A Trust fronted by the former British Ambassador to Afghanistan, Sir Sherard Cowper-Coles, will lead an £8 million project to turn Pitzhanger Manor, the “dream house” which was Sir John Soane’s rural refuge, into a major heritage and arts attraction focusing on architecture, craft, decoration and design.

The visionary behind some of London’s most impressive buildings – notably the Bank of England, which he radically rebuilt more than 200 years ago – spent the first ten years of the 19th century at the Manor, where many of the vaulted ceilings, classical detailing and interconnecting rooms he was best known for still stand.

It became the home of the daughters of Britain’s only assassinated Prime Minister, Spencer Perceval, in 1843, and gained an extension during the 1940s, the PM Gallery, which is west London’s largest exhibition space.

The Pitzhanger Manor Trust will now work with Ealing Council on plans to transform the building for the first time since the 1980s.

“This is a vital moment for one of the country’s finest buildings – a place that was very dear to Sir John Soane,” announced Sir Sherard, who said a potential Heritage Lottery Fund award of £3.8 million would help “propel Pitzhanger into a secure future” as a “sophisticated heritage and arts venue”.

“It will continue to serve local audiences and become an intriguing historic destination for lovers of art and architecture from all over London, the UK and beyond,” he added.

“Ealing Council has shown enormous commitment to the project to date and is looking to the Trust for help with fundraising and moving the project forward.”

An Ealing resident who has also represented British authorities in Saudi Arabia and Israel, Sir Cowper-Coles took the Duke of Kent on a tour of the building last December.

His fellow Trust members include BBC Parliament controller Peter Knowles, council leader Julian Bell and, in an alliance illustrating cross-party support for the appeal, the council’s opposition leader David Millican.

Soane dramatically overhaulted the Manor after buying it, keeping his art and antiquities collections there and building mock Roman ruins on land eventually replaced by the gallery, which has frequently hosted site-specific work responding to the look and legacy of the house.

The intricacies of his designs and a number of hidden rooms will be revealed if the bid succeeds. Education spaces and an accompanying learning programme will be created alongside enhanced visitor facilities and landscape work on the grounds of the surrounding Walpole Park.

“Pitzhanger Manor House is a vital and important community asset,” pointed out Councillor Bell.

“The House holds a great deal of local history and stands in a prominent location in central Ealing, so it is no wonder many people regard it with a huge amount of affection.

“Fundraising and public awareness are now key to the success of the restoration project. I hope our efforts will unlock the funding needed for the project.”

A development grant of £275,000 from the Fund last April has given the team encouragement. Full details of the proposals are expected to be announced in the spring, with a further bid at the end of the year ahead of a likely announcement in early 2014.

The Manor will close to the public in mid-2014 if the development goes ahead, reopening in style in spring 2016.

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