2015 Murdoch Award Winner – Rygar House, London – Lead-Tech Roofing Ltd
Consistency of design and workmanship was the key to the aesthetics of this large project involving flat, pitched and vertical panels and again working in partnership with the architect enabled design changes to be made to improve the long term integrity of the roof.
Martin Walsh reports that this new development is set in the heart of Mayfair in central London. Lead-Tech were appointed through the Main Contractor 800 Group Ltd to install all the roof timbers and new code 6 lead sheet to the crown flat roof, as well as the 70º Mansard Roof and the vertical sections, which also included code 6 lead to dormers and associated flashings. The total project was some 20 tonnes of lead sheet, supplied by Associated Lead Mills.
A key factor in securing the project was that as an LCA member, Lead-Tech could offer the 25 year insurance backed guarantee.
Once again the contractor and architect worked in close partnership and during the process of building the roof Lead-Tech were able to identify potential technical issues which might arise with the planned detailing and more importantly how the new lead roof would be ventilated. In most cases the Architects Drawings had been well thought out but when approached by Lead-Tech about their concerns, the architects allowed details to be altered as required.
Once the main roof construction had been completed and Lead-Tech commenced installing the new code 6 lead, they decided to reduce the setting out of the wood rolls to 575mm centres, thus ensuring the lead was installed well within its design limits. The wood rolls were staggered and included a ventilation ridge detail which was achieved using the Nicholson Air Track Products.
On the Mansard 70º degree pitched roof slope, Code 6 sheet was again installed at 575mm centres and the length of the bays were also reduced to 2.00 lm overall. At the head 3 rows of staggered fixings were installed using 38mm copper ring shanks.
The sizing and fixing of the bays have therefore been set well within its design limits, thus eradicating any future problems and potential failure of fixings, which is particularly significant as access would be problematic and costly.
It is this attention to detail that was recognised by the Murdoch Award judges.