"I use an electric wheelchair to get around and I wanted to show society that even though you have a disability like cerebral palsy that you can set yourself these outrageous goals and conquer them," he said.
"So I thought why not climb towers?"
Mr Milroy tackled the Sky Tower's 1029 steps last year in just 30 minutes.
"I think everyone was shocked at how fast I went up it," he said.
He's also climbed the 297m Eureka Tower in Melbourne, and hopes to take on higher climbs in Australia and the US in future.
"I do it because I enjoy the challenge and I enjoy teaching people about cerebral palsy," he said.
But his next challenge will be cycling around the country to take his message to more New Zealanders.
"I'm going to be on the road for about a month, starting probably in February."
He posts updates about his training and upcoming climbs on the 'Jordan's climb for awareness' Facebook page, which has more than 5000 'likes'.
Mr Milroy, who is studying towards a communications degree, was a top 10 finalist in the Young New Zealander of the Year 2013, and was nominated by the Cerebral Palsy Society as its Person of the Year in 2012.
World Cerebral Palsy Day today marks the start of a month of awareness about cerebral palsy in New Zealand.
Chiefs Coach Wayne Smith is also an ambassador for the event. His son Josh, 30, was born with cerebral palsy, and is completing the last paper for his degree at the University of Canterbury.
"Things we take for granted are different for people with cerebral palsy - just don't lower your expectations of them," Mr Smith said.
"They have incredible capacity and ability."
The Cerebral Palsy Society in New Zealand provides resources, grants, information and practical support to thousands of people living with cerebral palsy.
