So one corner of my deck is sinking! It's a second story deck. I got a jack and a support pole and I have the corner up level, but the 4x8 post that goes into the ground, goes into a huge slab of concrete that they obviously poured around the post when they built the house/deck. I can't get around the chunck of concrete due to the patio and I don't see another way to get under the post and fill in the dead space to keep it raised up. My plan was to dig from the side and fill in under the post while the jack supported the deck.

Any other bright ideas? I have no idea how deep it goes into that chuck of concrete, but I'm certain there's not enough room to remove the post and fill in the dead space.

I wish I wasn't half the home DIY guy as I am a gearhead!

 

What part of the country are you in? That will dictate how deep the concrete should have been poured to act as a proper footing for the deck.

How much has it dropped over how much time?

If it hasn't moved too much, I might be inclined to cut the existing post off at the concrete and simply install one of those metal post anchors (you can get them in the joist hanger section of Lowe's) on top of the footing and just replace the existing post with one that is long enough to support the deck at level. The nice thing about this is that if it drops some more, you can simply remove the new post and install another longer one -- make the post-to-anchor connections with screws instead of nails to make any future repair easier!

FYI -- this is the "shade tree method" to avoid what you should probably really do -- remove the post, concrete pier, and replace with properly dug and installed new assemblies. A MUCH BIGGER JOB........

 

Here's a link to the type of anchor I'm thinking: https://www.google.com/search?q=meta...Sl8DXsQgjYIzwM

 

Got enough room to get sand under it? Like they say, sand gets into everything. Also, sand is a low Plastcity Index type material. It doesn't change its physical volume due to water like a clay soil and water literally runs right thru it providing great drainage.

 

Perhaps dig until you get to the bottom of the concrete. Bust it up with a sledge hammer. Dig deeper and pour much more concrete than it had originally both in circumference and depth.

 

That corner/post has sunk a good 6" over six years. It's the result of a rushed job with that section of the yard that has sunk/settled. Had to have a retaining wall put in on a creek bank and a section behind the wall (encompassing that one post) has settled to the point it needs work. The post itself didn't sink, the concrete foundation of the post sunk, and took the post (and deck obviously) with it. Jacking it up to level was no problem. Due to the patio surrounding three sides of the post, I have no idea how I'd ever get under there, much less to break it up and get it out of there. Not a job I would undertake (but that's mainly because I HATE yard work, LOL). I don't think that anchor will work as the post (4x8 I think) is not completely surrounded by the concrete patio. I'll get some pics up.

After looking at it also, I'm making an assumption that the post does NOT protrude through the bottom of the concrete chunck, thus no easy way to fill that in. So no, no easy way to get anything in there to fill the space under the post once it's jacked back up to level.