Hello XXXXXX XXX,

Welcome to Just Answer.

Sorry to hear about your problem.

It sounds like you are saying that the existing wood post is rotted. If this is the case, you can simply replace the wood post by temporarily supporting the deck with a car jack and some cmu blocks or wood timbers. If the existing wood post was encased with a concrete footing, then it will be hard to replace it. I would pour a new concrete footing next to it with a new pressure treated wood post and Simpson metal connectors, as you mentioned. The old concrete pier can stay in, but I would remove the rotted post to prevent attracting termites, etc.

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Best of Luck, Brian

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XXXXXX XXX,

I understand now. You do not have to pour a concrete pier to match the existing one and you can pour a footing next to it, as you mentioned. A pressure treated 6x6 will be adequate and use the Simpson connectors; "post base" at bottom and "post to beam" for the top. The footing should be at least the diameter of the existing pier or at least 8 inches; 10 inches would work great with a 6x6. Insert one or two pieces of #4 rebar in the footing to minimize cracking and insert a "J" anchor bolt at the top to fasten the post base to. Dig the footing hole below the frost depth in your area and pour the concrete on undisturbed soil and some crushed stone, to minimize settling.

If you need further help or clarification on this answer, please do not hesitate to reply to this post.

Thanks for asking your question at Just Answer.

Best of Luck, Brian

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