Couzens House, 1 Weatherley Close, London

Project Overview

Couzens House is an apartment building in East London, where a 134m² balcony walkway deck over residential dwellings required refurbishment. The project involved stripping back the existing Spartan tiles and asphalt to the concrete deck before rebuilding the walkway with new falls, insulation, waterproofing and a renewed surface finish.

In a live residential setting like this, the works needed to improve the long-term performance of the deck while protecting resident access and keeping the homes below secure and watertight throughout the programme.

James Roofing installing IKO Permascreed LI and insulation on residential balcony walkway refurbishment project
Balcony deck waterproofing project at Couzens House featuring IKO Permaphalt and checker plate tile finish

Challenges

The main challenge was carrying out the works over occupied homes while maintaining safe day-to-day access for residents. Because no temporary roof was in place, the properties below had to remain watertight while the existing deck was stripped and rebuilt.

Introducing thermal insulation added a further constraint, as threshold heights had to be carefully controlled at the door openings. At the same time, new falls needed to be formed accurately across the deck so the rebuilt walkway could drain correctly and provide a reliable base for the new waterproofing system.

Solutions

IKO Permascreed LI was used to form new falls and provide a stable base for the waterproofing system. Its zero-water formulation and ability to be walked on and waterproofed once cooled helped maintain progress through the winter programme without the delays associated with wet or cement-based screeds.

It also contributed to reducing the carbon within the project, offering up to 38% lower embodied carbon than the original IKO Permascreed, a reduction in Global Warming Potential of up to 73.44kg per tonne, and third-party verified EPD documentation.

IKO enertherm MG insulation board was introduced within the rebuilt deck construction to meet thermal requirements, while careful sequencing helped protect threshold heights, maintain resident access and keep the homes below watertight throughout the works.

The finished build-up of IKO Permascreed LI, IKO enertherm MG insulation board, IKO Permaphalt mastic asphalt waterproofing system and checker plate tiles delivered a renewed balcony walkway deck designed for long-term serviceability over occupied homes.

Balcony deck edge detail showing completed waterproofing system at Couzens House, London

Project name and location:

Couzens House, 1 Weatherley Close, London

Main IKO system:

IKO Permaphalt mastic asphalt waterproofing system

Roof area:

134m2

Project sector:

Residential