For generations of passengers on the main London-Glasgow railway line, one particular stretch of track in Hertfordshire has always inspired wholesome thoughts. For if you stare out of the carriage window as you pass Kings Langley, you see the magnificent art deco edifice that was the Ovaltine factory, which for almost 70 years made the bedtime beverage.

Though the firm behind the drink had been on the site since 1913, its showcase factory was built in 1929, designed and overseen by the head of Ovaltine himself, Sir Harry Hague. It even had its own enormous ballroom.

In 2002, Ovaltine moved its operations back to Switzerland, where it was founded, sparking fears that the unlisted building would be lost. However, worried Ovaltineys can breath a sigh of relief: not only has it been saved, but they can even move in there.

The unlikely saviour is Fairview New Homes, which has come up with the sort of brownfield redevelopment compromise that is increasingly the clever option for a developer. Cynics may argue Fairview’s plan is also a result of lessons learnt after its demolition of another industrial landmark, Nestlé’s old factory in Aylesbury, in Buckinghamshire.

So what does the Fairview vision consist of? Called Grand Union Gardens, it keeps the factory’s 387ft-long, five-storey facade, but nearly everything behind will go, to be replaced with a residential complex in the factory’s original E-shaped footprint by the Grand Union Canal.

The 215 homes in the old factory — now Ovaltine Apartments — have just gone on sale, and the entire scheme of some 370 homes — a third of which will be affordable housing, including a shared ownership scheme through the Sutherland Housing Association — should be finished next year.

So how much is it to live in a rural retreat a mile away from the M25 and a stroll to a station with fast trains (it’s less than 30 minutes to London Euston)? A one-bed flat will cost from £184,950, and a two-bed from £229,950. A mix of different sized homes will be in the 14-acre grounds: a four-bed townhouse will cost from £394,995. Two-bed duplexes and three-bed penthouses will be launched next year. Some factory properties will have balconies and terraces.

The model farms either side of the factory — one supplied the milk, and the other the eggs for the drink — have already been redeveloped. All the new schemes have a hard act to follow in design terms: the inspiration for the dairy farm was the rural idyll built for France’s ill-fated queen Marie Antoinette to play milkmaid.

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