Tributes have been paid to one of Scotland's great post-war architects, Isi Metzstein, who has died after a long illness.

Working for the Glasgow firm of Gillespie, Kidd & Coia with his partner Andy MacMillan, Mr Metzstein, who died aged 83, designed some of the most notable modernist buildings in the country, including numerous churches as well as the world-famous St Peter's Seminary at Cardross.

Last night a "very sad" Mr MacMillan said he had been "architectural pals" and friends with Mr Metzstein since September 1945, when they met at architecture school.

"People have asked what the legacy will be, I think it really was the way he was a teacher of young architects, and also young people who came and visited our offices – and they are architects practising today, that is the legacy," he said.

"We knew it was coming, but it is a sad day I must admit. He was a witty man, he was well loved and highly respected. He will be missed."

The Archdiocese of Glasgow said Mr Metzstein's designs for churches "transformed the understanding of generations of ordinary worshippers of what a church should and could look like."

Mr Metzstein, born in Berlin in 1928, won the Royal Scottish Academy Gold Medal for Architecture in 1975 and was an honorary fellow of the Royal Institute of British Architects, the Royal Incorporation of Architects in Scotland and was an influential teacher and professor at Glasgow School of Art.

Mr Metzstein's family moved to Scotland when he was 11, and aged 18 he was hired by Gillespie, Kidd & Coia.

With Mr MacMillan, he was one of the key figures in the development of modern architectural design in Scotland, including St Peter's Seminary, which for many years lay in ruins but is now finally to be redeveloped by NVA, the Glasgow-based arts company.

Sholto Humphries, president of the Royal Incorporation of Architects in Scotland, said: "There is no question that the double act of Isi Metzstein and Andy MacMillan were the greatest architects of the latter half of the 20th century. Their legacy in Cumbernauld, in Glasgow, throughout Scotland and much further afield is an architectural achievement of which we can all be very, very proud.

"Isi Metzstein was a man of great humour, extraordinary wit and sometimes acerbic turn of phrase.

"His teaching methods were unconventional but the students he taught are now some of the best architects in Europe."

Professor Seona Reid, director of the Glasgow School of Art, said: "Gillespie Kidd & Coia's work under the visionary leadership of Isi Metzstein and Andy MacMillan represents one of the most significant and influential contributions to post-war British architecture.

"Isi Metzstein was a great architect, a remarkable teacher, and above all a very special person who will be greatly missed."

A spokesman for the Archdiocese of Glasgow said: "Isi Metzstein had a huge influence in the day-to-day lives of Catholics in the west of Scotland over the last 60 years.

"His innovative work transformed – not without a certain degree of consternation on the part of the occasional mystified parishioner – the understanding of generations of ordinary worshippers of what a church should and could look like. No less than 11 of the firm's commissions within the territory of the Archdiocese of Glasgow alone are now listed for their architectural merit, often being the only building of real artistic significance in the area."

Angela Brady, president of the Royal Institute of British Architects, said: "Isi Metzstein will be remembered fondly both as a great architect and educator who was known to be outspoken and had great courage and colour."

Angus Farquhar, creative director of NVA, said: "St Peter's Seminary is one of Isi Metzstein's great legacies to the world, I hope we can do his courageous creative vision justice and help it find a new direction for the 21st century."