Sealing outdoor plywood keeps it from rotting and peeling and reduces its chances of mold and mildew. A water-resistant sealer takes only a few minutes to apply but needs to dry for several days. Plan for this drying time. Plywood is a flexible wood material with a variety of uses, from simple household projects to major construction tasks.

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If your skin comes in contact with the sealer, wash the affected area immediately.

Step 1

Set the plywood on the drop cloth. Put on the gloves.

Step 2

Wipe any dust from the plywood with a rag.

Step 3

Dip the paintbrush in the sealer. Brush the sealer onto the plywood, starting with the edges and moving inward to the surface.

Step 4

Let the treated plywood dry for three days.