The first external fully adhered vapour permeable air barrier with full BBA certification been installed as a solution for airtightness, weather protection and breathability at the new administrative headquarters of the Royal College of Pathologists in London.
The Wraptite air barrier system from the A. Proctor Group is the only selfadhering vapour permeable air barrier certified by the BBA and combines the important properties of vapour permeability and airtightness in one self-adhering membrane. This approach saves on both the labour and material costs associated with achieving the demands of energy efficiency in buildings.
Designed by architects Bennetts Associates the new £15 million eight-storey building on Alie Street in Whitechapel will become the new home for the college and features a double-height reception area, flexible office space, a library, meeting and conference rooms and a 200-seat auditorium. Gilbert-Ash has been chosen to build and manage the project which aims to reach BREEAM Excellent assessment.
Cladding contractor Windell installed the Wraptite System as an external air barrier and alternative to a traditional standard breather membrane. The use of a standard membrane would have required mechanical fixing and provided some challenges given the concrete structure of the building. As an alternative, the Wraptite self-adhesive membrane was applied externally, quickly and easily to the external envelope in continuous pieces.
George Marcantonio, the Site Manager of Windell, commented: “The application of the self-adhesive Wraptite System has proven really easy to use, and quick to apply, with no requirement to return for additional fixing or accessories. We will certainly be using the system for future projects and recommend it without hesitation.” Unlike internal air barriers, which can be complex and costly to install due to the need to accommodate building services such as electrical, lighting, heating and drainage systems, positioning an air barrier on the outside of the structural frame simplifies the process of maintaining the envelope’s integrity, as there are less building services and structural penetrations to be sealed.
By reducing the likelihood of potential failures to meet designed airtightness levels, the Wraptite System helps ensure “as-designed” performance, narrowing the performance gap between as-designed and actual energy performance.
For any building to have an energy efficient, healthy, moisture free building envelope there is a clear need to manage the balance of Heat, Air and Moisture movement (HAMM) throughout the building’s life cycle from design, construction, completion and use.