Macintosh, now retired, was selected in celebration of her work in public architecture and advocation for the use of buildings as a tool for social justice since the 1960s.
"I am absolutely thrilled by this news, not least because I knew Jane Drew personally and occasionally we shared a platform in schools of architecture," Macintosh told the award's organisers.
"Our value systems chimed as we discovered when we overlapped on RIBA council."
Macintosh was born in 1937 and raised in Edinburgh, which was the same city in which studied to become an architect – graduating from the Edinburgh School of Art in 1961.
She began her career in the industry working on the early designs for Denys Lasdun's National Theatre in London, before going on to design public buildings for local authorities in London from 1965 and onwards.
It was during this time, at the age of 26, that she conceived Dawson's Heights – a listed social housing estate in London. The scheme is widely regarded as her most significant project and has seen her dubbed one of the "unsung architects of social housing".
Macintosh continued to make her name in the public building sector in the years that followed, working on projects ranging from sheltered housing to schools and fire services. Many of these were completed in collaboration with her life and work partner, architect George Finch.
Last year, women's collective Part W said her "work has so often led the way – across public housing design, social theory, education, women's rights and tenants' rights."
This week, the W awards also announced that novelist and educator Lesley Lokko was the recipient of this year's Ada Louise Huxtable Prize. The award, named after American architecture critic Ada Louise Huxtable, honours those who have worked and contributed to the wider architectural industry.
It follows the reveal of this year's shortlists for the W awards' MJ Long prize, an award for excellence in practice, and the Moira Gemmill Prize for emerging architects.
The nominees for the MJ Long prize include Ingrid Petit of Feilden Fowles for her work on The Fratry, alongside Alice Brownfield of Peter Barber Architects, Hannah Anderson of Walters & Cohen and Wright & Wright's Naila Yousuf.
The six co-founders of Spanish studio Lacol – Ana Clemente, Laura Lluch, Núria Vila, Eulàlia Daví, Ariadna Artigas, and Cristina Gamboa – have also been shorlisted.
Portrait is by Ivan Jones.