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2016 ¥ 6 ∂
Roofs and Drainage
Putting the heat on
Restoration, but without the drama
Icopal’s Parabit Duo and Solo Hot Melt Membrane Systems are designed to provide optimum waterproofing, allowing large roof areas to be covered quickly. Duo flexible monolithic waterproofing membrane is a blend of bitumen synthetic rubbers, polymers and other additives, combined with a spun-bond polyester fabric and high-performance elastomeric membrane. The bitumen compound is heated to a liquid and applied directly to the structural deck, forming a full and continuous bond to the substrate.
Welsh Slate’s natural Cwt Y Bugail Countygrade roof slates feature in the refurbishment of a historic seaside villa in the conservation area of Lyme Regis in Dorset. Some 150 m2 of various-sized slates were used on the stables and Grade II* listed main house, now a Landmark Trust holiday let. The £1.8 million restoration of the 18th century property, above, complete with observation tower took two years, but the roof design was straightforward, with a parapet gutter to the front, valley gutter in the centre and drain to guttering at the rear. The slate was specified not least for its quality and longevity but also because it was the original material, so it needed to be in keeping with the building. The trust said it favours natural products which are in tune with historic buildings.
Solo is described as notably time-efficient, as the multiple waterproofing layers are installed in a single operation, and detailing such as upstands and plinths can be completed before main system application. The systems are said to be particularly compatible with four types of roof build-up: inverted roofs, plaza or podium decks, terraces and balconies and green roofs. Extensive or intensive green roof build-ups can be installed above the completed hot melt waterproofing layer, acting as a ballast and water-attenuation system. ¥ Icopal United Kingdom � +44 (0)161 865 4444 www.icopal.co.uk
An existing Welsh Slate roof has also been renewed on a Grade ll listed building at the heart of London’s King’s Cross regeneration project. More than 600 m2 of 500 ≈ 300 mm Penrhyn Heather Blue County-grade slates were used in the refurbishment of the 1860s German Gymnasium – the first purpose-built gym in England – in its new guise as a designer restaurant. Said Andrew Rixson of architects Allies and Morrison, “The design of the roof is complicated by the increased
depth of the new roof build-up in that the additional thickness of the roof sets the new slate tiles above the level of the brickwork details of the existing gable parapets. “To resolve this, our design approach separates the slates from the brickwork by introducing hidden gutters, valleys and leadwork detailing around the perimeters of the roof. These details are adapted into various different forms due to the variety of conditions found within the existing roof and the deformation of the timber roof structure over time but they reconcile the precisely constructed new roof elements with the unevenness of the Victorian brickwork.” Penrhyn Heather Blue slates were also used in the redevelopment of the northern end of York racecourse, as seen below, to complement the listed buildings – on the stables, which feature a 30� roof pitch, on the circular roof of the Winning Connections building and on the 40� pitched roof weigh-in building, which features mitred hips and valleys and concealed gutters. ¥ Welsh Slate United Kingdom � +44 (0)1248 600656 www.welshslate.com