The Photographers Gallery in London's West End is to close on 19 September ahead of the redevelopment of its Ramillies Street site.

Plans by architects O'Donnell + Tuomey will see the former Edwardian warehouse turned into a photographic gallery and include the addition of textured acrylic render, Angelim Pedra hard wood and anthracite coloured terrazzo to elements of the existing structure and fabric of the building. The end result will provide three floors of public galleries which will enable the exhibition programme to be expanded; a floor dedicated to learning, offering space for a programme of talks, events and education series and workshops; an improved bookshop and print sales; a passenger lift for public use; and a new cafe at street level.

Opened in 1971 as Britain's first public gallery dedicated to photography, The Photographers Gallery unveiled its redevelopment plans in 2008 with a £8.7m capital campaign. Work on the project is to commence in October and a reduced programme will be operated offsite during the construction period. Working in and around the Soho area, a series of artist-led projects have been scheduled, together with talks and events for visitors of all ages. The gallery will reopen in Autumn 2011, coinciding with its 40th anniversary.