This detached 4-bedroom family home located in the South Downs National Park replaces a bungalow which previously occupied the site and was no longer fit for purpose. The house was designed to Passivhaus principles to make it as energy efficient as possible. The house comprises two floors, with the open-plan kitchen/dining room, utility room, play room and TV room on the ground floor and bedrooms, bathrooms and a home office on the first floor. The design uses a palette of natural and traditional materials such as brickwork and timber. Solar thermal panels mounted on a green roof contribute to the hot water demand and solar PV panels generate a large proportion of the family's electric demand.