Recently, a local family purchased a decommissioned Essex air base intending to turn it into a sustainable farm. The land was dotted with old Nissen huts, still in good condition, and now one of the most significant collections of such buildings in the country, but lacked an actual farm house. Working with architect Cameron Scott of Timberdesign and Rationel Windows and Doors, the family were able to re-purpose one of the air base’s old barracks and add a family living space to create an energy efficient sustainable home. The design of the newly constructed farm house includes a tower that offers panoramic views of the entire property and serves as a reminder of the days when airplanes flew their missions from this very location.

The house is formed by two linear elements, the single storey public space and the storey and a half private space. These two parts of the home are linked via two walkways that in turn form a central courtyard that offer shelter from the East Anglian winds and a safe haven for young children on this working farm. The tower provides 360 degree panoramic views over the surrounding farmland and a linked office provides for the day to day running of the farm.

The primary structure is a Douglas Fir timber frame that is traditionally jointed using mortice and tenon joints for the most part but not following a traditional pattern. The corner braces typically found in traditional timber framing reduce the freedom with which spaces can be laid out, especially with regard to perimeter circulation. These braces were designed out by the use of steel tension rods along with custom designed fixing nodes to resolve the structure allowing the unencumbered layout constructed.

The significant share of the construction fabric is either timber or timber based products. These include: primary structure, secondary structure, insulation, sheathing, floor & roof deck, flooring, insulation, membranes, cladding & joinery. The carbon locked up by this timber building has not been calculated but it is estimated to be significant and quite possibly exceeds that carbon used to construct it.

The efficiency of this family farmhouse has been a priority from the brief onward. Dynamic thermal modelling was used as a design tool in the early stages of development to predict and tune performance. As a result of this work, glazing orientation, roof overhangs and floor construction have all been changed to optimise the thermal comfort and performance of the building. Although naturally ventilated it is estimated that the performance will be close to PassivHaus standards. Post construction monitoring work has already been undertaken with the aim of establishing post occupancy performance over the next few years.

Primary heat is supplied by a ground source heat pump powered by a large 40kWp PV array. Additional energy input comes from passive solar, solar thermal and biomass. Extra care was taken when designing and laying out the heat recovery loops, this appears to be paying off with a coefficient of performance on the heating side averaging a comfortable 4.6.