A strictly Orthodox family may be forced to tear down an extension to their Hackney home after a High Court judge rejected their bid to save it.

Matilda Schlesinger argues that the large loft extension at Lynmouth Road, Stamford Hill, is essential to provide enough room for her family, which includes 10 children, ranging in age from two to 18.

But Hackney Council and a planning inspector both rejected the application for the extension — which is already built — on the grounds that it is out of character with the area and the house itself.

Last Thursday, Mrs Schlesinger took her appeal against the inspector’s decision to the High Court, but her case was rejected by the judge, Sir Thayne Forbes.

The inspector, upholding a decision by the London Borough of Hackney, had found that the extension was detrimental to the character of the street.

The extension to the house, in a distinctive terraced area, forms an addition to the home which is “unsympathetic” to the character of the Victorian house, the inspector said in her decision.

Mrs Schlesinger’s brother, Isaac Liebowitz, argued on her behalf in court that the inspector’s decision was wrong and that permission for the development should be granted retrospectively.

He said that in coming to her decision, the inspector had not had the benefit of a report relating to planning for the Jewish community which would have helped her.

The family had been disadvantaged by a lack of resources to put forward the case fully, and the inspector had not taken account of relevant factors, particularly the family’s need for extra space, he said. But, rejecting all of Mr Liebowitz’s arguments, Sir Thayne said he had come to the “firm conclusion” that the case should be dismissed.

“The inspector concluded that there was no evidence that the matter could not be addressed by suitable extensions to the basement or ground floor,” he told the court.

“That was a conclusion she was entitled to draw. The inspector then went on to hold, as she was entitled to, that she did not consider that the personal circumstances of the family outweighed the harm to the character and appearance of the area.”

An enforcement notice, ordering that the extension should be dismantled, has already been issued, but is to be appealed by Mrs Schlesinger in separate proceedings.

Mrs Schlesinger’s brother Isaac said that the judge had allowed the family further time to lodge an appeal.

“We are taking legal advice,” he said. “We are looking at this as a setback but we are determined to fight on.”

The family maintain that there are other loft extensions in the area and that the addition to the building is the only way to solve a shortage of space for large, strictly Orthodox families.

Ita Symons, of the Agudas Israel Housing Association, said: “Unfortunately when people have large families and find themselves in housing need, they often overlook the rules that they should stick to.

“But we are very much dependent on whether a judge views family life as less important than the skyline in some grotty road in Hackney.”