DURAFORM® forms are manufactured using plywood that was rated by the American Plywood Engineers as being the optimum configuration for concrete forming applications. Our plywood is 1 1/8" 11 Ply Structural I Douglas Fir with a High Density Overlay. The obvious advantage of our system is the cost. An average DURAFORM® set usually costs less than half of the price of an aluminum set. Accessories are also significantly less. The DURAFORM® System is also easier to set windows and vents. With the DURAFORM System, you need only one grade of form release agent over the entire life-span of the form. With aluminum, various grades are required over the life span of the forms.