*
Have started remodeling the first floor of c.1825 federal-style brick home we just purchased. Found that on one of the main beams in the home (beam size is 8″x8″, span is 20′) that the first floor wall supporting it was not built on beam center but is off-center by approx. 6″ so that the wall is actually supporting the 2nd floor joists directly and not the beam. One end of the beam in question is supported by an exterior wall, the other end is mortised into another beam running perpendicular to this one and a 2×4 support wall underneath. Should this off-center wall be “corrected” as part of our remodel since everything is opened up? Is it anything to worry about? Also, the beam sags almost 3″ in middle of span. Would like to jack it up and get it (and 2nd flr) closer to level. Any do’s or dont’s would be welcomed.
Thanks in advance.
Discussion Forum
Discussion Forum
Up Next
Video Shorts
Featured Story
Listeners write in about continuing education, minisplit heat pumps, compact home shops, and building science.
Highlights
"I have learned so much thanks to the searchable articles on the FHB website. I can confidently say that I expect to be a life-long subscriber." - M.K.
Replies
*
some scale section drawings would help make this clearer than mud...
*If you are doing a remodel, you will need to replace the beam - it is not to code.I suggest that you hire a local engineer to look at the situation.
*Isn't the residential rule of thumb that a bearing wall supporting one floor can be offset from the beam below by the depth of the joists? So, for example, the wall on a 2x10-joisted floor could miss the beam by as much as 9 1/4 in.? I think that you could call the beam undersized, but you could also call it overspanned. Seems to me that slowly (I'm talking months) raising it with a couple of railroad jacks and eventually supporting it on two lally columns on new footings in the basement would handle the situation in most simple houses. Presumably, you're talking about a 2-story house that's say, between 20 and 30 ft. wide, and where the beam runs the center of the house's length. The 20 ft. span would become three 6 ft. 8 in. spans, which seems reasonable for an 8x8 that's been proven to handle a 20 ft. span, albeit with some sagging. Getting an engineer's view is probably sound advice, but the situation is really pretty simple. Andy
*Hiring an engineer sounds like the way to go. I did attach a drawing in MS Word format that gives a rough idea of the layout that I referred to in my first muddy mesage, just in case you wanted to look at it. Interestingly, the 1st fl joists in the basement have almost no sag. Most of it is in the beam I referred to on the 2nd fl. The support wall that is off-center beneath it is not the original wall, it was put there at a later point in time. The house is 30'wx40'l. Thanks.
*Andy, I wish no one had ever heard of that rule. They assume it will work for everything, including I-joists and floor trusses. But the rule of thumb doesn't take into account how much load is applied from above, the species of the wood, or the spacing of the joists.
*That's true - I tend to build simply - usually 2 story, 28 ft. wide, 16 in. OC, #2 or better D-fir joists. I've been told by building inspectors that that rule of thumb is fine. Andy
*The rule of thumb is base upon a 45 degree load path. Similar to brick above a lintel or soil bearing pressure.RD
*D....You want to hire an engineer and you have our permission...So why did you ask us about it?Andy has it down and others have explained the 45 degree load path thing. I'll add this...Many designs have indirect load paths. They are not the best designs and do fail or bend. In your home I would do what Andy said over time.I worked on a home that had 2' overhangs all around and after 30 years the sag was 1-2" in that 2'. I would never build that way with that high a sustained load...I do build decks that cantolever out...but the sustained loads are so much less than the design loads that it works well...along with slope not mattering anyway.near the stream,aj
*AJ, Guess I was looking for some direction from experienced folks like yourself on the best way to proceed before doing anything about the sagging problem. Truth is, hiring an engineer +/or contractor at this point in the project wasn't in the budget. I thought there might be a simple, low cost solution to the problem that I could handle myself, but maybe thats not in my, or the home's, best long term interests. This is my first big project, so I'll probably have lots of rookie questions. Thanks to all who responded.
*dc.. a picture is worth a thousand words... especially if you are asking a question about your house
*> The rule of thumb is base upon a 45 degree load path.I realize that, Rd. But rules of thumb don't work in every situation. Other things need to be taken into consideration, as I said before.
*DC...Leave the wall where it is. Add support under the beam as Andy outlined. If A guy like me went to your home to see the project, we could tell very quickly whether we would want engineers brought in...So find some locals help to look at your situation if you don't trust yourself.near the stream,aj