1 Campden Hill, London - IKO Permaphalt mastic asphalt waterproofing system
Project Overview
IKO, in partnership with Fraden Contracts Ltd, delivered a comprehensive heritage roof refurbishment for 1 Campden Hill, a Grade II listed building of architectural and historical significance in London’s prestigious W8 postcode.
Originally designed in 1915 by renowned architect Edward Prioleau Warren, this iconic property sits at the heart of Holland Park and previously sold for £43,000,000 in 2020, establishing it as one of the most valuable homes in the neighbourhood – and indeed the country. The restoration project involved refurbishing the 200m² flat roof of this Edwardian structure, which had reached the end of its serviceable life.
With its heritage status protected under English Heritage, the renovation demanded a delicate balance between preserving the building’s original character and bringing it in line with today’s stringent fire safety and thermal performance regulations. This iconic redevelopment required materials that would complement these objectives while ensuring long-term durability.
Challenges
Restoring the roof of a Grade II listed building presented significant challenges. The primary challenge was the need to harmonise strict heritage preservation requirements with modern performance standards for fire safety and thermal efficiency.
This required extensive collaboration between roofing specialists, conservation bodies and the principal contractor to develop a strategy that would honour the building’s original character while delivering a futureproof solution.
Access was another significant hurdle. The building’s multi-level roof and confined spaces demanded careful planning and precise movement of operatives and materials. Located in a densely populated residential area, logistics had to be tightly controlled to ensure minimal disruption to neighbours.
Technical challenges were exposed around the numerous roof penetrations. Features such as roof lanterns, domelights, a chimney stack and parapet outlets required custom detailing to ensure waterproof integrity without altering the historic appearance of the structure.
Solution
IKO Permaphalt was selected as the waterproofing system of choice for its proven performance in heritage settings. As a polymer-modified mastic asphalt, it offered a seamless, robust solution that could be expertly applied to complex details without compromising the appearance or historical value of the structure.
Its long service life, BBA certification and 20-year guarantee made it particularly well-suited to this sensitive project. In addition, its environmental credentials, locally sourced raw materials and UK-based manufacturing supported broader sustainability goals.
The works began with the installation of an IKO self-adhesive vapour control layer, followed by thermal insulation compliant with modern building standards. A black sheathing felt was applied as a base for two coats of roofing-grade IKO Permaphalt, installed to a total thickness of 20mm across the roof’s existing falls and cross falls.
Upstands and parapets received a three-coat application of asphalt on expanded metal lathing and black sheathing felt. Additional scope included intricate weathering and flashings around roof penetrations, as well as the installation of a man-safe system with nine anchor posts to support future maintenance.
Results
Throughout the process, the team maintained close coordination with English Heritage and principal contractor Size Group London. Every decision from material sequencing to detailing was made with both heritage preservation and performance longevity in mind.
Quality control was meticulously managed through phase-by-phase inspections from Fraden Contracts management and IKO engineers, as well as regular photographic documentation, resulting in a flawless execution that met the expectations of all stakeholders.
The result is more than a renovation, it’s a perfect balance of heritage conservation and modern performance. Through close collaboration between Fraden Contracts Ltd and IKO, the historic character of 1 Campden Hill has been preserved while providing a roofing system that protects, respects and will endure for years to come.
Project name and location:
1 Campden Hill, London
Main IKO system:
Project sector:
Residential
Contractors: