WARLEY may be a former county lunatic asylum, but it is rapidly taking on the airs and graces of an Oxbridge college. Without question, this is one of the most sophisticated and sensitive conversions of a former mental hospital yet undertaken.

I say this with delight and passion. The most agonising sorties I ever made for The Times were for an article on the plight of great Victorian asylums. “These are not the stark forbidding places of our imagination . . . there are enormous landscaped grounds, beautifully planted and maintained,” I wrote in 1995.

When the NHS announced the closure of a hundred of these giant hospitals, many by distinguished architects such as Gilbert Scott, Samuel Daukes and W. H. Crossland, the clear intention was to flatten as many as possible and sell the land for mass housebuilding. Yet when heritage groups took up the cudgels, numerous developers came forward to transform these astonishing buildings into unusual and stylish apartments.

The rescue of Warley Hospital in Brentwood, Essex, has an added romance, because the developer, City & Country, is a family enterprise: a father, a brother, three sons and a cousin. Warley Hospital, now renamed the Galleries, was fast deteriorating when they bought it. Just three years after it closed in 2001, paint was peeling from every wall because of rising damp and leaking roofs. The hospital is a grand, 750ft-long composition in Tudor style and was completed in 1853. Outside there is a wealth of fine red brickwork inset with a trellis pattern in black brick, with exquisite carved stone corbels. Inside there are more remarkable decorative features than I have seen in any other Victorian hospital. Ward after ward has honeycomb terracotta fireproof vaulting. Even the kitchens have arched trussed roofs, and there is an octagonal dome beneath the water tower. All these will soon be ceilings in someone’s proud new home.

The monumental scale of the hospital is broken down by courtyards as large as college quadrangles. These have been beautifully planted with lawns and deep flowerbeds full of colour. The decision not to let people park immediately in front of their doorways has given every home the panache of a grand country house garden. The hospital was built on a corridor plan, with attractive covered walkways that the architects, Kendal and Pope, called galleries – from which the hospital now takes its name.

Phase one is complete with only one three-bedroom apartment remaining, at £485,000. This has a smart modern kitchen and large bay window overlooking its own garden. In Phase two, 16 of the 28 homes have been sold off-plan with prices ranging from £229,000 for a one-bed-room apartment to £530,000 for two bedrooms. When Phase III is complete, 131 new homes will have been created. The grandest apartment will be in the large Gothic Revival chapel. Ian Dieffenthaller, the firm’s lead architect, adds: “One flat contains the clock tower workings and the owner has to wind it once a week. It’s approached up the original 8ft-wide ladder.”

Hurry up and buy, so that City & Country can save another of these magnificent piles.

Details: 01277 202122, www.the-galleries.net

Marcus Binney reviews more of the finest country houses for sale in Britain at: timesonline.co.uk/marcusbinney

FIVE OF THE BEST

St Francis Hospital, Haywards Heath. Former county lunatic asylum, now 300 flats. Savills (01444 445678) is selling a fourbed mews house for £499,950.

Royal Holloway Hospital, Virginia Water, Surrey. Converted by Octagon. Knight Frank (01344 840020) is selling a two-bed ground-floor flat for £375,000.

Friern Barnet, North London. Converted by Comer Homes (020-8361 2424). Two-bed flats cost from £355,000.

Royal Herbert Hospital, Woolwich. Military hospital converted into 228 flats. One-bed flats cost £210,000 (John Payne, 020-8318 1311).

Wyfold Court, Henley-on-Thames, Oxfordshire. Victorian mansion turned mental hospital. Converted by PJ Livesey into 11 luxury apartments. Savills (01491 843012) is selling a three-bed apartment for £995,000. ANDREW RILEY

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