Kemper System’s Kemperol 2K-PUR waterproofing system has been used on a further phase refurbishment of London’s historic Guildhall, this time to provide a new roof surface for the Guildhall Business Library.
The scheme follows the recent roof refurbishment of the Guildhall’s West Wing by main contractor Linbrook Services Ltd and involves overlay of a 300m2 asphalt roof featuring 56 pyramid rooflights. The brief to roofing contractor, A&L Roofing Services, was to complete the project within a six week programme, during which the library had to remain fully operational.
Guildhall selected Kemper System’s Kemperol 2K-PUR system for both projects as its solvent-free formulation enables an odour-free installation, preventing any nuisance odours affecting staff or visitors to the building. The cold liquid-applied system also made it possible to apply the waterproofing membrane precisely to the upstands and drainage channels of the 56 pyramid rooflights, which are located extremely close together in the central area of the roof, whilst seamlessly incorporating the entire roof.
The installation team began by cleaning and preparing the asphalt surface which had begun to blister and split. Kemper System’s Kempertec primer was then applied to stabilise the substrate and provide a chemical key for the waterproofing resin. Once this had cured, the waterproofing membrane Kemperol 2K-PUR was installed onto the roof. Applied in a single process, the Kemperol resin saturates a non-woven reinforcement fleece and cures to form a monolithic membrane that is UV stable, extremely tough, flexible and tear resistant, that bonds directly to the substrate.
Kemper System’s non-woven reinforcement fleece was cut to size and shape on site to enable the meticulous detailing and protection of the most vulnerable parts of the roof around the rooflights, outlets and upstands as well as the flat roof areas of the roof.
Lee Lane from A&L Roofing Services comments: “Keeping the library open during the six week programme meant that the old rooflights had to remain in place while the job was done before being replaced with new pyramid rooflights at the end. This made for a very challenging project which could really only be delivered by a cold-liquid applied system that can be applied accurately to the multiple facets and contours of the complex detailing. The fact that the Kemperol 2K-PUR system is eco-friendly as well as odour-free was an added bonus for Guildhall, and kept the refurbishment in line with The City of London’s sustainability aims.”