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Build strong, long-lasting outdoor projects with durable treated lumber. Specially pressure-treated to resist rot, decay, and insect damage, this lumber is ideal for decks, fences, landscaping, and other exterior structures exposed to the elements. We carry a wide range of sizes and dimensions to suit everything from structural framing to finishing details, ensuring stability and performance in Canada’s diverse climates. Whether you're building a new deck, replacing fence posts, or tackling a custom backyard project, treated lumber provides the strength and reliability you need. As a proudly Canadian company with locally owned stores, Windsor Plywood offers hard-to-find building materials and expert advice to help you get the job done right. Visit your local store to explore our selection of treated lumber and start planning your next outdoor project with confidence.
Frequently Asked Questions
What types of pressure-treated lumber does Windsor Plywood carry?
Windsor Plywood carries pressure-treated SPF and pine lumber in standard framing dimensions including 2x4, 2x6, 4x4, 4x6, and larger post sizes, as well as decking boards and plywood. Treatment ratings range from above-ground use to ground contact and permanent wood foundation applications, each suited to different levels of moisture and soil exposure.
What do the treatment retention levels mean on pressure-treated lumber?
Treatment retention levels indicate the amount of preservative per cubic foot of wood and determine where the lumber can safely be used. UC2 is for interior damp use. UC3B is for above-ground exterior exposure. UC4A and UC4B are for ground contact applications like fence posts and deck footings. Always match the retention level to the application.
Is modern pressure-treated lumber safe for vegetable gardens and children's play structures?
Yes. Since 2004, residential pressure-treated lumber in Canada has used copper-based preservatives that replaced the older arsenic-containing CCA treatment. Current treatments are considered safe for vegetable garden beds and play structures when the lumber is fully dry. Let newly treated lumber dry for several weeks before placing it in a vegetable bed.
What fasteners should I use with pressure-treated lumber?
Use hot-dipped galvanized, stainless steel, or fasteners specifically rated for use with treated lumber. The copper in modern preservatives reacts with standard zinc-plated and electroplated fasteners, causing rapid corrosion. Hardware including joist hangers and post bases must also be rated for use with treated lumber.
Can pressure-treated lumber be painted or stained?
Yes, but wait until the lumber is fully dry before applying any finish. New pressure-treated lumber often has residual moisture from the treatment process that prevents paint and stain from adhering properly. Test dryness by sprinkling water on the surface — if the water beads, it is still too wet. Once dry, apply a quality exterior primer and paint, or a penetrating exterior stain.