Mark and Candida Diacono had the first project on Grand Designs seeking crowdfunding to support the development when their episode aired back in 2016. 

Grand Designs TV House - farmhouse and cookery school in devon exterior

Image: Clad in larch, the timber-framed house features an amazing green roof, which appears to sway and dip. The original roof was an unusual  American barn shape, which Beth and Andrew were keen to retain. Photo: Paul Ryan-goff

When you first approach Mark and Candida Diacono’s farmhouse and its adjacent cookery school, the pair of swooping, ploughshare-shaped green roofs edged with dazzling aluminium leave no doubt that the two buildings are inextricably linked. This symmetry is exactly what the family set out to achieve when creating a work-life space to house their business, Otter Farm, and a new home.

To find a plot to build on, the Diaconos needed only to look out of their window. They lived in an old end-of-terrace cob house on the edge of two bare fields of grazing land. This came with the house and was originally part of a post-war smallholding that had been split up by the local authority.

Watch the episode: Devon, 2016

Grand Designs TV House - farmhouse and cookery school in devon exterior

Image: Both buildings sit perfectly in their surroundings, taking advantage of the views. Photo: Paul Ryan-goff

A recipe for success

As well as a four-bedroom timber-framed home for themselves and their 11-year-old daughter, Nell, the couple intended to build an adjacent cookery school from which they could run their business, containing a working kitchen, teaching area and office space, as well as an extensive cellar for their produce.

The inspirational farmhouse design is by Orme Architecture. ‘We asked the firm to come up with a few options, but as soon as we saw this one, with a curving roof based on the sweep of a plough, we knew it was right,’ said Mark.

The first problem to be addressed was that the buildings would be outside the limits of planning policy. ‘We needed a design that was engaging enough to tempt the planners to allow us to build, but which would also have low visual impact and integrate with the landscape,’ explained Edd Medlicott, managing director at Orme Architecture.

Cookery school from devon farmhouse project - grand designs tv houses

Image: The spacious cookery school is fitted with British Standard units by Plain English and has bespoke tables by CMJ Carpentry. Photo: Paul Ryan-goff

‘The building feels as though the turf has been peeled up from the earth and it has been slotted beneath. The ploughshare-inspired roofs came about when we started to look at organic shapes – although they’re created from straight joists, the wall plates slope to form an undulating curve.’

There was some doubt as to whether planning permission would be granted. ‘Together with Orme Architecture, we put together a package emphasising that the unique combination of the workspace and home made it a viable business and employment creator,’ says Mark. The local authority planning department at East Devon agreed, after some amendments.

‘They engaged positively with it from the beginning and supported the plans,’ he continues. ‘We did a lot of work on a landscape plan, a traffic plan and measures to mitigate potential visual impacts.’ The proposal had to go to committee before permission was granted.

Grand Designs TV House - farmhouse and cookery school in devon - the kitchen

Image: A contemporary kitchen in slate by Sapphire Spaces includes an island that floats above blue limestone floors by Mandarin Stone. Photo: Paul Ryan-goff

Traditional techniques

Originally, both buildings were to be constructed using a timber frame. ‘It seemed to choose us, suiting the sweeping shape of the roof and our keenness for a highly insulated building, plus it worked with our budget,’ said Mark. ‘But the geotechnical survey dig made it obvious that we were sitting on the perfect material for making cob, which we both love, so we opted for that for the cookery school.’ A deep cellar has retaining blockwork walls, which are then built up with cob to the height of the ground-floor ceiling. Above that is timber frame with a steel frame to support the curved roof.

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Mark and Candida love the juxtaposition of modern construction methods and traditional cob and wood finishes. The house is clad using Siberian larch and the floors are a mix of limestone and oak, with large windows in grey, powder-coated aluminium. There are living roofs on both buildings, with an aluminium edging to each.

Read more:  TV house: Cob house in east Devon

‘The roofing company, A & P Flat Roofing Solutions, was fantastic – the team’s expertise with rubber roofing to make it watertight was invaluable and they integrated that with green-roof technology,’ said Mark. ‘We have sedum on both roofs and since the house roof can take more weight, we’ll plant onions and other low-maintenance edible plants.’ Further eco-measures include shredded, paper-blown insulation in the main house, triple glazing, a thermodynamic heating and water system by Eco Energy Systems, and a rainwater collection system.

Cookery school from devon farmhouse project - grand designs tv houses

Image: The cookery school was completed after the main house. Photo: Paul Ryan-goff

Crowdfunding the budget

Despite selling their old house and taking out a mortgage, there was a shortfall in the budget, which Mark aimed to plug with £60,000 of online crowdfunding.

‘This model of finance is a community-based way of making things happen where both parties get more than the usual exchange,’ said Mark. ‘It worked for us. We not only got the finances we needed, but also attracted people who would invest in our new business, both financially and personally. Looking back, it seems a tall order and it was a lot of money to raise, but I believed that we could reach forward-thinking people who would like the idea.’

Completing the build 

The house was finished and the Diaconos finally moved in during October 2016 to enjoy their new home. A spacious, open-plan downstairs space overlooks their land, while airy bedrooms on the first floor have soaring ceilings.

Grand Designs TV House - farmhouse and cookery school in devon - living room

Image: Mark and Candida kept the living room scheme simple, with a neutral sofa and armchairs. Photo: Paul Ryan-goff

‘We decided to do away with a wall in the fourth bedroom and used a balustrade instead, so that it became a mezzanine overlooking the kitchen, bringing in more light, a greater sweep of the curving roof and a greater sense of space,’ says Mark. The couple found the whole project to be an education, in terms of the skills and creativity brought by the subcontractors and the pleasure in being part of the on-site team.

‘If you get the opportunity to go after a dream, seize it,’ says Mark. ‘However many the disappointments, there are so many pleasures. You have to remember you are the lucky ones to be able to give it a go.’


Location Honiton, Devon
Bedrooms 4 Bathrooms 2
Project started November 2015
Project finished December 2016
Size 250 sqm; cookery school, 320sqm
Build cost £650,000, including fittings
Build cost per SQM £1,700


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