Due to the varying conditions of the roof construction(s)/substrates the preparation had to be thought through thoroughly. Certain roof areas needed to be scarified which would have caused reverberations through the roof/concrete deck. This would have possibly created contaminants by spooling of concrete/debris/dust to within the MF Compound Water Lanes/Tanks. After various meetings, additional protection was utilised and installed within the buildings above the Water Lanes/Tanks to ensure that any spooling of concrete/particles did not enter into the ‘Clean Water’ process as this could potentially have blocked the screens (filters). If the Water Lanes/Tanks had become contaminated during our works, the whole ’Clean Water’ process/system, may have had to be temporarily shut down.

Moisture was discovered beneath an identified area of one of the roof areas and the specification on this particular roof was changed with the client’s agreement. To aid in the dissipation of the moisture ’Mushroom’ vents were installed. This again was of huge benefit to the client because if the roof had been required to be completely stripped, the Water Process would have had to be temporarily suspended so this saved a huge amount of disruption to the ‘Clean Water’ process and the Client.

The River Intake Building was constructed of a ’Barrel Vault’ type construction which had a concrete rooflight detail with glazing blocks. Again the client wanted to keep the ‘Lux’ levels in the building but needed the roof to be watertight and guaranteed.

In order to provide a solution for this difficult challenge, the Polyroof Transglaze PU liquid was specified in conjunction with the Protec system. Transglaze is a translucent waterproofing system that permits the passage of light through the membrane into the interior of the building, minimising any reduction in light into the interior of the building. This system was carefully applied to the glazed blocks before the Protec system was laid over the concrete sections to complete the seamless waterproofing on these details.

Another complex detail to be overcome was the many internal parapet walls that divided the roof areas above one of the buildings. To ensure that water could drain from the roof, there were numerous through-wall outlets positioned at the bottom of these parapet walls, each one needing to be made completely watertight. This was one of the many reasons why a liquid system was preferable; by using appropriate small roller application tools, Williams Roofing Contractors Ltd were able to fully seal inside each on of these outlets.

With respect to the parapet walls themselves, the multi-surface ability of Protec meant that the system could be applied directly to the brickwork, saving the client further costs through eliminating the need to over-board. A key advantage of Protec is its high thixotropy, meaning it can easily coat vertical surfaces without the need for any additional thixo additives.

As you can see within the photographs some of the detailing within the various roof areas was very intrinsic, especially the MF Compound Building which had two number banks of ‘Sump’ type details present. A liquid applied membrane was the preferred product by the nature of the detail and undulations within roof construction, the client required a guarantee that would include difficult details.

The works were completed to an extremely high standard. The result was the full encapsulation of the roof areas, without a single detail left exposed to the elements. Following a final inspection by Polyroof, the roof was signed off for guarantee and the client was extremely pleased with the service and product they received.