Kemper protects St John’s and St Elizabeth Hospital

Kemper System’s cold-applied liquid waterproofing solution has been specified for a multi-million-pound extension at St John’s and St Elizabeth (HJE) Hospital in the St John’s Wood area of London.

The £35m new build development has created six, hi-tech theatres and a day case suite which is one of the most modern in the UK. The extension also includes a new admissions lounge, imaging department, consultant rooms and an expanded Urgent Care Clinic.

A total of 9,060sqm of Kemper System’s Kemperol 2K-PUR solvent-free and odourless waterproofing membrane has been applied beneath the building’s green roof, onto a pedestrian trafficked walkway, the lower roof area and a plant roof area. The cold-applied solution was installed by London-based Ridgewell Flat Roofing Ltd.

Contractors had a strict timescale to adhere to, meaning a quick and easy application solution was required to complete the job.

Because of the location of the new build extension, adjacent to an occupied hospital building at HJE, the solvent-free and odourless qualities of the Kemperol system meant minimum disruption at the hospital throughout the application process. No hot works were required as part of the project, further reducing potential health and safety risks, and meaning no wait times were needed between applications of resin.

Once cured, the system forms a seamless, elastomeric waterproof membrane that cannot delaminate, is UV stable, and creates a sturdy bond directly to the substrate.

Additionally, the plant roof area had a number of complexities with many ventilation outlets and air conditioning units, and because Kemper’s waterproofing system is roller-applied, operatives could easily install the resin underneath the units and around the complex roof structure.

The new building, which is opening in planned stages throughout 2022, follows a recent £3.5 million ward refurbishment.