Articles | Exterior Systems
GIB Weatherline® Tapes
Tuesday, 15 October 2019
By Hamish Ewan
GIB Weatherline® Tapes have been developed and tested for use in GIB Weatherline® Rigid Air Barrier Systems. But why are they necessary and what do they do?
Why are GIB Weatherline® tapes necessary?
GIB Weatherline® Tapes have been specifically developed and thoroughly tested for use in GIB Weatherline® systems. They perform a critical function in creating a permanent and continuous seal at sheet joints and around sheet penetrations. When used in conjunction with GIB Weatherline® sheets they help manage the air pressure that can act on the exterior of a building which has the potential to drive rain water through the exterior cladding.
Types of GIB Weatherline® tapes
Most sheet joints and penetrations are sealed using GIB Weatherline® Flashing Tape. This product comes in a variety of widths to help minimise tape wastage. GIB Weatherline® Sill Tape is made of self-adhering, stretchable butyl rubber and are used to seal the base of the window sill opening prior to window installation.
A range of Pro clima Kaflex KAFLEX or ROFLEX penetration sealing grommets are also available to seal a variety of building service penetration sizes.
How do GIB Weatherline® tapes bond?
GIB Weatherline® sheets may appear smooth at first glance, but under close examination the surface will comprise of hills and valleys. The adhesive on the tape flows into these areas and keys into the sheet surface.
If the adhesive is in direct contact with the sheet surface, attractive forces (also called Van der Waals forces) will result at a molecular level. The closer the adhesive comes to the sheet surface, the more these forces come into play and the greater adhesion strength between the sheet and the tape.
This is why it is recommended to use a GIB Weatherline® paddle or similar paddle to help create strong and consistent surface pressure on the tape when applying it to the sheet surface. The strength of the adhesive bond between the tape and sheet surface builds up over a period of hours.
Durability and NZBC Compliance
As part of the wider GIB Weatherline® testing programme, GIB Weatherline® tapes have undergone rigorous testing to ensure they are fit for use in NZ conditions. This includes BRANZ accelerated aged weather testing to simulate long term exterior exposure, GIB® Bracing and Fire system testing, and MBIE Guidance (Feb 2019) for External Wall Cladding System Vertical Fire Spread testing.
GIB Weatherline® systems are compliant with the relevant NZ Building Code requirements for rigid air barriers, are BRANZ Appraised 1048 (2019) for buildings within the scope of NZS 3604 and have Specific Engineering Design information available for buildings outside of NZS 3604