When Ali and Rob Lloyd decided to convert a redundant barn, they were determined to re-use and re-purpose wherever possible to create a truly unique barn conversion.

High on a hill close to Peterchurch is a barn conversion like no other, with breathtaking views and undeniable comfort, sitting in 100 acres of farmland which is home to 250 ewes.

But what makes it unique, totally one-of-a-kind, is Ali and Rob Lloyd's dedication to repurposing as much as practically possible of the barn's original timbers and introducing as little that is brand spanking new as they could get away with.

The result is a self-catering property that delights at every turn, with every piece of timber telling its own story. In one of the two downstairs bedrooms, The Duck Room, so named because it was originally Rob's mother's duck house, and before that the pig sty, the timber walls have been cleaned and moved a few feet to serve as the walls of the en suite bathroom.

"It has her china ducks and her favourite chair, too," says Ali. "It was really important for us to put a bit of history into the conversion.

"I have a background in design," Ali explains. She was formerly a wedding dress designer and ran Food From Here, which provided the cafe at Abbey Dore gardens for some time. "We were really keen not to change anything and because it's such a beautiful barn, the layout almost designed itself. We wanted to honour the building and not put in a modern fit.

"Everything we took out, we put back in! And virtually all the timber comes from somewhere on the farm. We didn't want to bring in new oak because it was already full of old oak."

Looking at the photographs of the barn before they started work prompts me to ask if the couple had any idea of the scale of the job they were embarking on.

"We were lucky in some respects in that my brother-in-law and his son, Andrew and Totti Pritchard, are builders," says Ali. "Totti was only 23 when he finished work on the barn.

"We worked alongside them, doing things where we could, but it was the first time we'd done anything like this, and we didn't appreciate just how much work goes into it."

And, as Rob points out, a lot of that work is invisible, like the underfloor heating and the mass of insulation that's gone into making the barn such a welcoming space.

Both Rob and Ali pay tribute to Totti for his ability to interpret their vision for the interior. "It was back of the envelope stuff," says Ali. "I'd come in with an idea and Totti would draw it out on the proverbial back of an envelope and it was always as I'd imagined." Among those ideas was Ali's vision for one of the bedrooms, where a window opening high up (planning for barn conversions always specifies keeping the existing openings unchanged) afforded great views ... if you were nine feet tall. The ingenious solution is an internal balcony and stairs, complete with a comfortable chair from which to take in the glorious views of the surrounding countryside.

Totti also created the impressive staircase, a structure that looks as if it has always been in place. And in a sense it has, as it is made from the 19th century roof purlins. "They had rotted at the ends and could no longer support the roof,but they make a stunning staircase!

"We had struggled with the stairs, because we couldn't find anything suitable," says Rob. "Then Totti took the purlins off the roof and said he'd make them out of that. They're the original roof timbers, which would have been there since the 1800s." The banisters, too, had a former life ... as a manger on the farm.

Rob and Ali's determination to re-use and re-purpose presented the occasional challenge: "All the doors were reclaimed, which means that all the door openings are different sizes!" One of those doors, in the Duck Room, long ago had a hole cut into it, presumably for a cat or dog to come in and out, and the hole remains, with the addition of a sliding cover to keep out draughts!

Even the beds have been made from existing pieces of timber, an old desk cut down to create two striking bedside tables, and, pointing to a cut in one of the beams in a bedroom wall, Rob observes that this is not the first time these timbers have been given another lease of life. Ali also reveals that she spent many evenings whittling toilet roll holders from found pieces of wood: "Not one of them is is the same," she declares.

It wasn't just the roof timbers have have been put to good use in the conversion, the old stone tiles have also been re-purposed, one of them as a splash back in a bathroom.

It's this clever mix of the barn's past with a generous introduction of the reclaimed and the invisible, but very contemporary, technology that makes this property so attractive.

The kitchen, for instance, combines 1950s free-standing cabinets with a fully-functioning contemporary kitchen, and chairs sourced from a Welsh chapel sporting small polished brass memorial plaques. "I did want to put in a reclaimed kitchen, but it just wasn't right," says Ali, with Rob adding that the kitchen they did put in had to be found in a day, and the range cooker brought up to the barn on a tractor.

Gallops in Crickhowell was a great source of reclaimed door furniture and ironmongery, "and they made the radiators". Other happy finds were made at Nigel Ward's sale room in Pontrilas and at Chadwick's in Abergavenny.

As a designer, Ali has also brought her love of colour to the barn, with a paint palette of greens, blues, plums and only the occasional neutral, from Farrow & Ball and Little Greene, and textiles in a wide variety of colours and textures introduced in the form of cushions, throws and loose covers.

Looking back, Rob admits that "We started without considering the scale of it. We just felt lucky that we had got planning permission, and surprised that we had when so many people hadn't. But once we were 12 months into it we began to realise what a big deal it was. It was all we talked about and Jake and Evie would constantly ask if we couldn't find something else to talk about! But once you've started you've go to keep going."

"I could see most of it early on," adds Ali. "We knew it was beautiful and I could always see that it was going to be lovely."

Rob, who grew up at Cothill, his parents having taken on the tenancy in the 1950s and bought the farm in the early 80s, is proud to have given the building a new future. "Farming had changed and the buildings were no longer as useful as they had been. Investment in them had dwindled so it's lovely to know now that they'll stand for another 150 years."