An “architect’s error” has been blamed for a house being built closer to a neighbouring property than the original plans stated.

The mistake means one of the homes being built on former back gardens in Arkley Drive, High Barnet, will be nearer to the boundary with neighbouring Ravenholt.

Council planning officers did not believe this would cause problems – but the change sparked objections from neighbours and the area’s MP.

Toast Developments won permission in April 2018 to build three homes at High Prospect and land at the rear of Rogate and Saxby, in Arkley Drive.

The following January, the developer was given the go-ahead to build a fourth property on the site.

Work has already begun on the development, which involves knocking down an existing house and building on what were previously the back gardens of three properties.

In October last year, a further application was submitted outlining changes to the scheme, including situating one of the plots 1m away from neighbouring Ravenholt, according to a planning officer’s report, instead of the 2.5m indicated on the original plans.

Planning officers said the change was “not considered to result in any significant levels of adverse impact on the residential amenity of neighbouring occupiers”.

But the council received 20 letters of objection from residents, including one from MP for Chipping Barnet Theresa Villiers.

At a meeting of Chipping Barnet area planning committee on Tuesday (February 11), Cllr David Longstaff (Conservative, High Barnet) called on councillors to reject the amended plans.

Cllr Longstaff said: “The development that has gone on on the site does not accord with what was originally granted.

“The development…was approved on the basis that the impact on residential amenity was considered acceptable, as plot four would be 2.5m, at least, from the boundary, at the closest point to the wall of Ravenholt.

“The constructed house is actually less than 1m from the boundary already.

“As far as I can see, if you agree to this proposal tonight, that means you have already agreed to a breach in the planning controls.”

Cllr Longstaff told the committee that planning permission “should be enforced as was agreed in the original documentation and application”.

But the applicant’s agent, Alan Cox, said: “Planning permission was previously granted for this development in 2019, and the houses have been built, categorically, in the precise location of this approved [permission].”

He explained the northern and southern boundaries of the development had been “incorrectly plotted on the 2018 application”.

Mr Cox continued: “This resulted in a distance of 1.5m between…plot four and side fence with Ravenholt, and not the 1m referred to in the planner’s report.

“This discrepancy is a result of incorrect plotting on national data maps, which clearly indicates a 1.5m gap between Ravenholt and Saxby, fronting Arkley Drive.

“This discrepancy in boundary positions is purely down to us, the architects.”

Under questioning from councillors, he admitted it was an “architects’ error which only came to light when we set out the plot positions”.

Cllr Wendy Prentice (Conservative, High Barnet) said: “If it’s an architect’s mistake, it’s a mistake, and it isn’t what was agreed on planning. It should have been corrected.”

She added: “It’s all very well to say it’s an architect’s mistake, but could we pass any planning that maybe was an architect’s mistake, and just say, ‘oh gosh, sorry’?”

The committee narrowly gave the green light to the amended plans, with three councillors voting in favour, two against and one abstention.