Heathrow terminal 3 with Sealoflex

How do you complete a refurbishment of a 6300m2 roof at one of the busiest airports in the world with no impact on travel?
Liquid waterproofing

The Project

When it came to refurbishing the roof at Heathrow Airport a lot of considerations had to be made in order to minimise disruption. As an international airport operating 24/7, it was required that all works were carried out without any impact to passengers.

This affected the choice of materials, organisation of personnel and the logistics of getting staff and materials on and off-site. The specified System was Firesmart Pyrobar Carrier Membrane and Sealoflex Solvent Free liquid applied waterproofing.

  • Project name: Heathrow Terminal Three

  • Contractor: Mace

  • Sub contractor: Itech Roofworks


“Heathrow Airport required that the new roof be installed without affecting its operations, which is no easy task whilst building on the busiest airport in the country”

Itech Roofworks (Contractor)


The Guarantee

“One of the world’s busiest airport terminals is covered by a BMI 20 year guarantee and will not need anything but routine maintenance for decades.”

Itech Roofworks (Contractor)


The Challenge

The Challenge

Itech Construction Director and BMI’s Technical Support team surveyed the roof and found that several sections showed signs of long-term water damage that required replacing. A working plan was devised that allowed the damaged sections of plywood to be replaced without interrupting the activities of the terminal.

The plant rooms proved the most complex part of this project as they provided limited access for the operatives. Working at night, around extensive pipework and ducting, operatives had to strip the existing single ply, replace plywood, build bunding and weather with the Sealoflex system all within the confined space. This required thorough planning, immense skill and attention to detail to install.


The Solution

The Solution

The scale of the project meant setting up five teams, a total of 50 operatives, on both day and night shifts. The 24-hour operation consisted of the night shift stripping out the existing mechanically fixed Single-ply and installing Firesmart Pyrobar Carrier Membrane to the plywood substrate to create a weatherproof roof. The day shift then applied BMI Sealoflex Solvent Free Waterproofing Membrane if weather permitted or prefabricated the replacement sections.


The Impact

The Impact

The refurbishment was completed with little to no disruption to travellers, and the airport operated normally throughout the project. Now one of the world’s busiest airport terminals is covered by a BMI 20 year guarantee, and will not need anything but routine maintenance for decades.

Both the main and the sub-contractors managed the health and safety risk by following the Four steps to safety guide, these are to observe, engage, improve and don’t walk by – empowering all site members to recognise and challenge the actions of others. Itech also installed and managed extraction ventilation, required to ensure dust particles and bituminous odours did not enter the airport ventilation systems during installation. Any breach could have set off the fire alarms, causing chaos to the airport.


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