Britannia Wharf overlooks the remarkable wildlife corridor of the reclaimed historic Basingstoke Canal, which offers local and long-distance walking and cycling routes through open countryside. Butler Brothers were engaged to complete the full roofing works, including the flat and pitched roof sections. The areas requiring a liquid system consisted of flat roofs, dormers and balconies. Insulation was required the main flat roof area to incorporate roof falls whilst achieving the required U-Value and PV panels were designed in to provide clean energy for the residents
The main challenges presented by this project was its complexity. The main flat roof areas were situated over multiple levels and plains. The perimeter of the roof was a combination of parapet walls and mansard edge details. The parapet walls adjoined pitched dormer roofs, and this interface was able to be made fully waterproof thanks to the use of Polyroof Protec System.
The PV cells were designed to be a loose-laid system and were fitted in strategic areas to make the most of the sunlight and provide the residents with clean, renewable energy. Another environmental consideration was the formation of a roof garden – creating an attractive recreational area that was also home to insects and other wildlife. These PV cells, along with the various other details, would require regular maintenance. Butler Brothers carefully formed a series of hardwearing anti-slip walkways to enable the plant to be accessed safely. These were formed through the embedding of an anti-slip grit into an extra layer of the Protec system, and sealed with PolyFinish resin to give an extra tough and durable finish.
This same system was utilised in the terraced areas. The hardwearing nature of flexible polyester technology meant the same liquid could be used for the flat roofs, terraces and balconies – a huge benefit for the installing contractor. The balcony warm roof system was waterproofed with Protec, and then a third coat to accommodate the anti-slip finish was incorporated.
There were numerous interfaces between pitched roof sections and the liquid roofing system. Each one was methodically completed to ensure the areas were left in a fully weatherproof condition.
A number of pipes and vents protruded through the roof, giving the opportunity for the liquid system to shine. Each detail was seamlessly and thoroughly made waterproof, without any of the weak points that may be associated with the welding / joining of rolled materials. All these details and challenges had to be considered within a tapered insulation scheme designed by Polyroof based on the architect’s details drawings. This required a high level of detailed planning and on-site implementation by the experienced roofing team. To help create a smooth, level finish a Polyroof SA Carrier Layer, a 2mm bituminous sand faced membrane, was laid over the insulation as a substrate for the Protec system. This also provided the additional benefit of rendering the installed insulation temporarily waterproof, meaning works could pause overnight without the risk of the installed insulation becoming wet.
The workmanship of the Butler Brothers team was second to none, and stringent QC and management processes were implemented to ensure standards throughout. A record of photographs and videos were taken every day to keep track of the installation process. The Contracts Manager for the project visited at the beginning of the installation process and at multiple times during the installation. Polyroof’s Technical Services regularly visited the site to carry out inspections, assisting where needed to ensure the project was meeting the necessary standards. The ongoing inspections were communicated with key project stakeholders, ensuring information was shared in a timely and effective manner
From a project management perspective, Butler Brothers assigned Foreman and a Contracts Manager to work closely with the operatives and the client.
Another key stakeholder was the HSE consultant who worked closely with the client to resolve sequential access issues including scaffold arrangements. The HSE consultant visited site before work started to generate RAMS to ensure the safety of the team. Due to the complexity of the build, there were many access issues that needed to be resolved. Additional hand rails were requested and installed on many areas of the roof to ensure a safe working environment.
The project was completed on time and to the client’s budget. The finished works highlight the benefits of liquid systems brilliantly – no other technology could make such a complex roof waterproof in such an effective way.