Plans to cover a Grade II-listed building with a large advertising banner will “deface” the historic house and “blot the landscape”, a critic has claimed.

Developers converting former student accommodation at Furnival House in Cholmeley Park into luxury flats want to cover most of the building’s frontage with a banner promoting the sale of the apartments.

Susan Rose, 75, chairman of the Highgate Conservation Area Advisory Committee, said: “It will undoubtedly be a blot on the landscape. I would say it’s defacing it. In the conservation area, it couldn’t really be more inappropriate.

“I think it’s completely out of place,” the Highgate West Hill resident added.

Developers submitted a planning application for a large banner on Camden Council’s website last week. They won planning approval to convert more than 100 student rooms into 15 private flats in 2010, with a swimming pool, gym, spa, basement car park and cycle space in the One Highgate complex.

The advert would read: “Magnificent two and three bedroom apartments and one spectacular penthouse. Secure parking, swimming pool, gym, spa and concierge.”

Michael Hammerson, of the Highgate Society’s Environment Committee, said: “To me, advertising is not totally appropriate in a place like Highgate.

“It’s not something we want to see.”

Haringey Council conservation officer Nairita Chakraborty said she had no objections to the proposal. The Ham&High contacted the scheme’s architects Moxley Architects but they failed to respond.