Deck frame: cedar vs. steel
I am interested in opinions on whether northern white cedar is a good material to use for a deck frame. I’ve heard opinions that it actually lasts longer than pressure treated pine, but also doubts about using it structurally. I would protect the tops of the joists with some kind of flashing, as that seems to be where wood decks rot, and upsize the joists as called for in structural tables for the lower strength.
The case in point: we are planning a simple 12×12 deck and had been planning on avoiding PT by using a steel frame from Trex and cedar decking. The idea was that the decking might decay before the occupants of the house do, but that frame would last longer, and it would be reasonably easy to replace the decking without replacing the frame. But, partly motivated by the slow process of getting the steel frame parts properly specified (working with a distributor who apparently doesn’t deal with them much), I am wondering whether I should consider doing the frame in cedar too. We can buy cedar from a local mill in Vermont for very reasonable prices, so it would certainly be cheaper than the steel frame.
It probably comes down to the steel frame being more expensive and likely to last longer, and we’ll simply have to weigh durability vs. cost, but if someone has a strong opinion or relevant experience they are willing to share I’d appreciate it.
Fortunately, we don’t need to tie the deck to the house at all–we have four piers to put it on and plan to have a ~1 inch gap between it and the house, so we can avoid the challenges of thermal bridging and water intrusion associated with a ledger.