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Homeowner Forum / Construction / August 2005I-beam installed upside down
Hi everyone. A year after living in our newly constructed ranch house we noticed that the floors were separating from the floor molding in one area of our house. It turns out that one of the posts holding one the the I-beams was loose causing it to sag AND the I-beam was installed upside down. The builder put new posts in and have been cranking on them to get the I-beam straight. My question is: Is it ok for the I-beam to be turned upside down. I thought that the manufacturer pre-bends them so they are level when a load is applied. These types of errors *can* be quite dangerous. In one case, a square shaped main beam was installed sideways in a hotel. Well it was very strong when installed the proper way, but quite weak when installed sideways - it collapsed. I would contact the manufacturer of the I-beam and ask to be sure. <bstewart68@hotmail.com> wrote in message > Hi everyone. A year after living in our newly constructed ranch house > we noticed that the floors were separating from the floor molding in [quoted text clipped - 8 lines] > thought that the manufacturer pre-bends them so they are level when a > load is applied. Thanks for the info > Hi everyone. A year after living in our newly constructed ranch house > we noticed that the floors were separating from the floor molding in [quoted text clipped - 8 lines] > thought that the manufacturer pre-bends them so they are level when a > load is applied. Only if it is a specific-application beam will that be true. If it was just a standard I, they're just straight stock. I'd be surprised if it were anything else unless it is a very custom-design home. OP- How long is the beam? What size is the beam? How often supported & span between supports? Was it really cambered (pre-bent) to account for dead load? Seems unlikely for a typical residential application Are you sure it was installed upside down? w/o seeing the installation it's kinda hard to tell, but jacking to level seems ok. Unless we're talking about a lot of sag. cheers Bob This is not a custom home. The house is 40' wide. And I don't know for sure about the camber. The beam travels the width of the house. There are two posts equally supporting the beam. I am not sure the size, I will need to measure. I spoke to the company that installed the beam. They said it would not matter which side it was installed. I think the builder is feeding me a line of #$@*. So then if the I-beam is ok, should it be level when properly installed? I can look down the lenght of the beam and there still looks to be some sag compared to the other beam. Thanks > This is not a custom home. The house is 40' wide. And I don't know > for sure about the camber. The beam travels the width of the house. > There are two posts equally supporting the beam. .... I gather that means two intermediate posts as well as the end supports. If so, you have roughly 13-14' free span, I presume? > ... I am not sure the > size, I will need to measure. I spoke to the company that installed > the beam. They said it would not matter which side it was installed. > I think the builder is feeding me a line of #$@*. So do I... > So then if the I-beam is ok, should it be level when properly > installed? I can look down the lenght of the beam and there still > looks to be some sag compared to the other beam. Yep....if the area is open between the ends just stretch a stringline taut between the two ends along the top side of the lower flange...it'll give you a good visual indication. How likely is there to be some deformation as a result of the missing support? TB > How likely is there to be some deformation as a result of the missing > support? > TB Guess you'll find out...no way to guesstimate from afar w/ no actual load data, beam sizes, etc., ... > Hi everyone. A year after living in our newly constructed ranch house > we noticed that the floors were separating from the floor molding in [quoted text clipped - 8 lines] > thought that the manufacturer pre-bends them so they are level when a > load is applied. Unless the beam is cambered there is no top or bottom to an I beam. It could be installed sideways. __ I I is your beam placed thusly, the correct way, or I-----I thusly, the wrong way? _I_ This would make it an H-beam wouldn't it? he he he... Bryan "The Monk" Chaisone > Hi everyone. A year after living in our newly constructed ranch house > we noticed that the floors were separating from the floor molding in [quoted text clipped - 8 lines] > thought that the manufacturer pre-bends them so they are level when a > load is applied. Is this a steel I beam or a wooden I beam? there is no upside on I beams. Sometimes beams are cambered to carry the dead load and some live load. If your beams were precambered, it may be they are upside down. If they were sized too small, I would say they have sagged.!!!!!! Thank you for the many responses. I hope I answer everyones questions...If you need pictures let me know. I was told by the builder that the I beam was installed upside down (by the steel company) in addition to one of the support post being faulty. I just assumed that there would be a camber if it was important that the beam was to be a certain way. it is NOT installed like this: |--|. The dimensions of the beam are ~40 ft long x 8 1/4 ft. high x 5 1/4 ft. width. I ran a string along the length of the steel beam. There is 3/8" sag in the middle . So it sounds like the builder needs to lengthen the posts some more. The two intermediate posts are installed ~13 ft apart. BTW: The Ohio Home Builders Association states the floor should be level for 3/8"over 32" length. What size beam was specified on the plans? If they were your plans, you (or the structural engineer / Architect) are ultimately