I am building a garage extension, 10′ x 14′. The original is sheathed with 3/4″ cedar (I think) shiplap siding and nothing else (no ply, etc.). It is probably 60-70 years old.
I am putting on pine 3/4″ shiplap siding, because it was the only thing I could find that matches the existing profile (#106 or 107, coved at the top, sometimes called “specialty”). But the pine seems pretty floppy.
I wasn’t planning on sheathing with ply or OSB, but now I am wondering if that is a bad choice. The pine probably has enough tensile strength, but its lack of stiffness worries me.
Should I sheath first even though the original is just sided?
One other question: I am planning on using 8 penny galvanized box nails to hold the siding (instead of finish nails that were used on the original). Any thoughts on that?
Thanks, and happy holidays to all.
Replies
I personally prefer double wall construction, especially if you're going to insulate. The only time I see siding put right to the studs (over a vapor barrier) is on economical tract-type construction. But then, I tend to overbuild a little in other areas too.
I'd probably use galvanized 8d casing nails myself, but then, I live in a sometimes damp climate.
Jules Quaver for President 2004
In answer to your question, i believe that siding over studs was an inexpensive alternative to the old dilema of whether or not sheathing and wood siding should go against each other. The thought was that the two back to back would cause moisture buildup and premature aging of the exterior siding and rot from the inside out. It was thought better to have the siding simply as an outside protection on the outside of the studding. The existing garage should have let in bracing at all four corners for stability against wind and the loads of the structure itself. As far as nails are concerned, I would use a galvanized splitless siding nail. They are a little more costly but have less chance of splitting the board when nailed close to corners or an end of a board where a butt joint would meet on a stud. I guess then... that whether you need sheathing is a matter of matching the new siding with the old and if you have let in bracing in the new structure.
MERRY CHRISTMAS AND GOOD LUCK!
JACK OF ALL TRADES (AKA) PATTERSON RENOVATION