The fasteners must be installed with the heads flush to the panel surface. If overdriving occurs, no more than 20 percent of the fasteners are permitted to be overdriven more than 1/16 inch (1.6 mm). It is recommended that where nail heads occasionally are more than 1/16 inch below the surface, an additional nail should be provided between existing nails. If a over 20 percent of the nails are overdriven, the panel should be rated at the difference between the thickness and the over driven depth. If the panel does not meet the required shear capacity then the sheathing should be removed and the framing checked for splitting before replacing the sheathing with proper nailing.