AUTHOR JK Rowling has been granted permission to knock down a "perfectly adequate" house she bought for £1 million to make way for a garden extension to her neighbouring mansion.

The Harry Potter writer’s controversial plans brought her green credentials into question, but the move to raze the 1970s house in a plush Edinburgh suburb received no objections from conservation watchdog The Cockburn Association or Historic Scotland.

Rowling’s hope is to restore what was previously the grounds of the B-listed house she and her husband Neil Murray reportedly bought for £2m around 18 months ago.

But the move attracted the attention of others in the cul-de-sac in the conservation area, with one saying after a public meeting that “it is not every day you hear someone seeking approval from their neighbours to flatten a £1m house to make their garden bigger”.

Notice of the decision has been posted online.

Marion Williams, director of the Cockburn Association, said the body did not object to the application as it “goes some way towards restoring an original garden plot”.

“However, we note the loss of a perfectly adequate and functional recently-constructed dwelling from the city’s housing stock and we regret and question the sustainability aspects of this demolition,” she said.

The plan includes a greenhouse and a “garden room” folly with a conical central tower about nine metres high, according to the application.

Solicitors for the couple, who have three children, were asked to detail which buildings were to be demolished after submitting an incomplete application.

John Bury, head of planning at Edinburgh City Council, said: “The proposals enhance the character and appearance of the con-servation area setting of a category B listed building.

“The principle of demolition is, in this instance, acceptable. The land will accommodate a designed formal garden ground, part of which will form new amenity space at the entrance to the remainder of the housing estate.”

The house to be demolished is describe as a modern suburban building that is “not typical” of the traditional townscape.

Rowling, who is worth an estimated £530m, promised to play her part in ending the destruction of the world’s forests at one stage, with publishers told to print all of her books on paper from sustainable forestry projects or on recycled material.