Wood planks used for a deck can bow and warp over time from continuous exposure to the elements. Lower quality lumber, such as treated wood products, are especially susceptible to bowing caused from natural shrinkage. However, it's possible to straighten bowed wood planks by following a few simple tips.
Make Use of Tools in Your Arsenal
Fine Home Building, a handyman repair website, says a warped deck plank is straightened with the aid of a pry bar and a pipe clamp. The website recommends inserting the short end of the pry bar in the opening between the installed boards so that the long end of the tool points to the board you're installing. From there, fasten the pipe clamp's tail stop on top of the pry bar, and secure the clamp's head to the work piece. Turn the crank a couple of times until the board is straight.
One tried and true method for straightening bowed wood decking is using the proper tools, such as the Bowjack. The Bowjack works to straighten bowed wood by applying leverage much like an automobile jack. Kelvin Broderson, the tool's designer, claims the Bowjack is strong enough to straighten a warped plank up to 2 1/4 inches with a forward pull of the jack handle. Bowjack works in conjunction with a sharp spur that penetrates into a joist (or similar device) to hold the board in place as leverage is applied to straighten the wood.
Control Moisture and Add Weights
Moisture causes a deck to warp. Paint Source, a painting and home improvement information source, recommends limiting the amount of moisture that comes in contact with a wood deck by periodically coating it using a water-repellent sealer. However, moisture combined with weights is an effective method for straightening bowed woods when the damage is minimal. Saturate the board and place weights, like concrete blocks, on top of the wood. Keep the weights on the wood until the boards have a chance to thoroughly dry out. It's traditionally a preventive measure to keep straight wood with too much moisture from warping, but it can help straighten bowed wood decking as well.