The Threshold Centre is unique, a pioneering cohousing community and sustainability education centre; a model of a greener, more affordable and more neighbourly way of life. Bruges Tozer Partnership worked closely with the cohousing group to redevelop a farmhouse, outbuildings and barns around a shared green space. It provides 14 dwellings of mixed tenure in conjunction with East Dorset Housing Association, guest accommodation, educational facilities, car pool, market garden, communal laundry and many other shared amenities.
The majority of the buildings were retained with minimum alteration to their appearance. Sette Barn and Timber Barn required extensive structural alteration and extension to add new floors and modified roof profiles. These were clad in natural weathering local larch with reused bricks and tiles from the original buildings. The result is a mellow, harmonious composition of old and new.
Despite inadequate foundations and considerable movement, the original external brick walls of Sette Barn were retained for planning reasons with existing openings adjusted and insulated internally. Party walls were inserted to take the load of new upper floors, walls and roof using a composite timber frame on a glulam primary structure, tying the existing walls in place.
The Centre is designed to encourage a more sustainable lifestyle by addressing the primary causes of CO2 emissions: food, transport, heating and domestic energy demand.
A productive community market garden and locally sourced food supply sustains the community. Car pooling, on-site work and social activities reduce the need for transport and car use.
An Ecohomes Excellent rating is achieved through:
Materials: Careful choices of materials with low environmental impact either salvaged from site or local and responsibly sourced materials through a certified chain of custody.
Water conservation: Less than 80 litres per person per day achieved with:
Shower outlets incorporate air entrained restrictors, a small number of low capacity baths, flow restrictors on all taps, no dishwasher or washing machines within units. Clothes washing use 2 ‘A’ rated communal machines running on harvested rainwater from a 1,340 litre tank. WCs are dual flush 4/ 2.6 litres capacity.
External water saving measures: Surface water run-off from roofs is stored in tanks for rainwater harvesting providing sufficient reserve capacity for the gardens, giving a combined storage capacity of 7,200 litres.
Energy conservation: Super-insulation and a comprehensive renewable energy strategy. Shared facilities, guest bedrooms and function rooms allow for reduced individual dwelling size and consequent heating demand.
Heating & hot water: District heating and hot water scheme for all dwellings and the Farmhouse provide for all heating and hot water demand from a central packaged wood chip and pellet boiler with a capacity of 100kW.
Electricity: Low energy lighting throughout. All lighting, pumps and fan loads offset by a grid connected 4.42kWp Photovoltaic array.