The flexibility of the Sika Sarnafil single ply system and the expertise of roofing contractor Midland Single Ply (MSP) have lent themselves to a bespoke and intricate roof crowning the home of West Berkshire Council in Newbury.


A key part of the West Street House’s design is the mansard roof, which houses the top office floor and 25 dormer windows. Tasked with installing 800sq m of membrane to the flat roof and sloped edges, MSP’s experience as a Sika Sarnafil registered contractor enabled them to successfully overcome a number of technical challenges.


Visible from ground level, the overall aesthetic finish of the roof was a vital consideration in the specification of the single ply system. Changing from the originally specified membrane attached with adhesive, MSP opted for a mechanically fastened Sika Sarnafil S327-15EL single ply membrane, chosen for its flexibility and suitability to complex detailing.


MSP were required to work in close partnership with the project’s building contractor, Francis Construction, who were replacing each individual dormer window during the single ply installation. For each refit, MSP were responsible for the precise window detailing, securing the membrane in place with a Sarnametal window reveal.


Faced with the difficult shape and almost vertical pitch of the mansard roof, each window reveal was unique in size and required precise measurement and bending to fit. As well as this, throughout building works, the council office remained fully operational and MSP and Francis Construction had to manage each installation to make sure the top floor offices would be missing the minimum number of windows at any one time.


As one of the few roofing contractors with the machinery to cut and bend metal, MSP were ideally suited to the project’s demands. With this facility, they were able to measure and create each individual reveal overnight, enabling it to be refitted the next day and ensuring the window spaces would be empty for the shortest time possible.


Dave Burgess from MSP explains the outcome: “This project required an extremely intricate installation, and our metal bending facility meant we were able to cut and bend each Sarnametal reveal on demand. With this, we were able to work successfully with Francis Construction and ensure the building could remain fully operational throughout building works.”


He adds: “We had never had the requirement for metal to be measured on site one day, cut and bent overnight and then fitted on site the next day in a job before, or had such tight critical path installation deadlines, but we are very pleased with the outcome. It was critical that the Sika Sarnafil membrane was fitted to be aesthetically pleasing as well as being accurately measured and fitted, and we’re confident in the project’s success.”