Refurbishing the roof of the UK headquarters of the official worldwide IT partners to the 2012 London Olympic Games was always going to be a tough call but IMA-approved contractor McCormick Flat Roofing completed the five-month project on time, on budget and with no defects, thanks to Icopal’s systems.

Main contractors ISG Interior Exterior PLC were so impressed they awarded McCormick an additional 4,000m² using Icopal’s Sureweld TPO system that was the mainstay of the original 3,300m² project. The project also won McCormick the runner’s-up award in the single-ply category at this year’s IMA Contractor of the Year Awards.

The work was carried out at Triton Square, London, home of the International Olympic Committee’s IT partners Atos Origin and of the data centre for northern Europe of JPMorgan Chase & Co, the leading global financial services firm and investment bank.

Although the 179,000ft² building, managed by Broadgate Estates, is vast the roof was a tight space to work on for McCormick’s due to a circular glazed atrium that took up most of the floor area and a large amount of plant and equipment sited around the perimeter. The 35-metre wide atrium was reported to be the largest atrium over a trading floor in Europe when the main tenant moved into the building.

Work involved the complete removal of the existing inverted roof, comprising pebble ballast, insulation and paving slabs, using skips craned to the roof.

“We co-ordinated all cranes and trucks for the removal of the existing roof coverings,” said McCormick’s managing director Stewart McCormick.

The existing asphalt substrate, which had severely ponded, was then cleaned off and concrete screeding carried out to the worse areas to eradicate all hollows. A vapour control layer was then applied prior to fully bonding SLM insulation boards using polyurethane adhesive.

SureWeld TPO fleeceback membrane was then fully bonded to the insulation boards using SureWeld fleeceback adhesive. Perimeter edges were treated with a powder coated trim in a matching RAL colour to the existing curtain walling and this was weathered using SureWeld TPO PS cover strip.

Work was carried out over the winter and more than 500 penetrations made to the existing roof deck, to allow concrete pads to be built to support the steelwork bearers for air handling units, each of which required detailed waterproofing using SureWeld flashing.

“But not one leak was experienced throughout the whole project,” said Stewart McCormick.

Sureweld TPO is a PVC-free membrane manufactured from advanced Thermoplastic Polyolefin. This provides the advantage of being able to demonstrate the UV and heat resistance of EPDM rubber but has the heat welding capability of PVC.

It is also inherently flexible and highly malleable, even at low temperatures, making it an ideal choice for complex roof designs. Durable and formulated for the long-term, its reinforcement provides high puncture and tear resistance, making it easy to maintain years after installation.

The completed Sure-Weld TPO system is covered by a 20-year insurance-backed guarantee, has BBA approval and FAA Fire Certification.

Email: tracy@tlcpr.co.uk