So the wizards that built my house put the support columns in my basement directly on the poured concrete floor. No footings.
I own a couple of Jack posts from the local Home Depot (I think 10k range). However, as I started to jack up the beam, it moved ever so slightly, but most of the work was going into deforming the metal plate that has a detent for the jack screw. First set of questions: do I need better/bigger equipment or just more 10k jack posts? I had screwed the metal plate to a 2×8 scrap – was that a mistake?
Second question: I pulled a string line down the beam and I can see that the beam has fallen just over 1″ in the middle. However the curve isn’t uniform. The beam actually falls within about 5′ of each end and then is basically straight in the middle 20′ or so. Will this beam straighten out as I jack it? I realize I have to go slow, and since I live here it’s no problem. I can do a 1/4 turn/day if I have to.
Here are the all the facts I can think of concerning the beam:
I beam is 12.5″ tall with a 5″ flange (not sure what the weight per foot is – couldn’t find it on the beam). The I beam total length is 33′ with two intermediate support columns. One is 12.5 feet from the end, the other is 11 feet from the end, leaving about 8.5 feet between the two columns. House is a ranch, so just one story above the beam (though I contemplating a second story addition). Floor is 2×8 ,16″ oc, spanning about 14′ to each exterior wall, with 1×6 plank subfloor and 3/4″ oak floor. The beam also carries various 2×4 walls with 1/2 drywall and a ceiling with 3/8″ drywall (yeah, it sagged too), and 2×6, 16 oc, ceiling joists. Best I can tell, the interior walls don’t carry much of roof load – most of that goes to the exterior walls all of which are fine.
Replies
From your description of the beam I can't tell what size it is. W12x14's-W12x22's have 4" wide flanges. W12x26's - W12x35's have 6 1/2" wide flanges. Could you have a true "I" beam? These are designated as "S" shapes. Looking at the end view of the beam the flanges have a slope on the underside of the flange. Depending on flange and web thicknesses it could be a S12x31.8 or an S12x35. Maybe this is a used beam that was picked up at a salvage yard and installed in the house without regard to load, span, etc. It just looked like it would hold everything. If a used beam, it could have been bent when installed. Sounds like a job for an engineer. Jacking these things always scares me. Usually what you don't want to move, moves.
Dana
Salmon Falls Housewrights
DJ.. made the right call first, this was likely a salvage beam from an industrial site with severe load on catilevered 5 ft end section, as evidenced by the posters quote:
" has fallen just over 1" in the middle. However the curve isn't uniform. The beam actually falls within about 5' of each end and then is basically straight in the middle 20' or so." A residential load with no big loads (as stated) above those points would bend a beam like that.
No way a 10 kip jack is going to straighten the 5 ft ends without some serious torch work (NOT recommended to a novice without first doing it on a scrap sample or having some some serious heavy machinery bending/repair experience) Even with a bigger, better jack, expect lots of plaster cracks upstairs, and a ;;h;ump in the middle if the end get straight.
I had the same thought but hesitated to mentionit because of two things. One is the fact that he wants a second story which will require some engineering analysis anyway. The second is that theree could be a lot of compounding issues and he is a DIY who may not be avle to keep everything on track. Could cause more problems than he fixes. besides, these builders may have used a crooked beam and then shimmed to it already. That is worth being sure of to start.
A twenty ton jack might be better too. The eight would be working right at the max and could blow a seal. ( You don't know how much it hurt me to typr that phrase)
;).
Excellence is its own reward!
Joists are definitely not already shimmed to the beam. All floor joists are riding right on the beam.
There is currently a design on the table which I support of adding a second story over another part of the house and then later, just demoing the beam side of the house and rebuilding it, at which time I could easily correct this beam issue. Once all the first floor walls came off, those floor joists would be easy to move or maybe even just get rid of the beam and put in a flush (wood) beam with the floor hung off that.
Well we'll see what the architects come up with in the end...
Thanks for all the help and keep it coming! I'm going to be posting here a lot as this remodel gets swinging into gear. Also, as for being a DIY, yes I am. But I think you'll find I have a pretty solid skill set. I read FHB and FWW and all the taunton books I can find. I buy quality tools (well...except for that damn PC framing nailer - I just borrow the BIL Hitachi gun). I've also had several friends ask me to remodel their house.
Thanks again folks and take care.
Well, Axe, Keep'm coming then. Be glad to help out.
Cedar shims will be just fine unless you are going three or four stories. The 2x8 compressed because it was all in one place but spread out over (under really0 each joist every 16". it won't be that bad..
Excellence is its own reward!
Some thing is sorely amiss here just not sure what. (that nagging feeling)
Joist directly on the beam. Where is the plate?
