Reader Questions Bolting Ledgers to Studs

At the end of Glenn Mathewson's "Handling Lateral Loads" (January/February 2012), he proposes connecting a 2x12 ledger one step down from a door threshold (something many of us in snow-country regularly do). He suggests attaching the 2x12 ledger with lag screws (he calls them lag bolts) into the house rim joist and structural screws driven into the wall plate and into the studs.

I've thought about using a ledger-mounting detail similar to the one Glenn describes but wasn't sure if structural screws or lag screws could be driven directly into studs and plates or how the edge distances to fasteners would come into play.

First I mapped out the location of the ledger and fastener locations based on the IRC 2012 figures so I could wrap my head around the detail. What I found is that at the lowest possible ledger position, the screws driven into the studs would be 2 1/4 inches or less down from the top.

Then I inquired with technical reps from FastenMaster and Simpson Strong-Tie about using their structural screws for attaching ledgers directly into wall studs or plates. FastenMaster doesn't have any published information for driving its screws into narrow members for ledger connections, but I did get a qualified "maybe." Deck builders can contact them for instructions based on the conditions of each individual installation.

Simpson Strong-Tie does have a detail showing its SDS screws mounting a ledger directly to wall studs (strongtie.com/products/connectors/SDS.asp), but a footnote indicates that the minimum end distance is 3 inches. So it looks like a user who wants to install a ledger as Glenn proposes would have to contact Simpson for guidance.

One of the concerns both company reps noted is the possibility of the screws being off-center of the stud or plate. Driving the screws precisely straight into the studs and plates so the fasteners achieve the greatest holding power is important. As soon as a screw drifts toward the edge of the wood, it doesn't hold as well. And then there is the risk of splitting the stud or plate. Unless a deck ledger is mounted during construction and before the interior finishes are applied, it will be nearly impossible to inspect whether the fasteners hit their mark or miss their mark. So even though I thought the idea was good initially, I'm not so sure I would trust it.

Mike Guertin
East Greenwich, R.I.

From the Forums at DeckMagazine.com:

Laying Out Porch Boards

I plan to use 5/4 x 6 ipe on an 8-foot-by-35-foot covered front porch. The joists are 16 inches on-center and run perpendicular to the house, so the deck boards will run parallel to the house. What length boards would you order for the best look and to minimize waste? Should I go with all 16-footers or a mix of lengths?

Posted by Bruford

I would run the decking on a 45-degree angle to avoid any butt seams. The 5/4 ipe can span 16-inch joist spacing at 45 degrees. This would be a bit more expensive, but the angled decking makes the deck feel bigger. At an angle, 12-foot-long decking would just cover the 8-foot depth.

If you didn't want the angled decking, I would split the deck into three 11-foot-4-inch sections and run two seam boards perpendicular to the decking. You would have to lay out the joists for the seam boards and add blocking to support them.

If you want to keep the decking parallel to the house and don't like seam boards, I would use 16-foot, 12-foot, and 8-foot boards and stagger the seams. There are lots of different ways to do it.

Posted by Bayn Wood