Full recovery of Lewisham Hospital roof with Kemperol

Kemper System’s Kemperol 2K-PUR solvent-free and odourless liquid waterproofing system has been used to refurbish the roof of Lewisham Hospital’s main entrance and outpatient department.

Ensuring the project avoided any disruption or nuisance to staff and patients in the unit or the surrounding wards, the cold-applied solution was installed on the 1,600sq.m roof area by contractors, Noble House Services (UK) Ltd.

The existing felt roof above the main building had failed and so Kemperol 2K-PUR system was selected to provide a durable and long-lasting waterproofing solution at the hospital.

Contractors first cleared the roof of all redundant services, removing as much as feasibly possible without causing disruption to the running of the hospital. The existing asphalt roof was then cleaned and the Kemper System Kemperol 2K-PUR was applied directly to the existing roof coverings in a single wet on wet process.

Reinforcement fleece was laid directly onto the first application of wet resin, immediately followed by more resin on top to ensure complete saturation of the reinforcement fleece. This provided visible assurance the correct amount of resin had been used throughout, and a consistent depth of coverage and membrane thickness is achieved. Once cured, the system forms a seamless, elastomeric waterproof membrane that cannot delaminate, is UV stable, and creates a strong bond directly to the substrate.

Contractors then installed a closed-cell, 160mm extruded polystyrene (XPS) insulation board before installation of concrete faced 50mm insulation board, followed by paving slabs to the perimeters to add additional ballast to the inverted roof build-up.


The roof area had a number of complexities with many ventilation outlets, up-and-over staircases and walkways, steel beams supporting the units on the roof, as well as upstands and roof hatches for access. Because Kemper’s waterproofing system is roller-applied, operatives could easily install the resin underneath the units and around the complex roof structure.

The solvent-free and odourless qualities of the Kemperol system also meant minimum disruption at the hospital throughout the application process. No hot works were required as part of the refurbishment, further reducing potential health and safety risk, and no wait time between applications of resin.

Matthew Bigley, Capital Projects & Estates Manager at Lewisham and Greenwich NHS Trust, said: “The roof area which needed attention was above the main entrance as well as Radiology, Cardiology and MRI departments - all very important sections of the hospital building. Refurbishment of the roof using Kemper System has provided higher thermal performance and energy saving benefits for the building. We are extremely pleased with the finished project which was completed on time and within budget.”

Contractors were able to install the Kemperol liquid waterproofing system quickly and safely despite the complexity of the roof area.

Gerry Ogborn from Noble House Services (UK) Ltd, added: “We didn’t experience any issues when installing Kemperol 2K-PUR. This project could have presented a number of problems and time delays if an alternative roofing material was specified, but it was not only easy to transport with minimal materials and apparatus to carry, but the liquid- applied resin meant we could get underneath and around the complex roof structure and detailing with ease.

TEL: 01925 445532 37


Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36  |  Page 37  |  Page 38  |  Page 39  |  Page 40  |  Page 41  |  Page 42  |  Page 43  |  Page 44  |  Page 45  |  Page 46  |  Page 47  |  Page 48  |  Page 49  |  Page 50  |  Page 51  |  Page 52  |  Page 53  |  Page 54  |  Page 55  |  Page 56