South Coast Private, located on Crown Street in the former Rydges Hotel, will have 12 new impatient rooms as well as refurbished doctors' rooms and communal areas once the redevelopment is complete.

The newest development plans were submitted to Wollongong City Council and are on public exhibition until April 24.

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The rooms along with one new doctors' consulting suite will be spread across three levels and is expected to be completed, if approved, in May.

South Coast Private executive officer Kim Capp said the proposed redevelopment was an addition to work carried out last year.

"Our Heritage Wing rooms will be converted from doubles to singles, so patients can enjoy their own private accommodation while continuing on their recovery journey with us," she said.

The works include the conversion of one lounge into one single room and refurbishment of two double rooms into four singles.

The internal works proposed seek only to convert existing double bedrooms into single bedrooms to increase the amenity and provide for a higher quality of care for patients, not to create extra beds.

Demolition of the hospital's level four Burelli Street rooms started in December and work included six new patient rooms on Burelli Street, three new patient rooms on Station Street and the conversion of two doctors' rooms into three new consulting suites.

"Throughout construction we've made every endeavour to minimise disruption to our services," Ms Capp said.

"It's been fantastic to have the support of all involved to ensure we can deliver an improved facility that will further enhance the experience of patients, visitors and carers accessing our hospital.

"We're also planning to rejuvenate the hospital's externals to match the quality of our internal works."

South Coast Private provides private inpatient, day patient and outpatient mental health treatment.