The original waterproofing on the Maternity Hospital roof had exceeded its serviceable life and begun experiencing water ingress, requiring urgent remedial work. Bristol City Council wanted to optimise the roof area by installing a high quality, long lasting PV array that would contribute to its Solar City scheme that aims to provide one gigawatt of solar power to Bristol by 2020. The installation needed to cause minimal disruption to ongoing work at the hospital and insulation upgrades were necessary to ensure the roof achieved the required 0.25 U-Value.


Bauder’s premium bituminous system, BTRS, was specified because it is durable, robust and can withstand permanently sited loads of up to 2000Kg/m². The system build-up included Bauder’s 100mm PIR FA-TE insulation to satisfy building regulations, and its state-of-the-art PV modules were installed at a 10⁰ angle for optimum energy generation. The solar array consisted of 166 PV modules in total, enabling the hospital to generate at least 41.98 Megawatt Hours of solar power each year. The remarkable simplicity of the installation method also meant that the entire array could be fitted in just three days.

Bauder Building Board

Project: St. Michael’s Maternity Hospita
Location: Bristol
Roof Area: 1,170m²
PV Roof Area: 500m²
Specifier: Bristol City Council
Approved Contractor: Span Roofing

Applied Products

  • K5K is a bituminous capping sheet with a life expectancy in excess of 40 years.
  • PIR insulation has the best insulation rating of all widely-used flat roof thermal insulation materials.
  • The BauderSOLAR SOLfixx system was installed with 166 PV modules being fitted achieving 50kWp.

Bauder Total Roof System


Learn more about BauderSOLAR PV >>


Project specifier, Richard Lowe of Bristol City Council: “Bauder offered the highest degree of service and support throughout the project. We were delighted to find a single source solution of roof renewal with PV supply and fit, and with the complete roof finish covered by the Bauder guarantee we have total peace of mind over its future performance.” 

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