I just finished pouring concrete pier/post under an existing porch column. It leans. The form was off plumb by 1 1/4″ over its 4 ft of height. This is a 10″ x 10″ column of concrete. Do you think that this is going to be a problem that I ought to fix now?
It sits atop a footer that is 16″ x 16″ x 9″ thick. I made an error on the footer too. I centered that in the wrong spot. So the concrete pier runs to the edge of it instead of being centered on the footer.
Replies
Got a sledge hammer? Or do you not need that much support?
PAHS Designer/Builder- Bury it!
Are you serious. I mean that the pier shouldnt be used?
I could build another alongside it.
Are you serious
Not completely. You've compromised the strength. It's under a column. Minimal footing. If you don't need much support, you've got it. From your description, impossible to tell.PAHS Designer/Builder- Bury it!
I don't need much support. I was overdoing the pier and footer in terms of strength to prevent even the possibilty of future movement. I messed up and now have a huge problem. The porch isn't even 42" wide. It is attached to the house as a continuation of the roofline. 16" of the pier extends above the soil, the rest is buried.
Bury it and carry on, it will always be the reminder that some of us need to double check everything before we pour. my 2 cents Rik
Sounds like you have it so over-engineered now, that you can just consider this one "pre-settled" and carry on with your backfill. But tamp it tight so it doesn't lean any more.
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
You'd better believe i will backfill this one carefully but I hadnt considered that I should tamp the backfill too. I will now.
From what you describe, you have a hunk of concrete that weighs maybe 550 - 600 pounds sticking up out of a hole in the ground. If it's not too deep, and you take great care with bracing, perhaps you could dig out to make room for it to go where it should be, shove it over to the right place, and straighten it up. Then fill around and under the bottom with slurry to get good bearing. The weight you're dealing with is well within the range of simple levers, or at most a small bottle jack. If the existing structure is in the way, the jack will be the easy way to go.
Work carefully, as my liability is limited to what you paid for this advice. ;-)
-- J.S.
shove it over to the right place, and straighten it up.
As Piffin said, I've "over-engineered" the thing. I cannot straighten the column because it is interconnected with the footer with rebar. Trying to raise the edge of the footer and then shore that up is beyond my capabilities.
So now I have 7 cu ft of concrete that I see from the responses here has the definate potential of becoming a problem. I think that what I'll do is build some kind of footer and pier close to this one, a lot less imposing in size, to have as an emergency pier to use in case the main one fails. Thanks everyone for the input.
Edited 8/1/2005 7:08 pm ET by Cleveland_Ed
Consider the error for what it is, no big deal as the footing is larger than necessary for such a small porch.Go ahead and finish up the porch.
mike
well I'm going to stick myself out to be critized, as you have goofed, but here you are asking for help and you are to be commended to care enough to ask. there will be those who will have a tendancy to rip you for doing a shoddy job....personally I would hate to see anything that much out of plumb and same goes for the pad.
......however - going only by the info provided I will guess that the porch is not that heavy a load. heavier loads require bigger pads. There are times when pads are not used for decks/porches; holes are sometimes dug and the sona tube is merely stuck in the ground without a pad. these holes are not always perfectly plumb. I could easly see a hole being out of plumb as much as what you have. The earth around the poured cloumn will keep the column in place.
when you back fill you will get the same effect. which is more than you can say for the leaning tower of pisa....and well, so far it's still up.
as far as the pad goes. It's good to have the post centered but it can be off. as far as being off as much as yours is, you may be fine, but it would personally bother me too much to leave it like that. I would have moved the pad when I placed the 10x10 column form.
since it is too late for that you can very easily make the pad bigger. add some form boards to the one side of the pad drill some holes in the pad, epoxy in some rebar dowels to tie things together and throw some concrete in.
I think if you were to at least do that, you will feel better about the whole thing.
anyways..that's just my opinion
So extend the footer, tieing it to the current footer with epoxied rebar. That is definately less work than just ignoring what I have done and building a new footer and pier adjacent to it. And yes, I would feel better about it to do something now if there is any possibility of this pier leaning further.
The rule-of-thumb is that loads have to go through the middle third of a column. Outside of that middle third is a cantilever off of the column which creates a moment arm to upset the column.
So, technically, as long as the deck above lands in the middle 3 1/3" (that's really only 1 5/8" either side of the center), it's "ok."
That's in a perfect world, too; and I'm not an engineer, just a poster on the internet . . .
The real question is will your sense of craft/skill/competence "tollerate" the "uh oh"? If it's your own deck, that could be maybe.
If it's eating at you now, it will likely eat at you later. I'll guess it would be much easier to fix right now than later, too.
Me, I've pulled down set concrete (my own and others') because I wanted it right. But, that's me, others differ.
The rule-of-thumb is that loads have to go through the middle third of a column. Outside of that middle third is a cantilever off of the column which creates a moment arm to upset the column
The load is on the outside third, and that is the direction of lean. So I've made another potentially serious error.
Ed....now that I've got a clearer picture of what you have I will somewhat stand by what I said earlier. As piffin stated it is over engineered for what you have and I agree with that. However you also, now have stated that the post is on the outer edge of the leaned side.
One verrry nice thing that you have going for you is that it sounds like your pier is square as opposed to a round sona tube. with your square post it will be surpriseingly easy to remedy the situation!
Do not go to the trouble of making a whole new pad and post. I believe that will be a waste of time. alter the pad and post that you have already. extend the pad as I explained earlier. also drill some holes in the same side of the post and stick some short dowels in there. then take some 3/4 ply and drill some 3/16" holes to attach ply to existing post with a 3" common nail and tie wire looped over so that the 2 ends of wire will stick into the hole this will hold the nail in tight when you hammer it in, and you will still be able to pull it out with a nail puller when you go to strip ( you can use a duplex nail as well, but the ones we have here have a larger diameter and don't always work well with the tie wire. with your 2 side of ply attached you can now fasten a bulk head to the open end.
You can even angle the bulk head the opposite way to counter act the lean, and maybe even make it look like you planned it that way.( nothing like making a mistake look like something that is not.) basically you will end up with a post that is tapered bothways. you will be happy and it probably took longer for me explain than it will take to do....beats building a brand new right beside your old you to point out the mistake.
Ed, since yer kind of stuck with what you have unless you break it all out and start over...
Just dig down beside the whole thing. Pour in more concrete to match the dark green. Bury it. (Backfill with gravel, tamp, all the usual stuff. I'm not getting real complicated here...) And yer done. No one will even see it.
Or, if you are concerned what that post/pier is going to look like in the future, you can additionally pour the light green on top, to match the existing pier.
I am making the assumption that you know to drill the existing and epoxy in some rebar, etc....
Are we there yet ?