Lynton House | EnerPHit in Conservation area

Arboreal Architecture delivered a highly specialised retrofit project, transforming a deteriorated building into one of only a handful of EnerPHit-certified homes in London - currently just nine (May 2026). This places the project within an exceptionally rare category of high-performance retrofits, demonstrating advanced technical capability in both conservation and low-energy design. The scheme not only meets the rigorous Passivhaus Trust EnerPHit standard, but also proves that such outcomes can be successfully replicated across similar historic housing stock.

The project carefully balances performance and heritage. The existing structure was upgraded to achieve a 90% reduction in space heating demand, while reinstating the building’s original architectural character. A holistic fabric-first approach ensured a “moisture robust” construction, critical in retrofitting traditional buildings. The removal of inappropriate modern alterations - such as gravel dash render and mismatched windows - allowed the façade to be restored using a mineral render and bespoke timber triple-glazed sliding sash windows. These were precisely detailed to match original proportions and align with neighbouring properties, ensuring compliance within the Kilburn Conservation Area.

Internally, the layout was reconfigured to better serve contemporary living, including the conversion of the loft into a high-quality usable space. The result is a seamless integration of historic sensitivity, spatial improvement, and cutting-edge environmental performance - positioning the practice at the forefront of EnerPHit delivery in London.

Location: Maida Vale, Kilburn, London

Property type: Victorian Terrace

Scope of work:
We led the full retrofit strategy, including conservation-led façade restoration, interior reconfiguration, loft conversion, and a comprehensive fabric upgrade to meet EnerPHit standards. The role encompassed design development, technical detailing, coordination of bespoke elements, and delivery of a high-performance, conservation-compliant retrofit.

Key Features:

• EnerPHit-certified retrofit meeting Passivhaus standards for existing buildings

• 90% reduction in space heating demand

• Fabric-first approach ensuring long-term energy efficiency and durability

• Moisture-robust construction tailored to traditional building fabric

• Bespoke timber triple-glazed sliding sash windows with heritage detailing

• Mineral render façade restoring original architectural character

• Conservation area-compliant design (Kilburn)

• Loft conversion and improved internal spatial configuration

Project Achievements:

• One of only 9 EnerPHit-certified homes in London

• Demonstrates replicable model for high-performance retrofit in historic contexts

• Successfully balances heritage preservation with advanced environmental performance

• Significant operational energy reduction without compromising architectural integrity

• Establishes Arboreal Architecture as a specialist in complex, low-energy retrofits

More information about EnerPHit at: UK Certified Passivhaus Projects.