Metal Roofing Directly On Plywood

Metal roofing can be installed directly onto plywood decking to create a durable, long-lasting roof proper fasteners and underlayment should be used to prevent issues like condensation buildup or roof leaks that could damage the plywood over time. Metal roofs stand tough against weathering. Their sleek look graces buildings worldwide. Installing them involves key choices. One is whether laying metal roofing straight atop plywood can work. If done right, the roof will endure. If wrong, trouble looms. Plywood offers an affordable and simple decking option. Yet moisture sits atop non-breathable wood. Trapped water causes rot. Also, plywood lacks robustness for heavy roofing. Still, with careful sealing and quality fasteners, metal applied directly on plywood can perform.

Protective Underlayment Be Applied Over The Plywood Before Installing Metal Roofing

To ensure a sturdy base for metal roofing, use plywood with a thickness of at least 1/2 inch. This provides ample support for the roofing material and helps prevent sagging or warping over time. Securely fasten the plywood to the roof rafters or trusses to ensure stability and durability.

Once the plywood is in place, install a suitable underlayment such as roofing felt or synthetic material. This additional layer helps protect against moisture and enhances the roof’s weatherproofing. With the proper plywood thickness and underlayment, you can proceed to install the metal roofing panels according to the manufacturer’s instructions, ensuring a reliable and long-lasting roofing system for your home or building.

Potential Problems Of Not Using Underlayment For Metal Roofing

Not using underlayment with metal roofing invites trouble. Skipping this step risks moisture seeping through. Without underlayment, water can penetrate the plywood. This leads to rot and damage over time. Underlayment acts as an extra barrier. It shields against wind-driven rain and snow. Without it, leaks become more likely. In essence, underlayment protects your investment. It’s a crucial layer for a sturdy, long-lasting roof.

Plywood Purlins Under Metal Roofing

When choosing between plywood and purlins for under metal roofing, it’s essential to consider the structure’s stability. Plywood provides a solid base for the metal sheets, ensuring a secure installation. Purlins, on the other hand, are horizontal beams that offer support for the roofing but may require additional materials for proper attachment. Plywood offers versatility and ease of installation, making it a popular choice for residential roofing projects. Purlins, though sturdy, may require more labor and materials to install correctly. Ultimately, the decision between plywood and purlins depends on factors such as budget, building design, and local building codes.

Frequently Asked Questions

Should I Put Anything Under A Metal Roof? When installing a metal roof, use plywood as a solid base and add underlayment for moisture protection. Flashing and trim are also crucial for durability and weather resistance. Can Metal Roofing Be Installed Without Sheathing? No, metal roofing needs sheathing for support and protection. Skipping it risks leaks and structural issues. Follow proper installation guidelines for a strong roof. Do You Need Wood Under Metal Roof? Yes, you need wood under a metal roof. Plywood provides a sturdy base for installation and prevents moisture issues. Underlayment adds extra protection against leaks.


Installing metal roofs directly onto plywood can work well. It presents challenges though. Moisture and durability issues must be addressed. With careful installation and quality materials, roofs will last decades. Pay attention to details like underlayment and fastener type. Plywood requires extra care for metal roofing. But it offers affordability and availability. Correct construction techniques can make plywood decks robust and long-lasting. A quality metal roof on plywood will protect buildings for years. With informed decisions, metal and plywood can partner to deliver durable shelter.