The superior airtightness performance qualities of the Wraptite® air barrier system
from the A. Proctor Group will enhance a new state-of-the-art development at St
Dunstan’s College - a co-educational independent school in Catford, London.
Contractor Willmott Dixon will deliver the new Junior School, STEM building and Sixth Form Hub at St Dunstan’s.
Designed by Bond Bryan Architects, the new development will be sited adjacent to the existing historic Headmaster’s House and connected by a glass atrium. Phase one includes a new junior school with specialist facilities for art, music and performance, and phase two includes the construction of the STEM Centre and Sixth Form Hub.
A vital element of the design and construction is to maximise the energy efficiency of the new buildings: Wraptite airtightness membrane, the only self-adhering vapour permeable air barrier certified by the BBA, will form a crucial part of the solution.
The inclusion of Wraptite within the facade will ensure “as-designed” performance, narrowing the gap between as-designed and actual energy performance and reducing the likelihood of potential failures to meet required airtightness levels.
Wraptite is a self-adhesive breather membrane applied externally, quickly and efficiently as part of the rainscreen system. The self-adhesive Wraptite membrane fully bonds directly to the substrate, requiring no mechanical attachment and little seals or tapes to suppress air leakage around junctions or penetrations.
Wraptite combines the critical properties of vapour permeability and airtightness in one self-adhering membrane, providing high levels of protection to the building fabric beneath the cladding. As a result, the Wraptite system allows the substrate beneath to dry quickly and moisture vapour to escape and reduces the likelihood of mould, mildew, condensation, timber distortion and metal corrosion.
Wraptite is compliant with Part B regulation changes and also has BBA approval for unrestricted use in buildings over 18m in England and 11m in Scotland.
|Roll Size||1.5 x 50 m|
|Thickness||Calibrated Deadweight Micrometer||0.65 mm|
|Weight||Electronic Weigh Scale||292 g/m2|
|Application Temperature - Air & Surface Minimum||-10 C|
|Service Temperature||-40 to 80 C|
|Water Penetration - Before Ageing||EN 1928:2000 Method A||W1 Class|
|Water Penetration - After Ageing||EN 1928:2000 Method A||W1 Class|
|Air Permeance||EN 12114||0.01 m3/m2/hr @50Pa|
|Water Vapour Resistance Sd||EN ISO 12572(C)||0.039 m|
|Water Vapour Transmission||BS 3177:1959||893 g/m2/24hr|
|Peel Adhesion||EN 1939||5.01 N/10mm|
|Tensile Strength - MD||EN 12311-1||417 N|
|Tensile Strength - XD||EN 12311-1||252 N|
|Tear Resistance - MD||EN 12310-1||412 N|
|Tear Resistance - XD||EN 12310-1||286 N|
|Dimensional Stability - MD||EN 1107-2||0.3 %|
|Dimensional Stability - XD||EN 1107-2||+0.1 %|
|Reaction to Fire||EN 13501 - 1||B Class|
|Flexibility at Low Temperature||EN 1109||No cracks at -40C|
|Wraptite - BIM Object - Steel Frame||RVT IFC|
|Wraptite and Facadeshield UV - BIM Object - Steel Frame||RVT IFC|
|Wraptite - BIM Object - Steel Frame With Reflectite Tape Over Board Joints||RVT IFC|
|Wraptite - BIM Object - Steel Frame Wraptite Tape Over Board Joints||RVT IFC|
|Wraptite - BIM Object - Wraptite Tape Over Board Joints||RVT IFC|
|Wraptite - BIM Object - Ventilated Timber Frame With External Airtight Membrane Wraptite||RVT IFC|
|Wraptite - BIM Object - Ventilated Timber Frame With External Airtight Membrane And Wraptite Tape Over Board Joints||RVT IFC|
|Wraptite - BIM Object - Warm Roof Slate With Softwood Sarking||RVT IFC|
|Wraptite - BIM Object - Warm Roof Tile With Plywood Sarking||RVT IFC|
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.