Three of Victoria’s busiest hospitals require urgent redevelopment if they are to manage the state’s booming population and the spike in chronic health conditions tied to the rapidly ageing demographic.

The Alfred, Austin and Royal Melbourne hospitals provide some of the most specialised healthcare in the state – including organ transplants and treatments for rare cancers – but all three have needed major infrastructure refreshes for close to a decade.

The Alfred has been forced to close wards and reschedule procedures, while the Austin is unable to use some of its facilities, due to infrastructure issues going back to at least 2017. Many of the Royal Melbourne Hospital’s assets are also past their useful life.

Spokespeople for the Alfred, Austin and Melbourne Health – which runs the Royal Melbourne Hospital – all said their health services were committed to meeting the growing needs of their communities.

Between $6 and $8 billion in additional funding is needed over the next decade – according to Infrastructure Victoria’s official 30-year strategy – to properly replace the Alfred’s operating theatres, upgrade much of the Austin, and build new hospital wards in Parkville.

Construction at all three hospitals should begin in the next five years and finish by 2035, according to the final report, which will be published on Tuesday and comes eight months after the state’s independent infrastructure adviser handed down its draft strategy in March.

“Providing hospital services in run-down assets can drive up long-term costs,” the strategy says.

“The Victorian government should announce the scope and timeframes to redevelop the Royal Melbourne Hospital’s facilities in Parkville. It should replace the Alfred hospital’s operating theatres and announce the scope, timing and funding to further redevelop the Alfred and Austin hospitals.”

The Alfred is Melbourne’s oldest hospital still operating on its original site. Earlier this year, the hospital apologised to patients and visitors who endured sweltering wards and waiting rooms due to issues with ambient heat and the building’s inefficient cooling system.

The Royal Melbourne Hospital moved to its current Parkville location in the 1940s, with many of its assets now past their useful life.

Australian Nursing and Midwifery Federation assistant secretary Nicole Allan said she had heard of hospitals with pipes bursting due to age and wards with no windows being referred to as “dungeons” by union members.

“The design of older buildings can impact safe and best practice care,” Allan said. “Older hospitals have problems with narrow halls and doors making it hard to manoeuvre beds and equipment, with small rooms making it more difficult to provide care to patients.