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Discussion Starter #1
I have a ceiling that is run with 2x6's. The room is 22'x13' and the joist span the 22'. At the moment there is roughly a 1.5" to 2" sag in the middle. The joist run 16" OC.
The attic space is used for storage.
My question is should I run a steel I-beam across the center and jack it up.
Or can I jack up the ceiling and run 2x4's down from the roof and attach the 2x4's to the joist.
I am open to any other options those just came to mind first.
Thanks,
 

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Youre best off putting in a beam or built up girder. They never should have been spanned over that distance. You can look up. Joist span table online. If you have any other questions or need any advice let me know
 

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You might need an engineer.

Besides anybuilding code rules, insurance rules, and the issues of load and span, also think about how that load reaches the earth below. "Load path"

It should only cost a few hundred bucks to have a structural engineer spec the job.


What do I mean by load path? Your house sounds like mine, except that my joists in the problem room used to be supported in the middle by a load bearing wall. Someone removed the wall many years ago, and now the plaster ceiling and joists are slowly collapsing into the master bedroom (which we don't use for obvious reason).

If we only wanted to support the ceiling and insulation above we might try designing the repair on our own. One end of a beam would tie in above the foundation, but the other end of that beam would send a load down to the floor of that room, and under that spot is.... another room but no support. The spot is about five feet from the end of a double joist. On one hand, that should be fine, since there used to be a wall there loading it in much the same way. But that was back when the attic was used for bat roosting and little else.

We're going to make use of the attic space, and that means we'll be loading it in a way that was not considered when it was built. So..... we're avoiding the anxiety and making sure there are no problems about resale, insurance, or code, by working with the engineer.
 

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Discussion Starter #4
Thanks for the reply's. I know they shouldn't have built it this way. If they would have spanned them the 13' I might of been alright.
I had an engineer (my brother-n-law) come in and he recommended putting in a steel I-beam in the middle. That way I can save in head space in the room.
 

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You are fortunate to have a brother in law engineer willing to do design work for you. Personally I never perform design work for relatives, far too many potential issues related to code interpretation, lawsuits, disappointment, overseeing the work etc.
 

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To really not lose any headroom at all, you might be able to cut the joists at midspan, and hang them on a beam hidden above the ceiling, which is what we're going to do (after repairs/reinforcing to the load path).
 

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I have a ceiling that is run with 2x6's. The room is 22'x13' and the joist span the 22'. At the moment there is roughly a 1.5" to 2" sag in the middle. The joist run 16" OC.
The attic space is used for storage.
My question is should I run a steel I-beam across the center and jack it up.
Or can I jack up the ceiling and run 2x4's down from the roof and attach the 2x4's to the joist.
I am open to any other options those just came to mind first.
Thanks,
Are the ceiling joists and rafters running the same direction?

Thanks for the reply's. I know they shouldn't have built it this way. If they would have spanned them the 13' I might of been alright.
I had an engineer (my brother-n-law) come in and he recommended putting in a steel I-beam in the middle. That way I can save in head space in the room.
Sorry to tell you, but your B-I-L has no idea what he's talking about. All you have to do is put a flush double 2x8 or double 2x10, 13' header in at mid-span to carry the 11' 2x6's and cut the 2x6's and add joists hangers. Post underneath the header at each end.

There is no way in the world that you need a piece of steel for a 13' span carrying 11' 2x6 ceiling joists.
 

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We thought of that too, back when we were thinking of just passing the new support UNDER the existing joists. And we thought steel since it woudl take up less headroom than a 2x10 header. But then we found an article in FHB about hiding the header above the finished surface of the ceiling. perfect solution.

(If you look at the article, the author neglected to include temporary rafter ties when they cut the joists on that job)
 

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I'm guessing if they cut that big a corner on the ceiling joists, the rafters aren't overbuilt either.

I'm a bit surprized you haven't had more than just the sag issue if you were using the attic as storage too.
 

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Discussion Starter #10
I think I will flush cut the 2x6's and add a double 2x10. I really didn't want to add a beam down the middle of the room.
Would I then need to add rafter ties to add strength?

The joist and rafters run in the same direction and they both all 2x6's.

I bought the house and completely gutted it and have slowly been running into problems. This attic space wasn't storage before, but I wanted to turn it into a storage space. Should I reconsider, or will I be alright with a support beam being added.

Thanks,
 

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I think I will flush cut the 2x6's and add a double 2x10. I really didn't want to add a beam down the middle of the room.
Would I then need to add rafter ties to add strength?

The joist and rafters run in the same direction and they both all 2x6's.

I bought the house and completely gutted it and have slowly been running into problems. This attic space wasn't storage before, but I wanted to turn it into a storage space. Should I reconsider, or will I be alright with a support beam being added.

Thanks,
You have been told that you can do it. It does work. Are you getting permits and inspections? Before you cut anything, are you planning on bracing the rafter walls?
 

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Now more than ever I think you should hire (ie pay) a structural engineer to look over the whole project.


BTW, I did not say you can do this. Your 2x6 joists would end up spanning 11 feet for attic storage. I have no idea if code allows that long a span. Maybe you need TWO beams to conform to code, or additional joist material of some sort. Then there's the question of how your roof is framed... does it send any of its load to these joists? All I said was if you need a beam to comply with code and good engineering, there may be a way to hide it in the attic instead of in the headroom, and your professional can tell you the specs for that option. But I did not say this is a good option for you because I don't know.
 

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Discussion Starter #13
You have been told that you can do it. It does work. Are you getting permits and inspections? Before you cut anything, are you planning on bracing the rafter walls?
I haven't pulled any permits for the project. After ripping into the house I am afraid they would make me bull doze it over. There has been so many screws up thing I don't think you would believe me. Yes I planned on bracing and supporting everything first.

Also I will be sure to check with an engineer to see if I can hide the beam up in the rafters.
 

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I had a simular issue, had an 18' span with old growth 2x6 redwood, it never sagged but I've been replacing them with new doug fir #2 2x6 and noticed movement when I walked on them. I plan on reusing the old 2x6's in between the new ones or making them 4x6's
Would a 4x6 cover the span for you and not sag?
 

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When my structural engineer eyeballed my job a couple weeks ago I asked this very question. He said adding more 2x6 material would increase the limit of weight the floor can support, but would not eliminate bounce. For that, he said I'd need to use wider (ie taller) sisters.
 

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I don't know if I agree with your engineer. My 72 year old ceiling does not bounce or sag at all. They are 6" tall, the width is greater than the 2x6's I bought new. I think the "finished size" of the 2x6 is 1.5 x 5.5 based on finished sizes my old 2x6's are more like a 3x6. Just doing a quick check, it's at least 1/2" thicker. Also this is fine grain redwood. I compared it to a new one and the spacing of the growth lines was vastly different.
I bet if I took 2 modern 2x6' and glued & screwed them together with some plywood in the middle it would knock out most of that bounce.
I think this also says something about all this new fast growth undersized wood that we're being sold.
 

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could be Jay. On the other hand, what matters is if the city inspector agrees and in any case, we opted to go with 2x12s and blow the entire depth with cellulose. Thanks for the idea though.

BTW, I should have said in my original post that we were talking about going from just having an attic ceiling (the original 2x6s) to getting specs for an attic office floor (heavy on the paper storage). We're putting in the joists for the office now and insulating with cellulose, expecting that if we're still in a couple years we'll come back and remove the insulation and finish the space. So the 2x12s provide function either way.
 
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