In order to better understand how to comply with this standard, it is important to define the role of flashings. Flashings are fixed to a building’s barrier against the elements before installing windows. Flashings prevent water from penetrating horizontal joints, which redirects water outside. For flashings to be effective, they must
Acceptable Impermeability According to the Standard
The main feature of a flashing is its impermeability. In this regard, the standard clearly defines what is considered an acceptable flashing. Acceptable flashing materials include reinforced bitumen and rigid metal containing aluminum, copper, galvanized metal, or other factory-conditioned non-ferrous metals.
RESISTO has the right product to conform to CSA A440.4-07: the REDZONE 25 membrane. This self-adhesive membrane, which ensures sealing around doors and windows, is made of reinforced elastomer bitumen and tri-laminated woven polyethylene. Once installed as a flashing at the bottom of the window or door, the REDZONE 25 membrane eliminates drafts and water infiltration. It seals the edges of the anchors that pass through windows or doors, ensuring compliance with CSA Standard A440.4-07. For even more optimal waterproofing, it is best to also apply REDZONE 25 to the top flashing.