Flashing grade adhesives are typically used to bond membrane flashings to vertical substrates. Which option best reflects this statement?

Flashing grade adhesives are typically used to bond membrane flashings to vertical substrates. Which option best reflects this statement?

• A. Vertical substrates
• B. Horizontal substrates
• C. Concrete
• D. Wood

Answer: (A)

Flashing grade adhesives are chosen for their ability to grab and hold membranes to upright surfaces, where gravity could make a membrane sag before the adhesive cures. Bonding to vertical substrates—such as walls or parapets—ensures a secure, watertight seal around flashings at edges and penetrations. The statement specifically calls out vertical substrates, so the best reflection is the idea of bonding to upright surfaces rather than to horizontal planes or to particular materials.

Flashing grade adhesives are chosen for their ability to grab and hold membranes to upright surfaces, where gravity could make a membrane sag before the adhesive cures. Bonding to vertical substrates—such as walls or parapets—ensures a secure, watertight seal around flashings at edges and penetrations. The statement specifically calls out vertical substrates, so the best reflection is the idea of bonding to upright surfaces rather than to horizontal planes or to particular materials.