Architecture critic Hugh Pearman described this property as ‘probably the best Modern house in the world’ in 2008. High praise indeed, but Ahm House has earned its stripes…

The Grade II-listed Hertfordshire home – on the market for £3.5m via The Modern House – is the handiwork of Sydney Opera House’s architect Jørn Utzon, who designed it for the chairman of Arup in 1962.

With a striking, copper-edged roof, Ahm is streamlined and slick from the outside. But step indoors and the magic really happens.

The interiors were conceived by Utzon as as series of ‘progressions’: a long open-plan family living room leads onto the dining room and kitchen, while a wall of floor-to-ceiling glass offers views of the surrounding gardens.

Pre-cast concrete beams, exposed brickwork, and timber ceilings all feature across the five-bedroom property, as do Swedish Höganäs floor tiles which create continuity throughout the house.

Pass through the ground floor library, and there’s a second private wing which houses the master bedroom – with doors leading onto the garden – a sauna and dressing room.

In 1972 Arup architect Ulrick Plesner added an extension to the house in keeping with Utzon’s design, bringing it to around 4,500 sq ft.

As an added bonus there’s a skate ramp and treehouse within its ample gardens.

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