He and his husband, hairdresser Martin Corbett, have been renovating a house in Dublin’s south inner city that was built in 1890 and had fallen into dereliction.
Mr Corbett has called for privacy.
In a statement Mr Wallace's family said, "It is with deep sadness and shock that we announce our beloved friend and client, architect, Hugh Wallace, RIAI, passed away suddenly at home last night.
"His passion, creativity and warmth touched colleagues, audiences, and his many, many friends across the country."
RTÉ Director General Kevin Bakhurst said that Wallace's passion for creative design and his advocacy for the wider benefits of good architecture made him "a hugely popular figure with audiences and across the industry," the national broadcaster reported.
"On RTÉ’s hugely popular Home of the Year, Hugh, with his fellow judges, not only opened the door to the most extraordinary homes in Ireland, but he also inspired viewers to engage with the vast possibilities of innovative design," Mr Bakhurst said.
In interviews, Mr Wallace spoke about his experience of alcoholism and his decision to seek help, describing himself as having been given "a second chance at life," RTÉ reported.
“When I was 52 I went to the doctor at the bottom of the barrel and he said ‘you’re an alcoholic’. I was very relieved I wasn’t going to die because now I knew I could stop it,” he told Vickie Maye in The Moments That Made Me podcast from the Irish Examiner.
“I knew what it was and I knew I could get help. I did counselling and went to the Stanhope Centre for rehabilitation."
He also recalled the moment he danced with the legendary Freddie Mercury.
"In 1982 I was in Studio 54 in New York and was lucky enough to have a dance with Freddie Mercury."
He continued to lead an architectural practice alongside his broadcasting work and remained a regular commentator on housing and design.
In an interview with the Irish Examiner last year, he also spoke about the transformative effect of being diagnosed with dyslexia at 18 had on him and the impact of that diagnosis on his career path.
