A couple who designed their own barn conversion over 20 years ago have put it up for sale for £850,000 - and now say they are looking ahead to the next challenge.

You don’t have to speak to Sally and Stephen for long to realise their passion for property.

They started work on St Mary’s Retreat in Cranworth around 20 years ago, after living in – and converting – two other properties in the same village.

They’ve worked their way south, Stephen says, from an annex to a three-storey barn and now to St Mary’s Retreat, a four-bedroom split-level barn of mainly brick and flint, which offers fantastic views over open fields to the south.

Now they say they want another challenge so have put it on the market with Strutt & Parker.

The conversion has been a passion project and a collaboration involving lots of hard work. “We didn’t do it ourselves,” Stephen says. “It is by no means a self-build, but we did design it. Of course we used architects and surveyors and builders to do the work, but between us we’ve designed all the properties we have lived in in Cranworth.”

Stephen says his best friend, Rodney Palmer, was a key influence on the architectural side of St Mary’s Retreat.

“Much of the time it’s been quite hard, honestly, because I was working in London and I’d come home in the evening and the first thing I’d do is see what the builders had done during the day.

“Sal had a harder job than me, without any doubt – she was bringing up two small children and there is no doubt that’s a lot harder than me nipping to London and coming back and looking at the building work. You perhaps don’t appreciate that until you get older.”

Throughout the design and then the build, they wanted their home to be different. When they bought it, it was a single-storey cart shed. It had six or seven open bays, a closed-in garage and from the front, Stephen says it looked very much like a bungalow. “Our architect wanted to keep it as a bungalow,” he says, “but we decided to do something different.”

They dug four feet into the ground at either end, which helped them create the space for the mezzanine floors. Their previous work on the three-storey barn, up the road, had given them the confidence to do more with the space.

“I guess some of it came from the earlier conversion of the bigger barn,” says Stephen. “We had introduced a third floor, spiral staircases, galleries, all sorts of stuff. Those things are pretty commonplace now, but they weren’t 20-30 years ago.”

Being open-plan was also important, he says, as well as its points of interest. “It needed to have vistas. In other words, wherever you look there’s something interesting. I mean there’s not much point doing it, to a barn, if you’re not going to make it interesting, is there? You might as well buy an ordinary house.”

St Mary’s Retreat is far from ordinary – even for a barn conversion.

It’s much bigger than it looks, with split-level living spaces and family-sized rooms and there’s an openness to it that is immediately welcoming.

From the well-fitted kitchen you can get to pretty much any room in the house. “You can just go straight into the lounge, straight into the dining room, and it’s a really nice entertaining area,” says Sally. “I think that’s what I like the most about it, and probably what we will find hardest actually to match.”

The lounge is sunken into the ground and has a “pretty impressive” fireplace, says Stephen. “We only ever put it on for comfort,” he says. “We never needed it for the heating because the heating system is really good, but the hearth part of it is about three feet off the ground and it’s got a great hood that takes the smoke outside.”

The bedroom wing comprises the master bedroom with its en suite bathroom and three further bedrooms which are served by a good-sized family bathroom. Each of the bedrooms enjoy views over the front or rear south-facing gardens, which are mainly laid to lawn with intermittent hedging and well-established trees.

Elsewhere the gardens include a well-positioned summer house, wired for electricity, and a patio and pagoda. A further terrace, to the side, can be accessed from the living room.

The wider location is special, too. It’s within “spitting distance” of St Mary’s church, Stephen says – hence the property’s name – and although it’s “tucked away”, it’s still within 100-200 yards of the “very friendly village.” For a wider range of amenities, there’s Hingham, 3.5 miles away, or Wymondham, which is 10.

Sally and Stephen have clearly loved life in their home and are honest about the things they will miss. But they’re also excited for the future. “The girls are forging their own lives and our son at 43 is well-settled, so we thought ‘well, let us do something else, let us enjoy another challenge’,” says Stephen. “We’re up for it.”

They will definitely stay in Norfolk, they say, and maybe even move closer to Norwich. “I think we still want lots of space but I think we’d probably like a place to sort of put our own stamp on again,” says Sally. “Just to make life interesting, really.”

Contact Will Mullan at Strutt & Parker on 01603 883605 or 07471 216099 for details.

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