WINCHESTER architectural practice Huw Thomas Architects has won The Sunday Times British Homes Award 2016 for their redesign and conversion of an old piggery into a home of 5,500 square feet.

Mr Thomas said: “This is the first time we have entered these awards and we were delighted to have been shortlisted, so to win this award is very exciting and satisfying. The owners converted the building themselves, following our designs exactly, and have caught the spirit of the building beautifully.”

Frillinghurst Mill, near Haslemere, Surrey, was formerly a piggery and cattle shelter built in the 1950s.

When Mr Thomas first visited, he realised that this distinctive barrel-vaulted farm building had been designed with skill and care.

“It was very unusual for a farm building to be so well thought out. I thought it was quite exceptional.”

Further research revealed that it had been designed by Walter Shepherd who had worked with an architectural practice in London before becoming a landowner and farmer. It had a deceptively simple design with details including graceful bow lattice trusses.

Convinced of its value, Mr Thomas painted a watercolour to persuade the local planning officers that the premises were worth keeping, and he worked closely with Russell Morris, historic buildings conservation officer with Waverley Council, to convert the building into residential use.

Mr Thomas approached the conversion and design as if it were a listed building with consideration for both its legacy and location.

He added: “As Frillinghurst Mill is located in the Metropolitan Green Belt this could never have been realised without the support of local planning officers. This is an example of what can be achieved when planning officers have the imagination to take that leap of faith into the dark!”

The primary problem with converting this building into a house was light and ventilation. This is a massive and very deep building of more than over 5,000 sq ft without a lot of light. This was resolved by creating a central courtyard and replacing the blocked up cattle shelter wall with a glazed wall, set back to give the appearance of a large opening - reflecting what the building would have been like when it was first built.

The property’s new owners run a groundwork business (Dove Constructions Services Ltd) so they carried out the building work themselves, including sandblasting the original bow beams, supervising and living in a caravan on site. Central to the success of the scheme was the creation of the new zinc roof (by subcontractors GSL) and the owners’ accomplished interior design scheme which enhances the sense of light and space.

Mr Thomas has worked in Winchester years and was instrumental in saving Peninsula Barracks from demolition in the early 1990s.

Of all the architects in Winchester Mr Thomas has probably seen built the most projects including housing schemes in Eastgate Street, North Walls and Little Minster Street.