Plans for the £40m overhaul of a mental health hospital with five new wards have been approved by councillors.
The Norfolk and Suffolk Foundation Trust (NSFT) project for Hellesdon Hospital, Norwich, aims to end its "dependence on out-of-area beds".
Project director Peter Burton said 15 extra beds would "have a significant impact" on the numbers treated in a local hospital.
The plans were approved at a meeting of Broadland Council's planning committee.
Planning officer Matthew Rook told councillors the scheme was at the initial stage - meaning design and layout would be agreed later.
The plans, for five, 16-bed non-secure wards, would increase the site from 65 to 80 beds, said the Local Democracy Reporting Service.
Mr Burton said: "The NSFT submitted a bid to the NHS for a Hellesdon ward rebuild in July 2018, which was approved in August 2019."
He said the current site had "narrow and poorly lit corridors", a "lack of quiet space" and "poor access to outside spaces", which resulted in "negative feedback".
He added: "A further driver for the application is the capacity of the whole service and its current dependence on out of area beds and private sector placements."
Mr Burton said the new wards would be a "new and modern therapeutic environment" while "integrated design of wards will make it easier for staff to work together to support recovery".
Conservative councillor John Fisher added: "There is a need to expand units and not send patients out of county - both for expense, convenience and visiting."
The committee unanimously voted in favour of the application.
The NSFT was once dubbed the worst mental health trust in England after failing inspections.