Since the original application was submitted more houses have been built in the Hornbeam Road development next to the site.
The LDRS said there was only one letter in favour of the original plan which highlighted a growing need for mental health care facilities and the importance of treating people locally.
The healthcare company came back to the council seeking to amend the plans, removing windows from the first floor and some glazing from parts of the building because offices and meeting rooms were no longer part of the proposals.
There were also plans to make minor changes to access and parking.
The changes have been approved by city council planning officers with a number of conditions, and construction must begin within three years.
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