Housing minister Christopher Pincher confirmed the move in response to a written question from Labour MP for Mitcham and Morden Siobhain McDonagh.
Pincher said: “We laid regulations before Parliament on 11 November which will introduce a requirement that all homes delivered through permitted development rights meet, at a minimum, the nationally described space standards.
“This requirement will come into effect on 6 April 2021, and will apply to applications for prior approval submitted on or after that date.”
The issue has been a high profile one as the government is keen for permitted developments to form a key plank of its strategy for delivering more new homes.
Earlier this year research conducted for the Ministry of Housing Communities and Local Government (MHCLG) found studio flats measuring just 16m2 in several permitted development (PD) schemes, while natural light was often far more limited.
When pressed on the matter prime minister Boris Johnson failed to fully commit to a minimum size for properties built through permitted developments, but the policy was eventually announced last month.
The measures mean that all new homes in England delivered through PDRs will in the future have to meet the Nationally Described Space Standard.
The space standard begins at 37m² of floorspace for a new one-bed flat with a shower room (39m² with a bathroom).