAB under the Registered Architects Act 2005.

"Sometimes the advertisements describe the properties for sale as 'architect-designed' and yet an inquiry to the agent reveals that the designer was never an architect," said NZRAB chief executive Paul Jackman.

"Other advertisements name a person as the architect, when the person named is no such thing ... These false references add lustre and market value to the properties being sold, potentially enriching agents and vendors at the buyers' expense.

"People perceive a house as valuable if it has been designed by an architect."

The Herald found a number of properties on Trade Me that agents claimed had been designed by specific architects.

One house in Tauranga was said to be designed by a man who does not appear on the register. He does, however, run a local architecture firm.

The real estate agent said last night she had not realised the man was not a registered architect and would be amending the advert.

"It wasn't done purposefully," she said, adding she had not checked the NZRAB register before listing property. "This issue has only been highlighted to me in the last month or so."

Similarly, another agent's advertisement for an apartment in Auckland listed another man as the architect. According to NZRAB records, the man is not a registered architect.

The agent in that case said the reference to the man was an innocent mistake and not a case of being deceiving or misleading.

"I will be amending the ad if that is the case," he said.

Mr Jackman said he had no criticism of the people named as architects in the listings, but it was unacceptable for agents to label them as such.

"Ninety-five per cent of houses in New Zealand were not designed by architects. Most are designed by architectural designers or draughtsmen. There is a massive difference.

"Under New Zealand law anyone can design a house. But only a registered architect is entitled to use that title."

Real Estate Agents Authority spokesman Dan Ormond said a decision would be made on Friday whether to investigate the 23 complaints.

"Any complaint that the authority receives is referred to a complaint assessment committee. That committee will decide whether to investigate the complaint or not," he said.

Mr Jackman believed the issue was widespread and he had only scratched the surface.

"There will be a myriad complaints."

He welcomed the REAA's decision to review the complaints.

The Real Estate Agents Code of Professional Conduct and Client Care clause 6.4 says: 'A licensee must not mislead a customer or client, nor provide false information, nor withhold information that should by law or fairness be provided to a customer or client.'

"Real estate agents have no excuse. The REAA has repeatedly warned that their advertising must be truthful," said Mr Jackman.

He said any agent could find out instantly whether a person was an architect - current or former - by looking on the NZRAB's website.