Students at George Hastwell School, an academy in Barrow-in-Furness for children with severe or profound learning difficulties, are now sheltered by a robust roof built to a specification from BMI UK & Ireland – a large manufacturer and distributor of flat and pitched roofing and waterproofing solutions – that is guaranteed to withstand the harsh coastal climate for 20 years.
The existing roof, which was built in the 1960s, was in a very poor state and there were concerns it could fail and injure the pupils, who range from two to 19-year-olds.
The school became an academy in 2015, which qualified it to apply for aid from the Schools Funding Agency. It then commissioned Liverpool-based surveyors Cunliffes, working with BMI, to draw up the school’s Capital Funding Application to the Agency to replace the original roofs.
Cunliffes determined that the roof should be stripped according to the BMI specification and that none of the existing system was to be left in situ, even though this process was both difficult and time consuming. This was done to eliminate any risk of the existing system deteriorating beneath the new waterproofing, causing it to fail and potentially parts of the roof falling into the building below.
The school is sited on Walney Island, right on the edge of Cumbria, and faces the gales and storms from the Irish Sea, so wind uplift calculations were required to find the best application method. The roof details were sent to the BMI specification team to complete the calculations and determine the correct fixing for the location.
The calculations showed that both the membrane and the insulation beneath would be subject to windloads of up to 2.79 kN/m2 (kilonewtons per square metre) at the corners. This meant that the insulation had to be bonded separately using TPI insulation adhesive – a foaming, odourless, VOC-free two-part rapid curing polyurethane adhesive manufactured from bio-renewable materials.
The 1,050m2 project, installed by BMI’s IMA- approved contractor Pendlebury & Sons, consisted of a number of roofs with either concrete or plywood decks. For the non-flammable concrete substrates, BMI Icopal Tecnatorch Sand and Siplast Primer were applied as the vapour control layer. For the plywood decks, the vapour control layer comprised BMI Icopal TorchSafe TA VCL Sanded and SA Primer.
Thermazone Torch On Insulation was then bonded to both vapour control layers with TPI Insulation Adhesive. Total Torch Vapour Dispersion Layer was installed as underlay, followed by Firesmart Thermaweld Capsheet in Charcoal to complete the waterproofing system.
Pendlebury & Sons is very experienced in working with BMI systems, and Contracts Manager Paul Worthington says the support offered by BMI is valuable.
“The technical assistance and site inspections are very helpful,” he says. “We get any help we might need with details, and the reports and photos provided to the clients after site visits gives them the confidence that everything is being done right and that we’re making progress as scheduled.”
Scheduling the works and co-ordinating with the school was particularly important, says Worthington, because the pupils needs meant that noise and disruption had to be kept to a minimum. Works on replacing the roofs began in late May 2018 while the school was still in term, with the noisiest work, such as stripping out the existing roofs, being done before or after school. The project was successfully completed in the first week of July 2018.
The George Hastwell School in Barrow-in-Furness now has a roof covered by a 20-year BMI guarantee – ensuring it will perform in extreme coastal conditions for decades, keeping its pupils safe, warm and dry.