A decade ago, when No 67 Ravelston Dykes Road in Edinburgh was last offered for sale, it was something like a time machine. To step into the house was to be transported back to the 1960s, to an era when it was still believed possible that modern architecture could solve the nation’s ills. The walls were white, the windows were large, and timber was left unpainted so that it might “express its integrity”.

The house’s sale back then caused a great deal of interest. Modernist principles had been desperately unfashionable in the 1970s and 1980s, but by the 1990s designers had begun to talk again about the movement’s standard-bearers — Eames, Le Corbusier, Lubetkin and Mies van der Rohe. And a high-quality example of post-war building such as No 67 caught the attention of the design-literate elite.

In the 10 years since then, the house’s modernist details have gone mainstream. It is hard to find a development of flats that does not reference a few high modernist design ideals — floor-to-ceiling windows, horizontally aligned fenestration, exposed timber, open-plan living and unadorned walls.

This house, however, has a distinction that few properties offered in the past decade can match. In part, that is because it is a house rather than a block of two-bedroom flats thrown up on an urban gap site. Precious few modernist houses were built and this one goes far beyond mere set-dressing.

It was built by the architect Robert Steedman for himself in 1961. Steedman and his architectural partner, James Morris, had become exponents of modernist ideals, but were determined to adapt them for a Scottish setting. During the 1960s and early 1970s, they designed a string of private houses that are among the most original homes ever conceived in this country. All have been listed in the past five years.

No 67 was born out of a commission for a client. Approached by Norman Hunt, a professor at Edinburgh University, Steedman realised he and his client had similar tastes. When Mary Erskine school offered the architect a tract of land large enough for two family homes, he proposed to build a matched pair.

“We have always tried to persuade our clients that the way in which a house responds to its site is everything,” Steedman told The Sunday Times some years ago. “We try to build with style, and that means making the most of the sun, natural protection and whatever views there are. It also means our houses are all different.”

In this one, the three bedrooms are on the ground floor. A sculptural spiral staircase rises up through the building and delivers you into the main living area, which has panoramic views over the long garden.

There is a nook in which to watch television on one side of the 30ft-wide living space, a study behind it and a kitchen next door.

Steedman lived at No 67 for nine years. His former client next door, however, lived there with his wife for more than 40 years. Their home was sold discreetly on the closed market a couple of years ago.

There were changes to the house after Steedman moved on. The flat roof required maintenance, and the heating system — radiant ceiling heat and underfloor electric — was abandoned in favour of a more conventional gas-fired system. The internal arrangement remained much the same, though.

Bimbi and Mike Hargreaves, who have lived there for the past 10 years, have made more changes, however.

“We came here from a large Victorian villa,” says Bimbi. “Our children were still living with us, but they were of an age where we had started to downsize — I am now in my late fifties.”

She did not arrive as a modernist disciple, but the house has made her a convert. “The expanse of light and space is not one that I would give up now. I loved our big house, but there is something about this house that gives you a fantastic feeling.”

The couple have made a more fundamental repair to the flat roof, applying a surface that should last at least 30 years. Once the house had been listed, they also applied for permission to enclose part of the first-floor terrace.

This has enabled the Hargreaves to create a much larger kitchen-dining room with another huge aspect over the garden.

The couple have retained, however, the kitchen’s fabulous east-facing window, with its views over the city and down the Forth to Berwick Law.

The Hargreaves are returning to their roots in Yorkshire, but they will not be giving up big windows or open spaces. They are building a home that will replicate much of the experience of No 67.

Steedman’s house is on the market for offers over £850,000 — quite a jump from the £250,000 for which it was offered in 1998, and a massive advance on the £7,000 that the architect spent on its construction.

Stylistic enthusiasms will, no doubt, move on in the years to come, but this is a house whose design integrity will be winning admirers no matter how the cycle of fashion turns.

Savills, 0131 247 3710

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