At Home: A Modern Rustic Farmhouse

'The whole thing is complete and utter madness,' he says. But there is clearly some method here, too, because what he has achieved is an arrangement of buildings that sits comfortably and naturally within a landscape it was designed to complement.

The architectural conceit of 'newbuild as converted barn' has been particularly well realised inside the house. The entrance hall is painted Pompeian red, a shade favoured by the neoclassical architect Sir John Soane, about whom Ptolemy has written two books. Hung with watercolours and architectural drawings, the space beckons the eye upwards, where the staircase arrives at a gallery landing that overlooks the hall. The landing spans nearly the full width of the building, connecting four bedrooms along the back of the house. More stairs wind their way up to the 'converted loft' and two more bedrooms on the second floor.

The construction is 'honest and traditional', says Ptolemy, pointing to the regular pattern of the Sussex oak beams and the panelled wooden ceiling under the pitched roof. 'It's like a square residential block inserted into a barn-shape construction.' At over 400 square metres, the house is substantial but undeniably homey. 'This isn't an architectural house,' says Ptolemy, explaining simply that 'this is Sussex'. Charlie, who works at Ruston House Interiors in Ticehurst while undertaking a distance-learning course at KLC, says she wanted it to be comfortable rather than grand.

We eat lunch in the kitchen, which is behind the entrance hall. At over 10-metres long, it demands a big table. Made locally from oak, it is, as Charlie says, 'hardy enough for the children and polite enough for us to eat here today. And having a dog has relaxed things a lot'. A relaxed attitude reigns here. Modern pendant lights hang above a large Shaker-style kitchen island, while prints and paintings line the walls - even above the Aga. 'They do get greasy,' Charlie admits with a shrug, although 'the pieces get better the further away from the Aga you go'. At a safe distance are two ancestral portraits from Ptolemy's side. They are in the kitchen because, according to Ptolemy, 'Charlie didn't want them above the sitting room fireplace, which could look a bit stiff.'

The interior was a collaborative project, with Ptolemy giving particular credit to Charlie for her eye for colours and textiles. 'I'd Blu Tack fabrics on the walls and we'd look together,' she recalls. 'It's more enjoyable that way.' Rather thrillingly, when Ptolemy leaves the room, she tells me, 'He's rubbish at putting a room together. He's got ideas, but he gets stuck.'

Between them they have put the rooms together very nicely indeed. The sitting room next to the kitchen has walls hung with an equally eclectic mix of pictures and is pleasingly well endowed with built-in shelving for what is evidently a family of bibliophiles. On the other side of the kitchen, the house connects to a rebuilt version of the converted byre at a right angle, with space for a boot and utility room, a large second sitting room and a spare bedroom. The windows on the inside of this right angle direct views out over the Weald.

At the end of last year, there was talk of the family selling up and moving on - perhaps to somewhere that feels a little less remote. 'It's only seven miles from Tunbridge Wells, but it may as well be 700 miles,' says Ptolemy. A break over Christmas provided some perspective, though. 'We have poured our hearts and souls into this place,' he continues. 'There's a lot to be said for a kitchen facing south-west, and it's wonderful to wake up on Sunday morning and hear birdsong. There is more to be done. It could, in the end, be OK'.

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