The beam is sagging. Was it heated / warmed at some time? Dropped? Sprung? Overloaded in a former life? Generally abused? When it was installed a 1" deflection (or any part there of) would have had to been addressed at that time. Doesn't sound as though it was. This leaves the possibility that it didn't exsist at the time of installation. (being used has been suggested)
No footers and.... Seems as though this house got off to a bad start. What is the upstairs like? You can cut only so many corners before just about every thing is compromised. (cringe)
Bite the bullet and change the beam. Add footers. Lots of work but in the long run perhaps that would be the best move. The mention of a second floor and all. The HO said he wanted to raise each individual joist and shim. What's the ripple effect going to do with / to the integrity of the structure upstairs. 1" is a long ways.
There must be doors in that house that don't work right or stick. If they do work OK now they must have been reworked. And...... That 1" has got to transmit clear to the ridge and there must be some seriuos latteral stresses.
"Best way" seems to be the order of the day and not what some one "might" get away with.
Who ever invented work didn't know how to fish....
Wow,
When I saw your name I was expecting another funny one-liner about the seal. This is the longest post I think I have seen you write. The fingers and brain are both firing on all ten cylinders this morning.
Very well presented arguement. It's kind of what was nagging me in back of my mind way back in the thread when i said I was leery of recommending too much to a DIY who mioght not be able to see and understand all the symptoms on site.
But an inch in lumber framing over a storey and a half is not all that much if spread out enough. I've jacked worse without much crackling going on.
That whole diagnosis of how and why it came to be this way is telling us something though. Time for an experienced engineer. Since architects are involved, they should be on top of this thing but it sounds like they ducked it..
Excellence is its own reward!
I jacked a few houses too, but never 1 joist at a time. Everything at once, over the entier length required, as uniform as possible over a lenth of time w/o being in a hurry.
Who ever invented work didn't know how to fish....
I think we totally agree and are just chasing each others ideas around in circles without acctually seeing the job..
Excellence is its own reward!
I don't necessarily think the architects have ducked it. They said "it definitely needs to be fixed.". That was at our first meeting at my house. They are coming back next week with some ideas for us to look at. I'll pin them down more on the beam at that time. I'll ask them if they can engineer it or can recommend someone to look at it.
I'm a "do it right the first time" kind of guy. So if that means I have to spend lots of time pooring footings and getting rid of the beam so be it. I'll get it done and get it done correctly and safely.
It appears to just be common sense to me that concrete floor was the original failure point. I don't know if the concrete slab was not supported correctly or if the slab couldn't take the weight of the columns. Either way, the result is the same. I also know that the basement had water issues in it's life (since been fixed), so it's possible water worked it's way under the slab and undermined it (yikes).
Fortunately most of doors on the first floor run parallel to the beam. And are all in the middle section that is basically level, so all the doors work for the most part. I really got in tune with the problem though when I replaced the doors to my bedroom closet (52" wide RO). The floor fell 3/4" across that RO and obviously wasn't ideal. So I really started measuring what I long suspected. Ever since I moved here, if I push around too hard on my office chair I can get going "downhill" and slam into my desk. I just hadn't done any evaluation of the issue until recently.
It's hard to tell if the sagging is affecting the roof or not. The roof wasn't framed all that well so it doesn't look great (it's probably coming off anyway). The roof is 4-12, stick framed, 2x6 ceiling and roof (house is 27' feet wide in this section). About 1/3 of the way down from the ridge, a 2x4 was run the length of the roof on the underside of the roof rafters and then about every 4' a 2x4 jack was run from the roof 2x4 to the interior wall (over the beam). Problem is those 2x4 jacks have a pretty steep angle (probably about an 8-12 pitch or so), so I can't see them supporting diddly-do for roof weight. And then I have two layers of asphault shingles up there, so the weight is just piling up. BIL (professional framer) recommended putting supports from the interior wall up to the ridge to make the ridge carry more weight.
About the only thing I can see that was done right was all my floors were framed with 2x10 SYP ( I originally said 2x8, but I spoke before measuring). And blocking was installed at the midpoint of each span. And this blocking was done by some kind of trim carpenter or something because that stuff is tight fitting. Floor has no bounce at all.
Thanks for all the help. I'm contemplating a digital camera so maybe I'll post some pictures soon. I know that would help.
I'm telling ya, it's just tartar sauce. Really.
yur gonna get jacked right off this thread refering to that old penguin and Bill C joke<G>
"A twenty ton jack might be better too. The eight would be working right at the max and could blow a seal."
Ignoring the possible humorous side of that statement (Which is difficult) I'd rather see the guy use one of those big screw jacks.
Screwing is better than blowing.........................a seal.I've never seen a monument erected to a pessimist [Paul Harvey]
Nice...
Groan... : )Any jackass can kick down a barn, but it takes a carpenter to build one.
I doubt any posts you bought from HD are going to hold 10,000#.
If you've got a beam sagging that much, someone needs to take a look at the situation. No way we can diagnose it from here.
