Overlooking the Coquet estuary in Northumberland, this bespoke timber-built Certified Passivhaus has been carefully designed by MawsonKerr Architects to be kind to the environment, low cost to run and comfortable to live in.
LocationWarkworth
Gross Internal Floor Area204 m²
ArchitectMawsonKerr Architects
Project TypePrivate
Building TypeHouse
Structural EngineerJCC Consulting
Main ContractorTrue North Construction
Joinery ContractorTrue North Construction
Wood SupplierRusswood | Timber Frame: PYC Frame
Product InfoCassettes: OSB, SMARTPLY PROPASSIV, MEDITE VENT (Ireland). Internal joinery and floor: Engineered oak; birch-faced plywood. External timber cladding: Larch. Window frames: Spruce.
Timber SpeciesSpruce; Oak; Birch plywood; Larch
Timber ElementsTimber frame; Window frames; Cladding; Joinery
Upfront carbon emissions (A1-A5)310 kgCO2e/m²
Stored biogenic carbon255 kgCO2e/m²
Operational energy (B6)19.9 kWh/m²/yr
Airtightness at 50pa0.17 m³/hr/m²
Design life100 years




Located at the edge of a designated Area of Outstanding Natural Beauty, the layout of Godwit House maximises views and daylight whilst respecting visual impact on neighbouring homes.
A refined minimalist barn-like form combines influence from local agricultural structures with crisp detailing to create a contemporary dwelling. High quality materials that reflect the visual character of the local area were specified, with larch vertical cladding and Northumberland sandstone used for the exterior of the building.
Sustainability and energy efficiency were key criteria for the project and the house exceeds the RIBA 2030 Climate Challenge targets and is a Certified Passivhaus.
It was important to both architect and client to use natural and low embodied carbon structural materials. This led to the use of MMC factory-built timber cassettes, filled with wood fibre insulation, for the superstructure. Along with the careful detailing and modelling of junctions and the skilled craftsmanship of the contractors, this approach enabled the execution of a super-insulated, airtight and breathable frame.
Electricity is generated by PVs on the roof, which run the ground source heat pump and the EV charger. The project also helps to increase local biodiversity, with a green roof, rainwater harvesting and two ponds.