Cody Johnson

Time-tested, versatile performers, plywood structural panels have been a staple in home construction for more than 70 years. From roof decks to subfloors and wall sheathing, plywood’s strength, stiffness, resistance to moisture, tight grip on nails and screws, and ability to be pressure treated make it a solid choice.

Strength and Stiffness
Southern Yellow Pine – used to make such plywood panels as SmartCore Rated Sheathing (for roofs, walls and subfloors) and SmartCore Sturd-I-Floor underlayment from RoyOMartin – is one of the strongest and stiffest woods grown in North America. That means solid, quiet floors and roofs that can stand up to some of Mother Nature’s worst.

The stiffness of a plywood subfloor or underlayment minimizes deflection between the joists when the floor is walked upon. That helps prevent a soft, “spongy” feel underfoot as well as those annoying squeaks and creaks. It also helps keep hard flooring surfaces, such as tile, from cracking.

In areas with heavy snow loads, plywood roof decks have the necessary strength. “When you’ll have two feet of snow sitting on top your house for a part of the year, plywood can handle the weight,” said Chris Harris, a buyer of Southern Yellow Pine plywood for UFP Purchasing Inc.

Cody Johnson
Cody Johnson

Moisture Tolerance
In a perfect world, structural panels – regardless of type – would not be exposed to the elements. But despite home builders’ best efforts to keep them dry, panels are frequently subjected to rain, snow and high atmospheric humidity before a home is fully buttoned up. It’s simply unavoidable. And when they get wet, they swell.

If panels used for a subfloor or underlayment remain swollen, they can telegraph through the floor covering above. Using plywood panels, such as SmartCore Rated Sheathing and SmartCore Sturd-I-Floor, can help prevent this.

“Plywood is more tolerant of moisture. It’s more forgiving,” Harris said, explaining that the panels will return to their nominal thickness as they dry, helping ensure an even finish floor.

Cody Johnson

A Tight Grip
In hurricane zones, a plywood roof deck can enhance a home’s resiliency. Plywood holds on tight to nails and screws, helping keep roof sheathing and roofing materials anchored in place in high winds.

Resistance to Insects, Rot and Decay
Southern Yellow Pine plywood also can be chemically pressure treated to resist insects and fungi, Harris noted. Treated panels are a wise choice for wall sheathing, roof decks and subfloors in areas where these structural elements must be protected from mold, mildew and destructive pests.

For more than 70 years, home builders and their clients have turned to plywood structural panels for quiet, solid floors with no telegraphing through the finish floor, roofs that can take the weight, and the ability to repel bugs and rot.

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