Need advise on how properly to correct a structural settling problem. 25 year old home on a crawl space with a 40 foot built up center beam — 3 – 2×10’s which were suppose to set on 3 seperate concrete block center supports. Mason left the block stack one block short so the “carpenter???” stacked multiple 2×4’s ( on their side), one on another to make up the difference of the missing block and metal shims. The last and top 2x was rippened in half to make the final elevation. Over the past few years I’ve noticed that a center non load bearing wall in the house has started to pull away from the ceiling. While I am not 100% sure, I feel that the 3 stacks of 2×4’s supporting the center beam have compressed enough to allow the beam to settle about 1/4 inch. I have yet to strech a line along the low side of the beam to confirm this —– but I suspect I will find this to be the cause. Now my question: I know I have to stop the settling but am concerned about trying to correct the 1/4″ of settling. Given the settling has happend over many years, is it possible to correct the bow in the beam without having it’s ends raise up and cause more and new dammage at the gable end walls—- like breaking windows or doors that will no longer open or close. The ends of the beam are set into the block foundation on metal plates and off cource have not settled any. How would it work if I was to set 3 new screw jack beam poles on the conrete pads next to the exisiting concrete blocks and start raising the screw jacks a little each month and keep raising them—- over a year or so, until the beam, floor joises and floor is back to it’s original elevation???? My original idea was to use one hydraulic jack and some blocks to raise each support enough to remove the wood blocks and replace this with structural metal of approriate height—- but realized this would probably tend to also raise the ends of the beam. COMMENTS??? SUGGESTIONS ?????
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If after you string line the beam to confirm your theory you find that it is leave the string there.
Try jacking each point in turn just a bit and reshimming, work from one end to the other and watch the effect, I bet you can level it out no problem. The settling may well be the pier pads themselves
With only a quarter inch or even a half, there is no problem jacking it back up and adding shims to tighten things up.
It is also possible that the sight you see at top of wall is related to truss lift, so do confirm straight line on beam before starting jacking.
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Haro;d, I took the liberty of breaking you post down into smaller paragraphs to help with the readability of your question.
By the way, Welcome to Breaktime.
Cheers
Need advise on how properly to correct a structural settling problem. 25 year old home on a crawl space with a 40 foot built up center beam -- 3 - 2x10's which were suppose to set on 3 seperate concrete block center supports.
Mason left the block stack one block short so the "carpenter???" stacked multiple 2x4's ( on their side), one on another to make up the difference of the missing block and metal shims.
The last and top 2x was rippened in half to make the final elevation.
Over the past few years I've noticed that a center non load bearing wall in the house has started to pull away from the ceiling.
While I am not 100% sure, I feel that the 3 stacks of 2x4's supporting the center beam have compressed enough to allow the beam to settle about 1/4 inch.
I have yet to strech a line along the low side of the beam to confirm this ----- but I suspect I will find this to be the cause.
Now my question: I know I have to stop the settling but am concerned about trying to correct the 1/4" of settling.
Given the settling has happend over many years, is it possible to correct the bow in the beam without having it's ends raise up and cause more and new dammage at the gable end walls---- like breaking windows or doors that will no longer open or close.
The ends of the beam are set into the block foundation on metal plates and off cource have not settled any.
How would it work if I was to set 3 new screw jack beam poles on the conrete pads next to the exisiting concrete blocks and start raising the screw jacks a little each month and keep raising them---- over a year or so, until the beam, floor joises and floor is back to it's original elevation????
My original idea was to use one hydraulic jack and some blocks to raise each support enough to remove the wood blocks and replace this with structural metal of approriate height---- but realized this would probably tend to also raise the ends of the beam. COMMENTS??? SUGGESTIONS ?????
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damn, am I fat!
1/4 inch isn't much at all.
Jack slowly, over the course of a week or so (you don't need a year), and you should be OK, if it's only 1/4 inch. (In fact, you can probably just get away with jacking 1/4" in one go, but 1/16 to 1/8" is a better limit.) You can go faster in humid weather, slower when it's dry.
(Actually, I'm guessing, if you can notice the sag, it's closer to a half-inch or 3/4, meaning you'll want to jack over 2-3 weeks.)
When you make the permanent fix, take your time to be sure that any new concrete footers are done right. You need to dig down at least to solid undisturbed soil. But the existing supports are probably fine (they've already settled if they were going to). Maybe just use some concrete brick (and mortar) to bring them up to within about 2 inches of the beam, put down sill seal membrane, then a piece of treated and shims as needed. (Also, if you're in termite territory, it's not at all dumb to add some termite barriers.)
When I jack to straighten, I rarely take less than a quarter inch a day.
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Your original construction was probably off by more than 1/4" in more than one direction prior to the beam support being placed.
The first thing to do is pull that string or we're guessing. You may have to lower the darn thing--for all we know it was placed too high to begin with.
There's a good chance that some blocks were thrown down and there was poor contact with the ground, which has since settled in so you may have lost as much as 1/2" in height there.
Unfortunately, the foundation walls are probably as likely source of uneven settling. Running a water level around the perimeter of the crawlspace will be an eye opener. No, don't do that before the holidays in case that 1' of secret/covered up overdig that wasn't compacted very well has come back to haunt you.
Likewise, Piffin is right on the money with repect to truss uplift causing the wall problems.
Happy Holidays!
Beer was created so carpenters wouldn't rule the world.
If you have access to one, you might want to check it with a laser.
Heck, they're so cheap now, it'd be silly not to get one just for this one-off job.
People never lie so much as before an election, during a war, or after a hunt. --Otto von Bismarck
Maybe - but I don't have much use for cheap tools.
Well, then the OP should buy an expensive one, then give it to you when he's done.
People never lie so much as before an election, during a war, or after a hunt. --Otto von Bismarck
Level in this case may well be less important than straight.
Go crazy trying to jack to level if the two ends aren't to start with.
Not to question the ability of the original concrete and framing crews and all.
You are right, a string line would be fine for this.