The campaign group Architects for Social Housing is planning to picket this month’s Stirling Prize in protest at the shortlisting of Neo Bankside, the luxury flats designed by Rogers Stirk Harbour & Partners.

It claims the 217 flats are aimed at rich non-resident buyers with price tags far out of the reach of ordinary Southwark residents. It also objects to the way the number of “affordable” flats was negotiated and to the fact they were built off-site.

“This is a very high-profile award, with lots of press attending, so it’s a good chance for us to tell the truth about London’s housing crisis through focusing on an individual building,” wrote organiser Simon Elmer on Facebook.

He said he would be “bellowing through a megaphone” a litany of reasons the flats should never have been built, let alone nominated for a prize for making “the greatest contribution to the evolution of architecture in the past year”.

The list of objections includes developer Native Land’s viability assessments which he said reduced the proportion of “affordable” homes to less than borough policies specify.

“We protest against the nomination of Neo Bankside for building multi-million-pound luxury apartments and penthouses for nom-domiciled tax exiles and foreign investors that will still be empty when 88,000 London children are homeless this winter,” said Elmer.

He helps lead Architects for Social Housing (ASH) which was set up by architect Geraldine Dening earlier this year, partly in response to plans to demolish homes on George Finch’s Cotton Gardens estate in Lambeth.

The group is also planning a protest at Mipim London on October 21 and is looking for an architect to design a temporary pavilion which can be erected outside Olympia to house a street kitchen for the homeless.

“We call on all architects to begin working with London’s communities to help meet their housing needs, rather than accepting their current function as funeral directors of the working class,” said Elmer.

He accused RSHP and the RIBA of “violating” paragraph 5 of ARB’s code of conduct: “To consider the wider impact of your work”.

And he argued that architectural award ceremonies like the Stirling Prize give “cultural legitimacy to the class war being waged through housing in Britain today”.

“We protest against the nomination of Neo Bankside for spending £400 million on 217 luxury apartments when, based on the £177,000 for each of the 13 flats by Níall McLaughlin Architects, they could have built 2,260 Peabody flats,” he added, referring to the housing association flats in Whitechapel which are also on this year’s Stirling Prize shortlist.

Elmer appealed for sympathisers to join the protest outside the RIBA’s headquarters on Portland Place from 5pm so they can address as many guests as possible (“they’ll all be slurping champagne inside by 6pm”).