30 October meeting of Islington’s planning sub-committee. Photograph: Islington Citizen.

The conversion of an Islington terraced house has been “rejected out of hand” by councillors who deemed the plans “overdevelopment”.

The three-storey, 19th-century residence at Windsor Road, which is described by council officers as “retaining much of its original appearance and character”, was to be cut into two flats and one studio, with the addition of a basement and roof extension.

However, the plans were met with “fright” by residents, who felt that the proposed basement in the property represented a threat to stability of existing properties, as well as a “serious nuisance” during its excavation.

Resident Anita Graycie said: “Our fundamental objection is that the proposed development will represent an overdevelopment of this site.

“Frankly we’re quite frightened of what might come about.

“Why are these proposals being recommended for approval when the size of the two-bed and studio properties are only just above the minimums as set out in the National Design and Access statements?”

Graycie suggested that the house instead be cut into two flats rather than three, removing the need for a basement.

Cllr Paul Convery (Lab, Caledonian), agreed with neighbours’ concerns, saying: “I think this is overdevelopment. It’s carving three flats out of what is essentially a four-bedroom terraced house.

“I see no justification for the assertion that there’s an exceptional case for having a studio flat, which we would not normally permit.

“The basement habitable room is arguably sub-standard, with no certainty there would be an offsite affordable housing contribution.

“There is a pattern in Islington, tried and tested over several decades, of converting family dwellings like this into two homes. I’m not in favour of splitting up family homes, but needs must sometimes.

“What’s being proposed here is squeezing the max, and pushing standards to a totally unacceptable level, and I would reject this out of hand.

“I’m a little surprised it’s in front of the committee with a recommendation to approve, as I think it fundamentally doesn’t meet our standards.”

The proposals were voted down at a 30 October meeting of Islington’s planning sub-committee.

Unsuccessful applicant Lalita Dabasia said: “Our designs would provide much-needed additional flats in the borough.

“We have engaged a structural engineer to provide a detailed method statement for the construction of the basement.

“The risk of settlement is considered to be small. Bearing in mind we’re only going down one and a half metres, the distraction to the neighbours would be quite small as well.”