How can I protect partially buried deck posts from decay?

Question

I poured concrete footings for my deck. I put the galvanized post base and the 4x4 post on it. Now I need to raise the ground/dirt level as water puddles there. But if I raise the ground it will cover the footing, post base and a few inches of the post. I'm concerned the dirt will decay the post. Can someone recommend a solution?

I was thinking of wrapping the post somehow or maybe cut the post and pour more concrete over the existing footing but afraid it will not hold up.

I already have a deck. It's a pool deck about 8x20 attached to another deck that is 20x25 which is attached to the house. The pool deck has 9 footings, enough that it can be freestanding but I attached it to the existing deck. I'd need to raise 5 of the nine footings about 4-6 inches. They are the footing near the pool not the rear ones near where deck is attached to other deck.

I can leave the post base which is bolted into the footing and add a few rebar pieces, put a form around and pour concrete with bonding adhesive http://www.homedepot.com/p/SikaLatex-1-Gal-Concrete-Bonding-Adhesive-and-Acrylic-Fortifier-187782/202521398. Sound reasonable? Would I just drill a few holes for the rebar pieces, maybe 4-6 inches deep? Should the holes be wider than rebar to get some fresh concrete around them?

Answer 1

Check the tag on the end of your posts, see if it says it is rated for ground contact. If so, you're fine. The post base simply keeps it out of standing water. If it says above ground, you are still probably fine. That post will last longer than you'll enjoy your deck. Honestly, that worthless little post base will rust away before the post rots. I've repaired that issue far more than I've repaired rotted posts. Modern engineering does not concern itself with longevity.

However, if you feel compelled to address the issue, use a heavy-rated automotive jack rated for 5-10 tons+. You can very easily jack up each post a few inches to do whatever you feel you have to do. Don't bother with the commonly-available floor jack you have in your garage, they are typically only rated for 2 tons, and will fail.

My advice is fill around each post with larger-sized gravel for drainage, backfill as necessary, and forget it.

Answer 2

The correct way to do it would be to pour a new concrete base to raise it up. Make sure to tie the new concrete you pour into the old concrete. But, I would probably just use a rubberized coating (either spray or roller) to coat both the wood and the metal and then fill in around it with dirt. This should last for a long time, maybe even longer than the rest of the deck.