Background: 22 foot long, six foot wide, four foot high porch on a Victorian house. Decking will be 1×4 T&G fir, running across the width. Current joists (running lengthways) are rough 2×6 redwood, with greatest span seven feet, on more or less two foot centers.
I’m upping the joists to 16 inch centers for good support of the decking.
The optimum spacing of the girders running across the width uses the girders to tie major studs (under the porch pillars) to the house, but results in a span of eight feet for the joists, which, according to the span tables I’ve seen, exceeds recommended span for Douglas fir 2×6.
At last, my question: I’m considering also upping the joists to 2×8, due to the increased span. Good idea or overkill?
Replies
Now this is just me talking, the king of overbuilt and over budget but if space allowed, I'd use 2 x 10s or even 2 x 12s. Who knows when someone will want to sit that huge stone table or heavy Adirondack (sp?) chair on it?
Cost difference of a 2 x 8 to a 2 x 10 is not all that much and I think the extra strength is worth it.
Mike
I`m with Mike...2 x 8 would be minimal, and only if there was a need to keep them that small. 2 x 10 would be my preference and definetly center on 16 inches. Todays lumber doesn`t have the beef it once did.
J. D. Reynolds
Home Improvements
"DO IT RIGHT, DO IT ONCE"
It's a mistake to run t&g with the length. It should run away from the house to facilitate runoff or water will colect in the joints and rot the decking more quickly.
Actually, I am running the decking away from the house -- in line with the pitch (1/4 inch per foot, code standard and, strangely, what it was pitched before -- one of the few occasions this house has been code). Thanks for the thought, though. I agree that running it paralle to the house would be a big mysteak.
IMHO 1/4" / ft is a lot of pitch for a porch deck.T. Jeffery Clarke
Quidvis Recte Factum Quamvis Humile Praeclarum