The buildings of Gordon Murray and Alan Dunlop are revered and reviled in equal measure. They have dramatic set-pieces: sweeping overarching roofs, dazzling metallic finishings and over-sized external screens. Yet one of their most understated designs, for a school for the disabled in Dumbreck on the edge of Glasgow’s Bellahouston Park, seems set to push them onto the world stage.

GM+AD, Scotland’s most controversial practice, has been best known — and occasionally dismissed — as a skilled proponent of sexy commercial architecture expressed with a theatrical flourish: the multi-award-winning SAS Radisson hotel; the redevelopment of Glasgow’s Central Station; Bewleys hotel; and the refashioning of a decrepit 1960s office block into the magnificently luminescent aluminium-clad Spectrum House.

Runners-up in the competitions to design the Holyrood parliament and a bridge over the Clyde, it seems the duo’s moment has arrived with this world-class school for children with the gravest sensory, physical and cognitive disabilities. According to Dunlop: “It’s not a school as most people understand it. It’s a place that offers these severely disadvantaged kids the kind of life skills they need to orientate themselves in the world.”

Hugh Pearman, The Sunday Times architecture critic, believes the scope of the project — it will house 52 pupils aged between four and 18 — ensures that Dumbreck will become not only an educational centre of excellence but also a great source of inspiration for architects worldwide.

“It’s a very accomplished piece of work exhibiting subtlety, an inventive use of materials and a good range of thoughtfully rendered facilities,” says Pearman. It looks very assured, very confident and it’s the opposite of institutional in style — it’s almost a domestic project in terms of feel and scale. Because of the age range it caters for and the breadth of disability involved, this school is probably unique anywhere in the world.”

Certainly Glasgow city council, Dumbreck’s sponsor to the tune of £8m, is taking the project seriously. The council is loath to provide definitive comment on the project, as it is set to enter the final stages of its planning application next week, but its leader Charlie Gordon is on record saying: “This is going to be one of the most important projects the council will be undertaking over the next two years.”

The site, a former dairy on the southeast perimeter of Bellahouston Park, is less than straightforward. A conservation area surrounded by 60ft lime trees on two sides and mature beech trees in the centre, the architects decided to let the existing landforms inform their designs. Murray says: “There’s an obvious safety issue with arterial roads and the M77 bordering the site. There’s also the existing community. We’re surrounded by residential development and the people in the stone villas on the north side of the site have been accustomed enjoying an uninterrupted view. Many of those people were concerned that our school would impinge upon their lives but now they’ve seen the plans they’re fully behind it. They were quick to grasp that a world-class school will put their area on the map.”

The school itself has been designed around the gentle sweep of a curving, irregular internal street. There, even the most severely handicapped pupils will be able to know where they are by using visual, sensory and tactile cues. These will come via differing materials, textures and colours, chosen to resonate across the widest spectrum of disabilities. “We’ve used fabric, materials, seating arrangements, even a water feature — anything we could think of to add stimulating points of interest and avoid monotonous forms or sharp angles,” says Dunlop.

Their brief to design the Glasgow Radisson was to push the boundaries for five-star hotel design. Dunlop says: “I think we’ve done something equally groundbreaking here. It’s a timber building specifically designed to integrate perfectly into the landscape. We chose timber specifically with the kids in mind — it’s a tactile material that will age in an interesting way. In terms of the most severely handicapped kids it even has an interesting smell. A zinc roof is a far less dramatic addition than say the aluminium of Spectrum House or the Radisson’s copper screen — those were dramatic theatrical design statements.”

Murray is acutely aware of the professional status of the Dumbreck project. “It reveals the far more complex picture behind our past headlines. It certainly broadens our profile and the remit of things we might do in the future — say, hospitals or large institutional and public projects. It should also confront a few people’s prejudices not only about what we’ve done before but also about our standing as merely Scottish architects. We’d like to think we’ ve come up with a world-class solution that will be received as such. The quirkiness of what we’re known for remains, it’s just this time we’ve expressed it in a wholly different way.”

At another level, it has been an emotionally charged process. “With all the teachers, parents and kids, for this job we’ve got 150 clients. It’s also the sort of project that led us to become architects in the first place. It’s our opportunity to give a bunch of extremely disadvantaged kids the chance of a much better life.”

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