This retrofit Passivhaus project (enerPHit) is located in Hampstead and is nearing completion.  London, with its preponderance of tall buildings and concrete surfaces, is particularly susceptible to the urban heat island effect. It is, on average, one to three degrees celsius hotter than the surrounding countryside. Thus one of the challenges we faced was that adhering to Passivhaus is 20% more difficult to achieve in London than elsewhere in the country.

Natural materials where chosen over petro-chemically processed materials.  Many of the finishes were re-purposed from existing materials in the house.  Earth from the rear garden was hand-mixed into the lime plaster to produce a site-specific colour palette.

Photovoltaic panels generate roughly 40% of the building’s energy needs.  The house uses MVHR (mechanical ventilation and heat recovery) to supply and extract filtered air throughout the property.  A lot of effort was made by the construction team to make the house breathable, whilst being air-tight.  This was accomplished with wood-fibre insulation and a lot of specialist tape!