The Constitution of most of our states (and of the United States) asserts that all power is inherent in the people; that they may exercise it by themselves; that it is their right and duty to be at all times armed [Thomas Jefferson]
It sounded to me like a W1235 which I wouldn't use for more than about a twenty foot span or so but you have even less free span than that. It seems to be failing at the supports. Some deflection would be acceptable but an inch sounds excessive. Whether you can ever get the "crown" out of it is debatable and could be an expensive experiment.
The adjustable jack posts you have are NOT for lifting a house or for straightening a steel beam. They are for holding a weight once it is in position. The 2x8 block is another mistake. You are penetrating it with a force of hundreds of thousands of PSI. If you continye with the steel posts, be absolutely certain that they are plumb and that the top is fastened to the steel beam or you could see it skid out and kick somebody in the head hard enough to open it up. Spot welding or at least clamping the cap plate to the beam is one way to deal with that.
The source of the problem might be the lack of footing as you adressed originally. Footings are not always necessarily separate. A pad can be a thickened spot in the crete floor with rebar crossing through it. The soils under also have an effect. Who knows what was done back then?
I too, believe you need to pay an engineer to assit you with this, all the more so if you are thinking of doubling the load with another storey.
Excellence is its own reward!
Thanks all for the responses.
In regards to having a true Ibeam - "looking at the end view of the beam the flanges have a slope on the underside of the flange" - Yes I believe I do have this. The top and bottom flanges thicken by 1/2" or so from the edges to the web.
Another thing I didn't clearly state is that my basement floor is cracked parallel to the beam (not directly under it, but about a foot to one side). It's been like that for the three years I've owned the house, so it's obviously stable. But the second story is obviously going to change that.
A "can do" DIY solution for you would be to leave the steel beam in place, jack the individual joists to a straight string level line and shim to the beam. With just a 8 ft span, that 12" I beam aint gonna bend past what it already was when installed. You may want to support near the posts, then dig out under the posts and pour in a few more cubic feet of concrete a few weeks before you do this.
Your HD screw jack would probably do the joist/jacking, but a good plumb 4x4 and cheap $20 8 ton hydraulic jack from Harbor freight or Northern would be a lot easier on you.
Junkhound has the answer, just jack and shim each joist seperately. I did something like this last year. I cut a 4x4 post with a plywood cleat at top for clamping to joist. Then placed ten ton hydraulic jack with a 3/8" thick piece of steel under post ( without the steel the jack would push into the post bottom). Jack joist to a line and shim.I would place a piece of plank under the jack to spread the load. I imagine the beam was bent when it was installed.
mike
I'd thought about the jacking up the floor joists approach too. Certainly a more manageable project and since I'm redoing the whole space above it I can just crack walls and whatever, I don't care.
What is recommended for shims? I assume normal cedar shims would get crushed over time. I was thinking about making my own shims with MDF. I have a tablesaw and bandsaw sitting right there in the basement so I could easily make up just about anything out of wood. I wonder what the compressive strength of MDF is (quick web search didn't turn up anything)? Must be pretty high given that it weighs almost as much as concrete. At each joist I'll be bearing on 15 sq in (5" wide beam and 2 overlapped 2x floor joists), so if the compressive strength of MDF is 500 lbs/sq in, that is 7500 lbs on each joist. Not likely to be anywhere near that.
Should I jack each one up a little bit at a time and just keep going back over them until they all come into line? I think I'll find it hard to move one joist 1" with the one just to the right or left not moved at all.
I used a combination of plywood, 1/4" to 3/4" and 1/8" masonite. I jacked each joist , one at a time. No problems jacking with 10 ton jack. The situation I was in was far worse than yours. I was hired to trim out a brand new house that the owner had framed .When I arrived I installed stairs, entrance doors etc. The house was ready for sheetrock when I noticed a big problem. Standing in the large kitchen I looked up and saw the engineered joistswere sagging big time. I couldn't believe what I saw. I strung a line and used 2x4's for gauge blocks. The worst joists were sagging 1 7/8",there were two like that . The rest of the joists were succeedingly less until I got to the outside wall. After talking to the owner I got him to call the truss company to talk to their engineer. In meantime, I shored the ceiling down to the floor. Luckily bearing beams were almost directly under my shoring. Turns out the homeowner had reversed a number of joists, not upside down but end for end. The joists are the 2x4 on the flat web truss type. They were engineered specificly for this house. Second floor exterior walls did not line up directly over walls below, they sat several feet in, thus the joists were made to take the load the walls normally would do.
The engineer gave me a drawing to fix this mess. After jacking each joists I clad each side of joist with 3/4" sheathing. This did the trick. I jacked each joist about 3/16" higher than my line, allowing for deflection. This worked great, ceiling has no dips.
In your case, it seems like a simple job. You may want to consult an architect or engineer . If you will definitely add a second story, then make sure you get one or the other.
