Maidenhill Primary School is a brand new, one of a kind establishment located in Newton Mearns, Glasgow, where a total of five Bauder systems were installed including a lightweight green roof and our innovative, penetration free photovoltaic solution. The client had worked with Bauder previously on the prestigious St James Shopping Centre in Edinburgh, and were familiar with the waterproofing systems, service and the product and workmanship guarantee. Our flexibility meant that various Bauder systems could be used across the five different roof areas.

The 2,385m² roof required a range of highly skilled contractors to create a seamless, high quality variety of roofing areas. The finished project has created an incredibly environmentally friendly setting for its students and teachers.

The specification

The client was looking for high quality, long lasting roofing systems. Sustainability and acoustic performance were identified as key factors in the design of the roof, and the client also required a single source supplier that could provide a guarantee for both products and workmanship. The client wanted to ensure a consistent level of quality with design and performance in mind, was kept across the number of roof areas. Bauder’s wide variety of systems and products meant we could meet all the sustainability objectives, and with our network of approved contractors carrying out the installation, we could offer a comprehensive guarantee.

1800 m² of Bauder Thermofol PVC single ply waterproofing system with BauderSOLAR F was specified for the lower roof of the project. Thermofol is a lightweight, fast track and cost-effective waterproofing solution that is resilient to the natural elements. It is flexible with a high tensile strength that is easy to install and weld and was also a perfect base for the photovoltaic solution installed above it.

BauderSOLAR F was specified to deliver an efficient energy generation solution. The mounting units were secured to the roof using a membrane-to-membrane welding technique at a 12° angle for maximum energy generation on the Single Ply Thermofol PVC System. This installation method means that the roof was not compromised by penetrations for fixings nor is it ballasted, which would add significant weight loading to the roof.

To meet the client’s requirements for a high-quality, long lasting waterproofing system, our first-class bitumen waterproofing, Bauder Total Roof System (BTRS), was installed to the plant decks and art terrace roofs. This heavy duty and robust system has a service life in excess of 35 years. 400 m² of Bauder Total Green Roof System (BTGRS) was also fitted to the lantern roof which incorporates our Plant-E cap sheet that has been tested by the FLL to ensure long-term root resistance, which is suitable for all Bauder green roof applications including the SB Sedum Blanket installed on this project.

Lastly, Bauder’s lightweight SB Sedum Blanket with Extensive Substrate was fitted on top of the BTGRS system. The sedum species in the blanket are selected specially to thrive in the demanding environment of green roofs. The mix gives a range of both sun loving and shade tolerant species so that the species best suited to the location of Maidenhill Primary School and its roof orientation will become prominent and surpass those that find the conditions less favourable. Typically, this mix includes 10-14 sedum species with some Saxifraga for early spring flowering to support pollinators. The SB Sedum Blanket is drought and wind hardy, perfect for the blusterous weather conditions of Glasgow, is low maintenance, and is a great way to give back to the environment and reduce the buildings carbon footprint.

Project challenges

The roofing works began during the winter of 2018, and so the membranes used were those that could be installed successfully in cold weather. Located high upon the edge of Glasgow, the site was incredibly prone to wind, and so wind calculations were extremely important on this project to ensure materials could be lifted onto the roof and, most importantly, that operatives could work safely each day. Bauder had to work closely with the roofing contractor and amend deliveries and plans at short notice.  The wind was monitored daily by BAM Construction and Procladd to ensure safe working and was a particular challenge for the operatives, having to work in such harsh conditions whilst remaining focused to guarantee the installation was of a high standard throughout. The potential impact of wind also dictated the specification of the green roof with Bauder recommending a heavier substrate sedum blanket system over a 40 mm drainage boards and 80 mm of Bauder supplied substrate. We also recommended larger rolls of sedum blanket to make to make the vegetation as heavy as possible.

There were some awkward details to complete where the single ply Thermofol membrane joined the BTRS roof areas which were planned in advance between the design team at BDP Architects, Procladd and Bauder to ensure a separation of the two non-compatible membranes.  Demanding door and window threshold details also had to be overcome which required regular meetings and discussions with Procladd site management and Bauder site technician, Francis Murray.

The result

Maidenhill Primary School is one of the largest photovoltaic projects Bauder has produced in Scotland, with 360 m² of BauderSOLAR F PV solution having been installed on top of our Single Ply Thermofol PVC waterproofing system. This project was unique due to the wide range of materials used over a variety of roofing areas, each with different requirements.

The acoustic needs for the roof was an important factor for the client, and so Bauder created a unique combination of our acoustic insulation, BauderROCK, along with our BauderPIR FA insulation to achieve the required thermal performance and U-value of 0.15 W/m²K, falls in the roof, and to meet the auditory requirements on the lower roof area.

The roof was given a full comprehensive guarantee in August 2019, and its doors opened to new students shortly afterwards.

Different systems were installed on different roof areas:

• Bauder Thermofol PVC
• Bauder Total Roof System (BTRS)
• Bauder Total Green Roof System (BTGRS)
• BauderGREEN SB with Extensive Substrate

BauderSOLAR F

The zero penetration installation of the PV components, modules and installation ensures the integrity of the waterproofing is upheld throughout. A high energy generation with a minimum of 16.82% panel efficiency.