Oriented strand board (OSB) is durable, reliable, and long lasting. But like all wood products, if left exposed to weather for extended periods of time OSB is susceptible to expansion and contraction associated with moisture absorption and drying; wood that expands and contracts will change dimensions. In addition, wood strands on unprotected surfaces of OSB may become raised, which is aesthetically displeasing though not a structural deficiency.
OSB is resilient enough for exposure during a normal cycle of construction, but should be protected during storage to ensure it doesn’t weather prior to installation. Follow these tips to keep panels unblemished during storage and delivery:
At the Yard
• Keep OSB under cover in a completely enclosed warehouse, if possible, but at minimum under roof cover.
• Store OSB panels in a flat orientation.
• Keep side covers in place to protect the tongue-and-groove edges.
• OSB transported on open flatbed trucks should be covered with a weatherproof tarp.
• Handle panels in a flat orientation. Protect edges and ends from damage and keep the load level.
• When moving OSB with a forklift, stack on a bunk or a pallet and insert the forklift tines in between the supports, not into the panel or sheathing stack. Be sure to get the tines under the load to avoid spearing it and damaging it.
• Unload the pallet of OSB all at once with a forklift; if the stack is unstrapped and the truck jerks forward, panels could fall and ends could be damaged.
At the Jobsite
• Schedule shipments to ensure OSB isn’t exposed to weather on site for long periods of time.
• Do not store panels in direct contact with the ground or mud. Store OSB elevated on three 4x4s, one in the center and the others 12 inches from each end. This will keep the wood off the wet ground as well as allow for ventilation.
• For flooring panels, wait to remove cardboard side covers until ready to install to protect the tongue-and-groove edges.
• Minimize moisture exposure for OSB panels and all wood framing in the home by getting the home roofed and wrapped in a timely manner.
Following these simple steps, in conjunction with proper 1/8-inch panel gapping and good construction practices, can help ensure your OSB sheathing and flooring installs accurately, smoothly and beautifully. For additional strategies and advice, contact your manufacturer’s representative.