Choosing a Material for Porch Flooring
I am preparing to replace the floor of a client’s covered front porch here in Massachusetts. They want painted tongue-and-groove wood, like their existing floor. I’m told by a local carpenter friend and the local lumberyard that what is typically used around here for this purpose is 1×4 tongue-and-groove clear vertical grain Douglas fir.
I can’t find a lot of information about installing a porch floor out of that material, including in the GBA encyclopedia entry on porches and decks. So, a few questions:
Is there a different/better material I should consider for a painted, tongue-and-groove front porch? (They do not want to use one of the tropical hardwoods.)
Will the Douglas fir be strong enough to support people without bounce and sag, without a plywood subfloor? The existing floor is 5/4 fir, and likely old growth stuff. What I can find is 3/4″ thick, and I’m concerned it won’t be strong enough.
Is today’s Douglas fir, once painted, likely to be rot resistant enough for a covered porch, at least for 10 years or so?
Do I need to treat the wood with borate or something else, or can I just prime it on six sides?
Thanks for any info on this subject.
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