At 122 Roseneath Street in Clifton Hill, opposite a row of pretty weatherboard houses, there’s a stark cinderblock of a building that no one loves. It’s about to be demolished and redeveloped into block of apartments.

But before that happens, it’s hosting the Brutalist Block Party, thrown by Assemble Papers and Open House Melbourne. The building will be home to a produce market, a bar, talks, theatre, parties and craft events: all part of a month-long festival throwing a spotlight on 20th-century architecture’s most controversial development.

Brutalist buildings emerged in the 1950s: hard, grey, functional and hewn from raw concrete. The word “brutalism” comes from the French brut, meaning “raw”. But to many, these buildings look as they sound: brutal.

Architect Graeme Gunn disagrees. In his long career, he designed several Brutalist buildings, including townhouses in Essendon and Kew. He’s a defender of Brutalism, but sees where the contention comes from. “It has a pervasive atmosphere,” Gunn tells me. “Concrete doesn’t have the gaiety of other materials.” To put it lightly.

You’ve seen Brutalist architecture if you’ve ever taken a dip at Harold Holt pool in Glen Iris, or visited the Methodist Ladies College library in Kew. Or strolled past Total Carpark on Russell Street. Or the Plumbers & Gasfitters building on Victoria Parade, which Gunn designed.

So are Brutalist buildings more about functionality than aesthetics?

“No, no, no,” says Gunn. “As an aesthetic it has tremendous potential to be totally different and stimulating.”

“There’s a justified furore around the fact that a lot of these buildings are being torn down,” says Gunn, who argues that at least some of them should be preserved. But perhaps Brutalist buildings will always be under threat simply because they’re not easy on the eye.

“But like all art,” asks Gunn, “Does it have to be pretty?”

The month of events kicked off on Roseneath Street last week with the Brutalist Block Party ping-pong tournament, which took place on bespoke concrete ping-pong tables. The festival continues until its closing party on May 29, which includes live electronica from the Butter Sessions label.

The Brutalist Block Party runs from May 6 until May 29 at 122 Roseneath Street, Clifton Hill.

Find the full program at brutalistblockparty.com.au.

This article was updated on May 12, 2016.