40 Below™ Flashing Tape is a self adhesive flashing tape to seal around windows, doors, and other joinery openings as a secondary defense against water penetration.
Passes nail seal ability to ASTM 1970-01 per AAMA 711-07 and is suitable as a
single layer application over timber frame.
Not suitable where screw sealability is required
Has been CodeMark Certified by Certmark International
For a risk score between 0-20 in accordance with
NZBC Acceptable Solution E2/AS1
Passed NZS3604 Building Wind Zones up to and including ‘Extra High’
40 Below™ Flashing Tape- Advantages
Compatible with all building wraps
Incredible adhesion in all conditions
Simple 4 step installation, save time reducing costs
Extremely thin only 0.2mm, allows for easier fitting of windows and doors
Reliable and dependable weather tightness
Works in temperatures from -40°C up to 65°C
An Optional Corner Guard is easy to install and increases
protection to framing
Scope of Use / Applications
Windows/Door/Timber & Steel Frame Flashings
Masons 40 Below™ Flashing Tape and Masons Corner Guard must be installed in accordance with these instructions.
Ensure the 40 Below™ Tape completely covers the joinery opening.
To ensure maximum adhesion of the tape, make sure the substrate surface is clean, dry and free from any dust or other contaminants. Flaps are folded into the opening and secured.
The building wrap is installed as shown to the exterior face of the frame. At window and door openings it is cut on a 45˚ angle away from each corner, then the flaps are folded into the opening and secured.
40 Below™ Flashing Tape must not be stretched. When joining 2 sections of tape,
overlap by 100mm or more.
Compatible with most building sealants, check suitability with sealant manufactures.Alternatively do a patch test before use.
RIGID AIR BARRIERS – 40 Below™ is tested and approved for sealing the joints on Rigid barriers. Tested and approved for use with BGC Durrabarrier and OS’BraceRAP.
TRADIES: Please check stock availability with your store
MERCHANTS: To inquire about this product or to place an order please contact your Account Manager.
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