An Icelandic musician once told me a theory for how his remote northerly country, with its tiny population of 300,000, is able to produce such an inordinate number of interesting artists.

"On a small island like ours," he said, "a photographer can't afford to only take landscapes."

His point was that Icelandic artists tend to muck in, creatively speaking. Whether it's a world-famous pop star trying out an orchestral score or the local brass band leader organising a John Cage happening, "you can't get too precious in a community where everyone knows your family," the musician explained. "Maybe that gives us freedom. Maybe it means we aren't afraid of trying stuff, even if it might not work out."

It's little wonder that Tectonics originated in Iceland. The festival's name is inspired by that great collision of fault lines running a cleft through the country's vast lunar interior. There's also the Ilan Volkov connection: the BBC Scottish Symphony Orchestra's brilliantly gung-ho principal guest conductor and Tectonics founder also happens to be chief conductor of the Iceland Symphony Orchestra.

Then there's the ethos of the thing. Tectonics aims to open up an orchestra and its concert hall to artists and audiences from outside the "classical" sphere. Its three-day programme - which takes over Glasgow's City Halls and Old Fruitmarket this weekend - is a quietly radical, non-hierarchical platform for experimentation and genre recalibration: in other words, there's more than a touch of the Icelandic about it.

Take this year's closing concert, which contains the first-ever orchestral work by a great lone wolf of unbrandable music-making. Richard Youngs is an artist who (to flog the Icelandic metaphor) is willing to explore every potential angle of any potential photograph. Just look at his discography: he has well over 100 releases to his name, each one as capriciously individual as the rest. From the brazen bizarreness of Lake to the raw soulfulness of Sapphie to the jagged austerity of River Through Howling Sky, the only thing that seems to unify his mind-boggling output is its sense of unbridled commitment.

Youngs happily admits that he doesn't have much experience with orchestral music, though as a teenager he did come across Stockhausen, Satie and Xenakis in among his diet of anarco-punk industrialism and mid-period Pink Floyd. "Basically I'd lap up whatever was on the Open University's 6am slot," he tells me over a coffee near his flat in the West End of Glasgow. "This was the late 1970s in small-town Hertfordshire: you had to really hunt for interesting things. If you were young and intense you could commit yourself to the OU's unsociable hours."

Around the age of 15 he acquired his first cassette tape recorder and was off, delving down the highways and byways of experimental music-making. Youngs is perhaps the only person to have been physically removed from an open session at St Albans Folk Club, after having repeated two guitar chords for 15 minutes straight (he can still remember the words of the club's chairman as he was escorted off stage: "I think that did him more good than it did us"). At university he studied philosophy then trained to be a maths teacher, but was dispirited by the unimaginative parameters of both courses and didn't stick to either.

All the while he recorded music with a torrential, boundlessly eclectic zeal. "I've got no attention span whatsoever," he says. "That's why I never stick to one thing. I think that our culture is prejudiced against people who don't stick to one thing. You try out something new and people say 'Come on, you can't be serious'. I am so serious - but at the same time it's all great fun. While I'm doing something I am totally into it, but I can always walk away and watch the Champions League. I'm quite slap-dash that way." Which neatly describes his contribution to Tectonics, too.

It was a midlife crisis and an oversized poster that did it. A couple of years ago, Youngs was experiencing what he calls "an illogical nostalgia" for the music of his youth - in particular the short, sharp, hyper-charged rhythm known as D-beat.

"I was rediscovering the joys of bands such as Discharge. When I was a kid, there was a guy in my town who had the highest spiked hair I'd ever seen and the entire lyrics of Discharge's Mania For Conquest on the back of his leather jacket. He was a bit older than me and I thought he was very impressive."

Youngs never achieved the hairstyle ("I didn't know the requisite technology; I was quite naive") but the allure of D-beat evidently lodged and in 2013 he recorded a Discharge-inspired album called Barbed Wire Explosion In The Kingdom Of Atlantis.

Soon after, he was walking down Byres Road and saw a BBC SSO poster featuring Ilan Volkov. "I thought, 'What about an orchestral version of D-beat?' The idea was interesting, hilarious and absurd. I thought, 'If anyone could make it happen, Ilan could.'" Volkov responded within 10 minutes of Youngs sending the email. "He said the idea was perfect for this festival called Tectonics. It was a huge leap of faith."

For Youngs, the prospect of writing a fully-scored, BBC-commissioned work for symphony orchestra was as left-field as anything he'd done. He borrowed library books on orchestration and set to work, writing out the D-beat rhythm for symphonic percussion section and devising horn lines out of D-beat band names (Disobey and Discontent spelled in repeated patterns across the musical stave). The viola part consists of screaming guitar feedback transcribed into notation.

About 12 minutes into the piece, Youngs himself takes a guitar solo. "I just hit it," he says, "like a sonic equivalent of brutalist architecture." And that's the piece: 15 minutes of D-beat rhythms, howling feedback, encoded band names and an almighty explosion.

Volkov will conduct the premiere on Sunday in the Old Fruitmarket, with the BBC SSO strings scattered among the crowd, the brass on the balcony and the percussion on stage. Youngs doesn't seem concerned about whether it all syncs up.

"The piece is called Past Fragments Of Distant Confrontation," he points out. "It isn't meant to sound perfect."

Tectonics runs in Glasgow from Friday to Sunday

www.tectonicsfestival.com/glasgow