One of Scotland’s most influential architects Gareth Hoskins has died at the age of 48 after suffering a heart attack over the weekend.

It is understood the Hoskins Architects founder died after taking part in a fencing match.

At the peak of his career Hoskins had overseen the growth of his practice, establishing a new German office and recently rebranding the studio to reflect the combined contributions of a growing team.

The practice had only just submitted its proposals for the Scottish National Gallery expansion and was involved with the protracted and ultimately unsuccessful battle to convert Edinburgh’s Royal High School into a hotel.

Hoskins had also been working on a new centre for creativity, production and talent development for the National Theatre of Scotland in Glasgow and a radical revamp of Aberdeen Art Gallery.

Hoskins Architects said this morning: “It is with great sadness that we confirm that Gareth Hoskins OBE, the founder and Managing Director of Hoskins Architects, has died.

“Gareth, who was 48, took ill at an event in Edinburgh on Sunday 3rd January and, despite receiving the best care possible in Edinburgh Royal Infirmary, he passed away on Saturday (9th January).

“Everyone at Hoskins Architects is deeply shocked and saddened by this untimely loss. Our thoughts are with Gareth’s family.”

Chris Coleman-Smith, a co-director of Hoskins Architects, said: “Everyone at Hoskins Architects has lost an exceptional architect, a visionary and a gifted leader, but above all a very good friend. Gareth leaves a huge gap, he was such a special person. We appreciate the very many messages of condolence that have already been received.”

RIAS secretary Neil Baxter described Gareth Hoskins as “one Scotland’s brightest young stars”.

He said: “Gareth was 48 and appeared to be fit and in good health. Sadly, it seems that he had an underlying health problem that had gone undetected.

“He had some very able people around him and his office will take those projects forward, but his creativity and vision will be sorely missed.”

President of the Royal Incorporation, Willie Watt, added: “First and foremost, this is a tragedy for Gareth’s family. Our hearts go out to them. It is also a tremendous loss to architecture in Scotland. Gareth’s prolific and award-winning firm has been among the leading architectural practices in Scotland for nearly two decades. His many prestigious projects for major national cultural organisations includes the 2011 RIAS Andrew Doolan Best Building in Scotland winning reconfiguration of the National Museum of Scotland.

“More recently, his practice has diversified and now operates from its original base in Glasgow and from Berlin. Gareth’s international reputation was growing steadily and he was a tremendous ambassador for Scottish architecture. As all who knew him will also testify, he was a very nice man who, despite his success and growing fame, was invariably modest. As a practitioner and teacher, he excelled. Scottish architecture is much the lesser with his parting.”

There will be a private family funeral and a memorial service for Gareth is planned to be held at a later date.