Dorsal House is a new build, 6 bedroom family house on the edge of Epping Forest in East London that is targeting Passivhaus Plus Certification.

The brief was for a Passivhaus private house which would sit comfortably in its surroundings while maintaining a distinct quality. The local buildings are a mix of Victorian brick large detached houses and more contemporary infill developments.

The low energy standard requires careful attention to be paid to the first principles of the building. Orientation, glazed openings and the airtight details of the construction all contribute to the extremely low energy demand to run the building through its life. Renewable energy is incorporated with solar panels and an air source heat pump, and an MVHR system prevents energy from being wasted through mechanical ventilation.

The massing of the house is driven by the tight urban site, which has never been previously developed. Neighbouring houses have enjoyed the light passing across the empty site, and so the new house curves around the passage of light, leaning out of the way of adjacent windows.

Contemporary digital technology has been essential for the design and development of the building, from the setting out of a complex twisted roof form to the lidar scans needed to analyse the potential shading offered by shrubs, trees and obstacles in the wider site.

The materials for the project have been driven by a desire to understand the supply chains and impact of the construction. A precision cut timber frame by PH15 integrates low fi materials with advanced developments in timber fabrication to make a fully sealed structural envelope, with pumped insulation from recycled paper pulp. An outer layer of wood fibre insulation prevents any of the thermal bridging usually found in timber framed buildings. A lime render externally allows the building to breathe - and an overhanging copper roof is made from 100% recycled metal, both protecting the vulnerable render below the eaves and providing shading from the late afternoon sun to the upper level windows.

The project is due for completion in spring 2023.

Credits:

• Construction System - PhHomes
• Structural engineering - Foster Structures
• Film - Ryan Powell