Location: London Borough of Lambeth
Sector: Residential, Hotel
Architects: Marks Barfield and 3DW Limited
Structural Engineer: Sinclair Johnson
M&E: Loren Butt Consultancies
Collectively, the UK’s 26 million homes are responsible for more than a quarter of the UK’s emissions (152 MtCO2) of the main greenhouse gas driving climate change. It is relatively simple to build new housing to high environmental standards, the challenge is to bring the existing housing stock up to current standards.
An even greater challenge is to achieve this within one of London’s many conservation areas. London has almost half the total estimated dwellings in Conservation Areas in the UK.
Priory Grove, Stockwell in London overlooks Larkhall Park and sits within the Larkhall Conservation area. It forms the end of a 19th Century terrace and had been a family home for more than 30 years. Built during the 1840s, the building has undergone significant improvements to create a sustainable and generous family home.
Our brief was to extend and refurbish Priory Grove, and to create a home for the 21st Century that is designed to the highest possible environmental standards and low energy use.
The original, single-fronted house has become double-fronted, with an additional floor. A new extension at the back has replaced the former one and is separated from the main house, leaving a light slot between, to bring natural light deep into the plan.
The existing Georgian materials and details were simply replicated, stripping back ornamentation to respectfully carry out the works to the proposed front elevation. Reclaimed Georgian stock bricks were sourced to blend the side extension seamlessly into the original building.The project uses cutting-edge, sustainable technology to bring the 150-year old building into the 21st century. The only external energy supply is sustainably sourced electricity, generated by renewable technologies. A highly insulated envelope (60% better than Building Regs) and passive energy measures of heating and lighting the building have led to minimal energy consumption.
75% of extracted air heat is saved through heat recovery unit, and heating load is boosted with an air source heat pump, which has 20% lower carbon emissions than gas.
The internal temperature is regulated by thermally massive walls which store heat and release energy slowly.
In the summer, low-e glazing reduces unwanted solar heat gain, and the glazed link between the existing house and extension induces a natural stack ventilation effect. Specially designed Portland stone louvres allow secure nighttime ventilation to take advantage of the lower nighttime temperatures.
All timber throughout the house is oak, sourced from European renewable forests. The contemporary extension uses breathable, natural, lime render.