Lambeth Council has announced plans to spend a million pounds transforming most of the local library space at Herne Hill's Carnegie Library into a commercial gym and then further hundreds of thousands of pounds subsidising its use by Greenwich Leisure Ltd.
Surveys of local residents carried out in 2000 and 2014 disclosed no demand for a gym at the Carnegie, but Lambeth are nevertheless pushing ahead with the plan, with no further consultation.
The library would be closed completely for at least nine months while the work was being done and then reopen without any staff in a fraction of its previous space.
Jeff Doorn, Chair of the Friends of Carnegie Library, said:
"This will destroy our library which is a flourishing hub of the local community and promotes the health and wellbeing of people of all ages and fitness levels, not just the minority who will use a gym. At a time of financial stress Lambeth should be using its limited resources for the public benefit instead of throwing money away and destroying services."