PLYWOOD VS. OSB
A Homeowner's Guide
Building a house? You'll find that different builders provide varying quotes, often opting either for OSB sheets or plywood in their budgets. Wondering which to choose? Here's your guide to understanding these materials and making an informed decision for your new home.
The Basics of Plywood and OSB
During the rough framing phase, both plywood and OSB play critical roles. They cover subfloor joists, exterior walls, and roof trusses, essentially holding your house's structure together. Both materials are recognized by building codes for their structural integrity and strength. However, they differ slightly in performance, which could influence your choice.
How They're Made
Plywood layers and press angles.
Plywood is manufactured by layering thin wood veneers, which are glued and pressed together at high temperatures. This process creates a strong and resilient wood panel.
OSB (Oriented Strand Board), on the other hand, involves pressing together small, cross-oriented rectangular wood pieces. This engineered wood panel also showcases impressive strength, but with different characteristics.
OSB manufacturing by pressing wood pieces.
Key Differences: Water Resistance and Durability
A major difference between plywood and OSB is how they handle water exposure. Plywood tends to be more water-resistant over time, even in extreme climates. It swells when wet but generally returns to its original size after drying. OSB, however, is more susceptible to moisture and water penetration, especially around its edges, which might weaken its structural integrity when exposed to harsh weather conditions for prolonged periods.
Construction Considerations
The framing phase for a typical single-family home (2,000-3,000 sq ft) can last about 4-6 weeks. During this time, your building materials are likely to face a few rain showers. Both plywood and OSB are engineered to withstand this without losing structural strength, but quick framing is crucial. The faster you get the roof and siding up, the better protected your structure will be from the elements.
Extended exposure to rain, frost, and sun can degrade both materials, particularly around board edges and nailing areas. UV radiation can also affect the adhesive qualities of the glue used in OSB or plywood.
Choosing the Right Material for Your Project
In drier, summer conditions, OSB is a great, cost-effective choice for subfloors and wall sheeting—it's typically about 15% cheaper than plywood. However, if construction is set during the rainy season or winter, opting for plywood might be wiser to avoid potential moisture issues.
For projects shielded from the elements (like additions under an existing roof), OSB offers the same strength as plywood at a more economical price point.
Ask Your Builder
When discussing materials with your builder, consider the seasonal climate during your construction phase and the specific uses of plywood or OSB in your structure (or even Zip System Sheets). These considerations will help ensure that you choose the most suitable material for your home.