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Bob visits the Georgia Pacific plywood plant near Savannah, GA to see how Birch veneer plywood is made. Most of the products made in the GP plant originate from resources in North America. First the Birch veneers are graded into face or back. The internal layers are made of actually made of Yellow Poplar. Each of the layers in the plywood has its grains cross-laminated, which adds strength. They are then put together on a glue spreader and using urea formaldehyde glue stuck together (The glue is specially formulated to contain only a small amount of formaldehyde) GP uses both heat and pressure to bond the layers and then uses precision saws and giant sanders to insure the boards exactly 4� by 8� and smooth.

Bob takes a tour of the American Plywood Association testing facilities with Tom Williamson, the Executive Vice President of Engineered Wood Systems. Tom explains the various wood tests to Bob. First is the gluelam tester that tests the large beam with two load heads that apply up to two hundred fifty thousand pounds of pressure to the beam. The beam breaks at thirty-two thousand pounds of load. Next, Tom shows Bob the cyclic shearwall test which pushes an OSB wall and framing system back and forth to simulate an earthquake and measures the amount of load the can be applied to it. Tom then leads Bob to the panel flexure test, which determines the bending stiffness and strength of an OSB panel. Another test simulates a plywood window shutter by shooting a two by four into it with an air cannon. Finally Tom shows Bob the buckling wall test that exposes a plywood sidewall to three weeks of continuous rain and then measures how much it has buckled and moved. After three weeks, the wall has moved less than one tenth of an inch.

Bob introduces Reggie Ray from Georgia-Pacific to discuss the laying of the sub-floor with southern yellow pine tongue-and-groove plywood. He discusses some of the advantages to using plywood over OSB, including fewer squeaks.

Bob visits the visits the Simpson Plywood plant in Shelton, WA where Jim Langenberg shows Bob how plywood and especially MDO is made.

General contractor Kevin Kalman and carpenter Bob Ryley lay plywood to the soffit of the front porch ceiling in the Mt. Pleasant house in Charleston, South Carolina.

Bob confers with carpenter Bob Ryley and general contractor Kevin Kalman as they lay down the subflooring at the Mt. Pleasant house in Charleston, South Carolina.

Bob meets Lisa Francis of the APA on the front porch of the Habitat for Humanity house to watch the installation of the MDO being used for the outdoor space's ceiling.