PROPERTY OF THE MONTH Low-carbon barn conversion
It’s hard to believe that just a couple of years ago, this striking timber- and aluminiumclad contemporary home was a battered old agricultural building in a cattle yard…
Now, Mayfield Barn, near Long Crendon in Buckinghamshire, is a high-spec, four-bedroom, low-carbon home for Lizzy and Patrick Begg, who both work for the National Trust, and their two teenage daughters. In 2019, it received a Federation of Master Builders’ Award for best Low Carbon Project.
Designed by London and Home Counties architectural practice Holland Green, the house not only embodies sustainable building practices, but is also an outstanding example of a Class Q project. This is a form of Permitted Development that allows agricultural buildings to be converted to residential use without planning permission in England and Wales.
The brief for award-winning builder Stuart Barr, of Oxfordshire-based Stuart Barr CDR, was to build a sustainable home with the lowest possible carbon footprint and minimal environmental impact. ‘We used ecofriendly insulation and the house is clad in Thermowood and aluminium, which is sympathetic to the original structure,’ he explains. Much effort was spent making the £530,000 project super-airtight. The Class Q permission didn’t allow for the demolition of the barn’s original concrete-and-steel frame, so close attention had to be paid to addressing the ‘cold bridges’ by taping up joints.
Also, rather than aiming for the unrealistic goal of achieving ultra-high Passivhaus standards in what had originally been a working building, the low-carbon approach focused on re-using materials, which reduces energy output in manufacture, transport and waste, and using the best in eco-technology and bio-efficient waste disposal.
The barn has huge steel-framed tripleglazed windows and doors, underfloor heating, an air-source heat pump and provision for solar panels. The interior has
polished-concrete floors, cabinetry and furniture with ultra-low levels of formaldehyde, and high-grade plywood chosen to mitigate greenhouse gas emissions.
This all chimed with Patrick and Lizzy’s own philosophies as ardent conservationists and supporters of a low-carbon lifestyle; Lizzy is head of environmental practices at the National Trust and Patrick is outdoors and natural resources director. ‘Lizzy and Patrick were my first-ever customers 17 years ago, and we’d stayed in touch,’ says Stuart. ‘They kept horses nearby and were offered the barns by the farmer who previously owned them.’
And he can testify to the project’s success as he lives next door with his family in Mayfield’s twin barn: ‘They asked if I’d like to buy a barn, and that’s how we got started. The Mayfield build was truly collaborative, with everyone pulling together to achieve Patrick and Lizzy’s vision for a sustainable family home.’