Do not use mdf, crumbles easy under weight. Plywood masonite or any wood rip to thickness will be fine. Cedar shims are fine, they might compress, but it would be negligible.You may have to renail floor if you jack one at a time, but I doubt it.You could jack each joists a little at a time. You will need more framing lumber to hold joists temperarily while you move jack to next one. I did not see any nail popping in the house mentioned above.
Mike
Edited 9/11/2003 8:54:08 PM ET by MIKEK4244
Because you are planning a 2nd story, you're going to need professional advice anyway. So take this into account. However, if you do put in footings and intermediate support for the beam, I agree with the individual joist alignment, but would use 2 steel wedges over one another, driven from each side. Any fabrication shop can make them for you.
As said before, something doesn't sound right here. Assuming S12x31.8, A36 steel (min yield 36 ksi, but usually quite a bit higher), I=218in^4, S=36.4in^3, my napkin doodles show that for a 1" elastic deflection over 5' of cantilevered beam (you said it was straight except for 5' at the ends), you'd need over 90,000 lb of vertical force at the end of the beam. The beam would have long since gone plastic (permanently bent) at something over 25,000 lb at the end (could be much higher, depending on actual yield strength, plus it could actually be a heavier section beam).
I suppose you could come up with a loading that would concentrate load at about 5' from each end, with some distributed load between the columns to keep the beam from deflecting upward at the middle of it's span (are there large column loads 5' from the ends?), coupled with sinking column footings, but in the end, that beam is permanently distorted, and no amount of jacking is going to make it go away. That doesn't mean the beam is unusable (bridge beams are deliberately crowned so that the addition of other steel and concrete decking in the field deflects them into the desired profile), but a work-around plan is a job for an engineer or architect skilled in such unusual problems. If you could completely unload it, you would know what shape it's really in, and come up with a plan to use it, but you still wouldn't know what condition the footings are in. As posited above, it may be better to replace the whole system, beam, columns and footings, as part of the overall reno and expansion plan.
Either it was distorted when installed, or it became distorted from the loading and/or poor support. But just to look at it, that's a damn big beam to suffer that much distortion in such a short span due to house dead and live load. Hire an engineer, and perhaps consult with a good contractor who works on old problem houses. And if you go that way, I'd also suggest you get them talking to each other early and often.
Edit: Missed the part where you have an architect on-board already. Carry on.
Be seeing you...
Edited 9/12/2003 11:19:27 AM ET by Tom Kanzler
The beam is loaded evenly and only supporting a normal first floor above with only a small part of the roof load, if that.
If the concrete floor failed in the middle of the span under the two columns, that would leave only the two end points of the beam supporting the entire floor. That span is ~35'. My *guess* is that 1" deflection under such circumstances would be the minimum I would get. Tom - can you do a rough calc on what would happen on a 35' span? Now obviously the columns and the center 25' of the span have fallen 1" and there is some weight on the columns now, so the beam isn't spanning 35'. The more I think about it all, I'm wondering if something didn't undermine the concrete slab (like water or a rotting stump) and that started the whole failure process. It's all very interesting. I can tell you that my basement floor has a crack right down the middle and falls about 1.5" from foundation to the crack. Just unclear at this time what drove the failure.
My feel is that I'll never be able to jack a 1" crown of such a monster beam, so my options are to shim the floor on top of the beam, or replace the beam. Both are doable.
And just to really send you guys into a tailspin the beam also has a 2-3" horizontal sway in it . When I pull a string line down the length of it the center of beam is 2-3" farther away from the string in the middle then it is on the ends. My guess is that was original, but you never know. The previous owner might have run a car dealership upstairs or something, who knows.
I'll certianly come back and update the thread when I get some kind of solid data points.
And just to really send you guys into a tailspin the beam also has a 2-3" horizontal sway in it
( )( )( )( )( )( )( )( )( )#/
If you had said that earlier it would have prevented speculation...It is definately a salvaged beam. The 1" vertical deflection is there to stay. Your yield strength is reduced; no way to tell how much. Get it out of there and start off right--good footings, good beam, good engineering--before you start to build off it.
also has a 2-3" horizontal sway in it -- loved Sam's tailspin<G>
I thought? somebody took some stuff out of my scrap pile ? You don't live near me do you?
Pop and Grandpa both worked for the railroad (1907-1977 inclusive) The'd bring home old salvage beams that had been rolled in the 1890s for railroad structures. Usually the structures (overpasses, bridges over creeks, etc) were torn down with a railroad wrecker, sounds like your beam just a 'little' "bent outa shape" .
They used to 'fix' them with a big fire of railroad ties (no EPA) a couple's friends with old cars, put the hot beam against a few old ties up against a tree and pull with chains on the cars to straighten. I'm sure glad I'm not THAT poor anymore.