A builder specifies the use of a self-adhered membrane (SAM) as the weather-resistive barrier (WRB) on a plywood sheathing substrate. What critical preparatory step must be explicitly followed before applying the SAM to ensure proper adhesion and performance, especially in colder temperatures?

Question: A builder specifies the use of a self-adhered membrane (SAM) as the weather-resistive barrier (WRB) on a plywood sheathing substrate. What critical preparatory step must be explicitly followed before applying the SAM to ensure proper adhesion and performance, especially in colder temperatures?

Answer options:

• Applying a continuous bead of construction adhesive to the sheathing. ✅ Priming the plywood surface with a compatible primer.
• Wetting the plywood surface to reduce dust.
• Heating the SAM with a torch for increased tackiness.

Correct answer: Priming the plywood surface with a compatible primer.

Explanation: Most self-adhered membranes require a compatible primer applied to the substrate, such as plywood, to ensure maximum adhesion and performance, particularly in various temperature conditions or when the substrate might be dusty or porous. Applying construction adhesive or wetting the surface are incorrect for SAMs, and torching can damage the membrane.