Simpson’s SDWF structural wood screw is designed to span floor framing and connect the upper and lower walls within the continuous uplift load path of the structure. It features a unique take-up washer that installs over the upper floor’s sole plate and self-tightens to take up the slack if the structural components shrink. According to Simpson, the SDWF is capable of compensating for as much as 3/4 inch of shrinkage per story. It’s code-listed and available in three lengths to fit joist widths ranging from 91/4 inches to 18 inches. Prices average about $6 per piece.
Simpson Strong-Tie, 800/999-5099, strongtie.com/fasten.