Hampstead Passive House

Sustainability and comfort were at the heart of this renovation and extension of a family home. This project involved retrofitting a semi-detached Victorian villa to meet the rigorous Passivhaus EnerPHit standard, enhancing thermal performance whilst ensuring that the building remains both airtight and breathable.
An existing rear conservatory and ancillary extensions were replaced with a timber-framed addition, seamlessly expanding and improving the circulation to the main family living space. A wildflower green roof enhances biodiversity while providing a natural connection between the upper-floor bedrooms and the garden beyond.
Where possible, the existing building fabric was preserved. New materials and finishes were carefully selected to minimise environmental impact, avoiding petrochemical-based products and incorporating reclaimed or repurposed elements. Even clay soil excavated from the rear garden was mixed into hand-crafted paint, creating a unique, site-specific colour palette.
Photovoltaic panels contribute significantly towards the minimal energy demands of the house and a mechanical ventilation and heat recovery (MVHR) system ensures that there is a continuous supply of fresh and filtered air throughout.
Driven by the clients' passion for sustainability, this project exemplifies what is possible in a conservation area—preserving a home’s historic character whilst dramatically improving energy efficiency and quality of life for the occupiers. The result is a serene, sophisticated family home that sets a new benchmark for sustainable retrofits.