The public will only be able to visit an historic Second World War bunker under Friern Barnet Town Hall on 12 days of the year, under plans to convert the town hall into flats.

Councillors voted through an amended planning application from Barratt Homes on Thursday last week (May 20) that will see the Grade II-listed town hall, in Friern Barnet Lane, turned into 33 luxury flats. Two two-storey blocks will also be built to the back of the building, providing 11 flats. The nearby former fire station, which is not listed, will also be converted into five flats.

Stewart Murray, the council's head of planning, said: "We consider that this is the best acceptable solution to protect the building's historic status and give the public access to it. The developer will fund the restoration and give new life to the building for the future."

He added that English Heritage, the agency set up to protect sites of historic interest, had signalled that it approved of the revised application. But some councillors and residents said 12 days a year for the community to visit an important local landmark was just not enough.

The town hall was built in 1939 with an air-raid shelter basement incorporated into the plans. A group of local history enthusiasts had hoped to turn the bunker into a museum looking how people lived in the Blitz.

But Dr Oliver Natelson, of Hollickwood Avenue, said last week's decision had consigned the museum idea to the dustbin of history' because no outside organisation would provide funds for such a small number of opening days.

"Two thousand local schoolchildren will be denied access to a good learning environment about the Second World War amid the the wonderful wartime basement relics of Friern Barnet Town Hall," he said.

Under the plans, a senior citizens' day centre on the site will move to Friary House in Friary Park, which some centre users say is more difficult to get to.