What is the minimum nominal thickness for plywood used in common formwork systems in construction?

The minimum nominal thickness for plywood used in common formwork systems is typically set at 3/4 inch. This thickness provides the necessary strength and rigidity to support concrete loads during the curing process while reducing the chances of deflection or warping. Plywood of this thickness is also advantageous as it strikes a balance between weight and structural integrity, making it easier to handle on construction sites without compromising its performance.

Using thinner plywood, such as 1/2 inch, generally does not offer the required load capacity and stability needed in formwork applications. As a result, it may lead to bending or failure under the weight of freshly poured concrete. On the other hand, options like 1 inch and 1.5 inches exceed the necessary specifications for most common formwork situations, making them less practical in terms of weight and cost efficiency. Therefore, 3/4 inch is recognized as the standard thickness that meets both structural needs and practicality in formwork systems.