Paul Carter sits on the shadow board of the Ebbsfleet Development Corporation that is responsible for driving the creation of a new garden city in north Kent.
In March’s budget, the Treasury said that a dedicated urban development corporation (UDC) would be formed to build 15,000 homes in Ebbsfleet as part of a new garden city.
Speaking at a conference on Friday on designing a contemporary garden city, Carter referred to the opening of new homes last week by planning and housing minister Brandon Lewis at the Caste Hill development in Ebbsfleet’s Eastern Quarry.
Carter said: "Do they, let’s be honest, fit the bill for a contemporary, modern garden city here in this location? I think not.
"The housebuilders have built what they think the market wants but clearly not what we genuinely would like to see."
Carter, a Conservative, said the development was "not in tune" with landowner and developer Land Securities’ "original vision" for Eastern Quarry "with real quality design and spatial planning in a sensible way".
He added: "We all know the UDC will be tasked with making sure we get good design at pace and in volume. That will be an enormous challenge."
Carter went on to describe the new homes as "boxes" and said housebuilders would get a higher premium if their products had a higher-quality design.
Land Securities, which owns the site, said it did not wish to comment on Carter’s comments.
Caste Hill is a 150-home development created by Ward Homes which is owned by housebuilder Barratt.
In the March budget announcement, the government said that up to £200 million of infrastructure funding would be made available to kick start development.
Carter said that realising the vision for Ebbsfleet "will need the government to get its cheque book out" to support the necessary infrastructure around health, educational and transport.
He added that the UDC chairman Michael Cassidy was "putting pressure" on the government to get Crossrail extended to Ebbsfleet.
Also speaking at the conference, in Ebbsfleet and hosted by Kent Design, was David Lock, founder of masterplanning consultancy David Lock Associates, who said it was vital for the UDC to focus on quality.
The former chief planning advisor to the Department of the Environment warned that a focus on housing numbers rather than place-making would be a "wasted opportunity" for Ebbsfleet.
He said it was now time for "action" in Ebbsfleet, not for further plans or visions.
Lock further questioned whether the powers of the UDC were sufficient for the task, in contrast to a development corporation set up by the New Towns Act, which he described as "an excellent piece of legislation".
The latter, Lock said, operates for up to 50 years and has a brief to do "all that is necessary" to build a town. A UDC, however, is a "short-life organisation", he said, whose finance is provided by central government and cannot borrow money or build houses.
In August, the government announced Cassidy’s appointment and consulted on the scope of the body’s powers.