Cromwell Galleries- Proteus Waterproofing

Cromwell Galleries, South Kensington


Proteus Pro-System® Plus (Mid Grey)

Infallible Systems Ltd

Cromwell Galleries, located in the heart of South Kensington’s Museum district and housed within five Grade II listed buildings, stretching across 35,000sqft were designed in 1858 by Sir Charles James Freake. Through delicate restoration, the Georgian townhouses have been individually renovated to create permanent and shared offices, temporary exhibition space, viewing rooms, art storage, technician hire, working facilities and a Club Room where some of the most established collectors, dealers, curators, and arts professionals can collaborate and flourish. This wonderfully elaborate roof presented significant installation complexities. The unique trapezoid roof shape is made up of seven welded frames held together with over 1500 weather screen metal support brackets. A Proteus Pro-System® Plus Insulated Built Up Roof system was the perfect choice of waterproofing to ensure all complex detailing and shapes could be easily protected. Proteus Waterproofing worked closely with the roofing contractor, Infallible Systems Ltd, to assist the main contractor and architect with the design and installation of the waterproofing.

Prior to work commencement, Proteus conducted a roof survey, condition report and provided a bespoke specification giving the client a comprehensive understanding of the issues, and offering them the most practical, cost effective, and durable waterproofing solution. Design meetings were carried out with the Proteus Technical Department to ensure that all applications, thermal performance, and regulations were achieved, taking into consideration the insulation thickness to the limited heights of the weather screen bracket fixing holes. Detail drawings and work installation plans were put in place to run alongside the weather screen contractors to ensure a complete understanding from all trades working on these complex roofing works.

This project possessed many design and installation challenges. The Gallery’s trapezoid shaped main roof consisted of standing pitched roof lights and vertical walls, leading to ground level. The north light designed roofs were individually installed with Proteus Pro-System® Plus BUR waterproofing. The Pro-Vapour Control SA membrane was installed over the primed roof deck, and the AVCL was cut into individual pieces to allow installation around the fixing brackets and challenging detail areas. Thermal pads were primed before the metal fixing brackets were secured into position to hold the weathering screens. It was vital that all works were well organised and remained on schedule to allow the screens to be installed.

Proteus Pro-Therm PIR Insulation boards were measured and cut around the fixing brackets, then dry laid to ensure correct positioning. They were then adhered to the AVCL with Pro-Bond Foaming adhesive, resulting in no gaps or cold bridging risks. To prevent the insulation board bonding incorrectly to the AVCL, and the insulation build up from sliding down the roof, a stop end was fixed at the bottom of the pitched roof. Pro-Carrier Membrane SA was cut into individual sections to allow installation around the fixing brackets and window frame details. Once the built-up insulated installations were complete, the fully reinforced Proteus Pro-System® Plus waterproofing system could be installed.

Firstly, an embedment coat consisting of Proteus Pro-System Plus® and Pro-Force reinforcement were applied to the upstand underneath the window openings, terminating under the windowsill. This had to be applied around the window openings first to ensure that the EDPM window membrane could be adhered to achieve termination. Each individual roof section was embedded, followed by a final application of Proteus Pro-System® Plus Top Coat, leading into the central and perimeter box gutters.

High level link bridge roofs above living spaces were designed with a Cut to Fall Insulation Scheme to ensure sufficient rainwater drainage into central channels, incorporating the metal fixing brackets. These brackets were encapsulated with Pro-Vapour Control SA before the Proteus Pro-Therm Tapered Insulation PIR was installed in conjunction with detail/bracket heights. Each individual tapered insulation board was carefully measured and cut to accommodate the fixing brackets, while ensuring the fixings holes in the brackets were above the insulation/waterproofing surfaces. Tapered scheme finishes were overlaid with Pro-Carrier Membrane SA and adhered with Pro-Prime® SA, then fully encapsulated with Proteus Pro-System® Plus and Pro-Force embedment. All metal fixing brackets were coated with Pro-Epoxy Primer before dressing with the Proteus Pro-System® Plus waterproofing. Proteus Pro-System® Plus Top Coat was applied to all areas of the flat roofs and detail areas.

A concrete lift overrun roof located in the lower basement area was overlaid with Pro-Carrier Membrane SA and adhered with Pro-Prime® SA to provide a reinforced, waterproofing layer. Cold Melt® was applied to these tight accessible areas because of its cold applied, odourless properties, and ease of application. These areas are used for M&E and required a buried waterproofing system that can withstand the weight of concrete slabs on pads and machinery. A LowK Water Reducing Layer was installed under the slabs to protect the waterproofing. All waterproofing was leak tested to eliminate any damages and penetrations.

To ensure the project was completed to the highest standard, it was crucial that the main contractor, Infallible Systems Ltd, Proteus Waterproofing, and all design/installation teams maintained regular contact. Weekly site inspections were carried out by Proteus Waterproofing to inspect the progress and installation of the works, offering product and application advice where necessary. Photographs were taken throughout each stage to evidence the high-quality installation of the BUR/waterproofing layer.

On completion, all sections of the roof were leak tested to eliminate any breaches in the waterproofing. A sign off report was issued which included details and photographs of the finished works, enabling the contractor to apply for a guarantee on behalf of the completely satisfied client.

The Covid-19 outbreak brought unprecedented challenges to all construction sites. Unfortunately, the site had to close for 4 weeks, which could have caused huge delays in the progression of works. When site was able to reopen, Covid-19 restrictions and regulations were implemented alongside existing health and safety regulations. All roofing contractors and members of Proteus staff attending site were provided with the correct personal protective equipment including high visibility jackets, hard hats, and steel toe boots. The use of face coverings and hand sanitiser were also required. The site was well managed by Covid-19 marshals who were responsible for checking site attendee’s temperatures and issuing hand sanitiser prior to site access. As well as reducing staff members and splitting work shifts, all site operatives had to: maintain a two-meter distance between each other, where possible, work side-by-side or face away from each other to avoid face to face contact, follow one-way systems on walkways, and take staggered breaks in the safe outside areas provided. Sanitising stations were created throughout site to ensure good hand hygiene and prevent the spread of the virus.

Protecting staff from noise pollution is always crucial on busy sites. Designated noisy work times were implemented to reduce noise pollution and protect all site attendees. Avoiding the risk of fire was of utmost importance. As Proteus Pro-System® Plus is cold installed, it complies to the projects Health and Safety criteria, completely eliminating the risk of fire. It is also low odour which was beneficial as there was a permanent scaffold canopy and other trades working in the same areas. To ensure the works can be maintained safely and efficiently, man safe systems were installed to provide safe access for maintenance.