Chalk Wall House, Dorchester

 'Chalk Wall House, completed in 2010, was Barefoot Architects first project.  The rammed chalk walls are  constructed of material from the site.  The remainder of the structure is timber, much of it having been first used for shuttering during the chalk ramming process.   A flock of sheep provided wool for insulation.  The extensive roof is planted with sedum.  Solar Thermal panels successfully provide hot water.  Underfloor heating and back up hot water is provided by a wood pellet boiler with a small bulk pellet tank.  Mechanical Heat Recovery and Ventilation is a boon.  Orientation supports Passive Solar Gain; the Thermal Mass of the 18 inch thick (and externally insulated) chalk walls achieves a welcome balance. High roof lights give stack ventilation when needed.

Built in the former vegetable plot of the client's large garden and separated by a mature Beech hedge, the project drew its inspiration and starting point from the local landscape. In view from the site is Maiden Castle - the largest Iron Age Hill fort in Europe, and constructed of huge Chalk banks.To satisfy planning concerns, and minimise visual impact on the existing property and neighbours the house is partially buried into the site. The material excavated to do so was subsequently used to construct thermally massive thick walls against the adjacent Railway lines serving Weymouth to Waterloo, and the neighbours to the North. 

The timber 'formwork' used to construct the chalk walls was entirely re-used to make the floor, roof and external walls of the inner facing courtyard. This sits atop a modular glu-laminated timber frame designed to minimise material waste. The house is super insulated using sheeps' wool, has intensive and extensive green roofs, a biomass boiler, solar thermal water heating panels, a mechanical ventilation heat recovery {MVHR) system and is fully sprinklered to protect against fire.