The traditional method of attaching a deck ledger is to drive 1/2-in. galvanized lag screws following a fastening schedule from the building code. Doing that job right means pre-drilling the holes, and then reaming the outer portion of the holes to fit the unthreaded portion of the lags. And then you’d have to place a washer over each lag and drive it home. That’s three steps for each lag. Few people do, or even know about, all these steps. Available for only a few years now, structural screws provide a much simpler and faster option. No predrilling is required: You simply sock the screw down with an impact driver. As with lags though, there’s a little more to know than what’s on the surface. Like lags, structural screws must be installed according to a schedule, but in this case one provided by the manufacturer. Likewise, they must fall within a specified distance from both the edges of the ledger and the edges of the band joist to which the ledger is being attached.
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The cross-section illustration in the video shows the screw tips stopping shy of the inside face of the house rim board. Though this is permissible from Simpson Strongtie's standpoint the building code and code officials generally require that screw tips extend through the rim board so the building official can inspect that the screws have made sufficient penetration.