A storm has erupted over a two-storey house being built in the back garden of a Crouch End home – with neighbours calling for the work to be stopped in its tracks.

Developer Docklock Ltd has started work on the two-bedroom house, which is at the back of a gothic-style mansion in Crescent Road.

Yet it does not yet have planning permission – and a planning application was not submitted to Haringey Council until September 7.

The developer claims the work done so far is only “foundations and underpinning” to stop the building there already - a derelict one-storey apartment - from falling down.

But neighbours insist no work at all should have started without planning permission – and claim the existing building was no more than an outhouse.

Tec Fawcett, secretary of CASCH Residents’ Association, which represents Crescent Road and the surrounding streets, said: “It’s absolutely awful.

“Apart from all the noise, it’s spoiling an area which was a nice nature reserve. It was like a green oasis there and it’s an area that bats use.”

Cllr David Winskill, the Liberal Democrat member for Crouch End, who is backing the residents, said: “This is a conservation area and the planning process must be observed.”

In its planning application, Docklock Ltd admitted that work started on August 12.

But it stated: “The original building was in a poor state of repair with many of the walls becoming dangerous structures.

“Therefore, these structures were carefully replaced with new foundations and underpinnings so that the walls could be repaired and made safe.”

Docklock added that the proposal was merely to “bring back into use” the existing apartment, which council tax and Royal Mail records prove was once used as a home.

The house is being built in the back garden of a gothic-style mansion which was once a hostel operated by Haringey Council but has since been converted into nine flats.

Haringey Council issued a notice telling workmen to stop building on September 10 while it considers whether to give the go-ahead.

A council spokeswoman said: “Action was taken after it was brought to our attention that a two-storey structure had been built in the rear garden, which exceeded the size of a former building it was intended to replace.

“The developers have submitted a retrospective planning application, which is under consideration by the council.”

The developer was unavailable for comment.