Less than six per cent of UK architecture firms have signed up to a RIBA climate initiative aimed at achieving net-zero carbon emissions from buildings they design.
Just 230 of the 4,000 Royal Institute of British Architects chartered practices have signed its 2030 Climate Challenge.
Leading practices including Foster + Partners, Zaha Hadid Architects and Grimshaw Architects are among those that have failed to join the initiative.
RIBA chief executive Alan Vallance urged firms to sign up to the "undeniably tough but progressively achievable" challenge.
"Changing the way we practice to combat climate change isn't an option anymore," he told Dezeen. "We need everyone on board to make a difference."
Initiative challenges studios aim for net-zero Launched in October 2019, the voluntary challenge helps architects design buildings with net-zero lifecycle emissions by 2030.
This is in line with the decarbonisation goals of the 2015 Paris Agreement, which aims to limit global warming to 1.5 degrees Celsius above pre-industrial levels, as well as anticipated UK legislation.
Signatories must "attempt to meet the targets on all their new and major refurbishment projects and commit to submitting data on these projects."

RIBA told Dezeen that more practices had signed up recently amid growing awareness of the need to eliminate emissions from buildings, which contribute around 40 per cent of all greenhouse gas emissions.
"We know lots of prac...