Concrete pier - Moved!

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DMouse Canada
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Concrete pier - Moved!

#1

Post by DMouse »


Hi, I recently discovered my shed had moved enough to push against the concrete pier. This was causing the mounts alignment to keep going out of whack. It drove me nuts for months, till I discovered what was causing it. Basically the shed is built on a slope. It drops about 8 inches per 10 linear feet. Anyway the shed had sunk about 2 inches on the downhill side, and the roof opener had walked the shed downhill enough to push against the concrete pier.
I am in the process of rebuilding the shed. I checked the concrete pier to see if it was vertical, and left to right its fine, but it is leaning about one quarter inch downhill, measured at the top.
The question being should I add more support or now that the shed is no longer pushing it, it will settle and should be fine?
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Re: Concrete pier - Moved!

#2

Post by helicon »


You may be able to move the pier slightly with a hydraulic jack. It kind of depends on the how deep the concrete was poured. I have dealt with some concrete issues recently. In my garage the center of the concrete is rising due to some underground tree roots that keep growing and pushing up the floor. Had to use a jackhammer to remove the high spots and resurface it. Kind of a temporary fix, but hopefully it will last for a few years.
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Re: Concrete pier - Moved!

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Post by Gordon »


When I poured my pier at my former residence. I dug a 3 foot hole surrounded by a 3' x 3' square.
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Then I sunk a 6 foot post in the middle of the hole and poured a concrete pad with 4 rebar supports for the pier.
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After a couple days to harden I poured the pier itself.
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It was rock solid. However this was in southern California so we don't have a lot of cold weather or rain to worry about. The additional support for the surrounding area of the pier might help if you are willing to redo what you have.
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Re: Concrete pier - Moved!

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Post by UlteriorModem »


Wouldn't it be prudent to cut a gap around the pier? So that nothing is pressing against it?
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Re: Concrete pier - Moved!

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Post by pakarinen »


I might be way off base here, but I think you should consider repouring the pier. Sounds to me like the downhill forces might come back to haunt you. And it's not like you have to slab jack a house foundation. ;)
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Re: Concrete pier - Moved!

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Post by DMouse »


UlteriorModem wrote: Wed Oct 21, 2020 5:13 pm Wouldn't it be prudent to cut a gap around the pier? So that nothing is pressing against it?
There was a gap! The shed moved! I think the garage door opener I use for the roof walked the shed. I plan on leaving a lot bigger gap this time, and put a floating cover around the pier to cover it. I also plan on changing the roof opener from a chain drive to a belt drive as the belt version has a soft close/open action.
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Re: Concrete pier - Moved!

#7

Post by Micke187 »


how big is the concrete slab underneith for the pier? In mine i poured almost 1 cubic meter concrete in 1.3meter deep and 0.7meter wide . Havent moved an mm for 5 years :) And also had a idea when i built mine if and that was a big "if" to place a flagpole there if i would give up on this hobby. That wont happen so.. Thats why i made mine that large :) So for future proof make the concreteslab larger. The bigger the sturdier!
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Re: Concrete pier - Moved!

#8

Post by seigell »


DMouse wrote: Wed Oct 21, 2020 12:11 am The question being should I add more support or now that the shed is no longer pushing it, it will settle and should be fine?
  1. Don't work to lever the Pier back into its original position; only the Plate needs to be level (a function of the Leveling Bolts). Also, any progress made to right the Pier will only further unsettle the ground in which it originally sat; and likely will leave a gap into which it will settle again.
  2. Dig and Pour Footers in the New Slab to be poured. These should be of decent size and depth (no need to go as deep as the Pier - but enough to provide substantial purchase into the Subsoil. Dig them on both the uphill and downhill edges, but leave a couple gaps in at least the downhill Footers to allow any subsurface water to drain.
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