The Solution

Core samples established that there was a concrete deck, 30mm of asphalt, 30mm of PIR insulation and 30mm of asphalt, which was finished with a single layer of felt. This build-up was dry and in good condition.

The solution was to use the existing waterproofing as the vapour control layer and overcoat it with a new BUR solution, which would help to speed up the project and reduce costs.

After cleaning and priming the roof, the contractor Stephen Lawrence Ltd, laid the new warm roof system, which consisted of Centech PIR insulation, Centech SA Carrier/VCL and the Centaur Standard 20 BUR solution to provide long-term seamless waterproofing.

The new roofing solution increased the thermal performance of the roof to meet current regulations and achieve a U-value of 0.16 W/m²K.

There were a number of curved bay roofs on the front elevation of the building which had to be built up. A bespoke detail edge trim was constructed to match the contours of the roofs and the liquid waterproofing was then seamlessly applied.

There was a change in level on some zones of the roof and these areas were built up so that the Centaur Standard system could be applied before being fully encapsulated.

The Centaur solution is a liquid membrane, which utilises a GFM matting, so it was able to accommodate the detailing on the roof, which included plant and free-standing equipment, plinths and stanchions and cables and pipes.

Existing walkways were also treated with the Centaur system, which was then followed by Centaur Quartz Grit to provide a smart anti-skid finish.

All Centaur solutions are cold-applied, which eliminated the need for high-risk hot works on the roof. They are also safe and ultra-low odour in nature, which meant the residents were not put at risk by any strong odours or dangerous substances during installation.