responsible if the beam is undersized. You are putting WAY to much faith in your builder, and he taking on WAY to much liability if he sized the beam and the locations of the columns. His statement about the beam being installed upside down reinforces my point. Builders are just that. Builders. Many do a great job of building what is on the plans, and many screw up to a point of building something dangerous when they start "cowboy engineering". just my .02 S. > Thank you for the many responses. I hope I answer everyones > questions...If you need pictures let me know. [quoted text clipped - 11 lines] > BTW: The Ohio Home Builders Association states the floor should be > level for 3/8"over 32" length. Wow, give em a break on the install Based on your dimensions, That beam was probably very heavy. > Thank you for the many responses. I hope I answer everyones > questions...If you need pictures let me know. [quoted text clipped - 11 lines] > BTW: The Ohio Home Builders Association states the floor should be > level for 3/8"over 32" length. If you can't recover anything from the builder - why not buy a couple of those screw jacks - get some healthy ones - put them under the middle of the areas that are sagging - start slowly jacking them up over a period of time until you get the floor back to level. Do it slowly so the building will have a chance to settle back into place. I doubt they had an I beam with a crown in it - way too complicated for a resie project - they just did not spec one large enough to carry the load. > If you can't recover anything from the builder - why not buy a couple > of those screw jacks - get some healthy ones - put them under the [quoted text clipped - 5 lines] > a resie project - they just did not spec one large enough to carry the > load. I don't know--OP says it was 8-1/4 ft deep x 5-1/4 ft wide--that ought to hold quite a bit I'd think... :) Sounds like the I-beam may have been dropped sometime during transport or installation, thereby 'it is bent'. If this is the case, it should have been installed with the crown up. Bryan "The Monk" Chaisone Are you telling us the 40 foot beam is taller than a room? If so, then where is the space for putting supports under the beam? Did you mean 40 foot long by 8.25 inches high by 5.25 inches wide? > Thank you for the many responses. I hope I answer everyones > questions...If you need pictures let me know. [quoted text clipped - 11 lines] > BTW: The Ohio Home Builders Association states the floor should be > level for 3/8"over 32" length. > Are you telling us the 40 foot beam is taller than a room? > If so, then where is the space for putting supports under the > beam? Did you mean 40 foot long by 8.25 inches high by 5.25 > inches wide? Pretty obvious I would think... :) Seems like a case of either inadequate support under the support columns or simply not leveled initially...as I read it, if one support were low he would have an unsupported span of roughly 26-28' which if there's a concentrated load (say a double-wide 'fridge, for example) right there could lead to a nice sag... Steel beam in a house that is only 8.5 inches high ... is rather small already. The architect would never permit support spacing more than about every 8 feet. With 12 inch beams, we install support about every 8 feet. Beam upside down ... my a.s. If the beam is only 8.5 inches high and supports are every 15 feet, then the builder has no right to be a builder. Start looking for other serious human safety issues. This guy is trying to kill people. > Pretty obvious I would think... :) > [quoted text clipped - 3 lines] > concentrated load (say a double-wide 'fridge, for example) right there > could lead to a nice sag... OP- The info you supplied is very useful in allowing the ng to comment on the install. With a fair amount of certainty: The beam is not upside The short post is letting the beam sag at the point & thereby effecting the performance of the beam elsewhere w/o plans (ie an idea of the loading) it's hard to say if the beam is too light a section but I ran a quick calc of a uniformly loaded continuous beam configuraton uisng a W8x21 At first, I would guessed that the beam was too light but a rough look says it's ok. I'd make sure the intermediate supports were at the same height as the end supports. At that point everything should be fine. Who spec'd the beam originally ? Builder or ? If other than the builder check w/ them. If after truing up the supports there is still excessive sag (btw some sag is allowed, it's got to deflect to take load) Is there an unusual floor plan above the beam such that a concetrated load is being taken into the center of hte center span? My calcs say that for a unifromly loaded situtation the center span should have very little deflection; about 10% of the max side span dlefection. Politely tell the builder to true up all the supports & knock off the BS about upside down steel wide flanges just out of curiosity what size footings do the intermediate supports have? cheers Bob Hi Guys Am I missing something here. Firstly, as many have said, assuming this is a standard off the shelf I beam, then you can install any way up ( but not sideways ) i.e. the web is vertical Secondly if you are getting 3/8" deflection in 13' span this is just about right for max deflection ( 1/360) not sure if your regs are the same in your part of the world However, I hope the beam is fully loaded when deflecting this much Next, putting in stronger posts will do nothing to strengthen the beam, unless you use wide cap plates and gusset stiffeners, which may or may not be aesthetically possible The clear and obvious way to proceed with this, is to ask your structural Engineer to check the calcs, or perhaps it may be prudent to use an independent one Hope this helps David |
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