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Rick Hubbard
03-26-2008, 1:37 PM
When I first started putting my shop together about 6 years ago, I could not imagine that I would ever fill it up. Now I am looking for ways to gain more “room to roam”. One thing I have decided to do (until I can afford to build an addition) is to do away with the “island” you see in the center of this picture. What is inside this “island” is a 4X4 post that provides support for the ceiling. It (the post) is about 6 feet from the supporting wall and another similar post. The post supports a “made” made from 3 2 X 10’s nailed together. I don’t want to just remove the 4X4 because of the HUGE snow loads here. My idea is to build ANOTHER “beam” using 3 2 X 8’s supported on each end by doubled up 2 X 8’s.
The question I have is whether this will be sufficient to bear the weight of the roof across this 12 foot span.
The picture might provide a better idea of what I'm trying to do.
Thanks for the help.
Rick

Brian Effinger
03-26-2008, 1:44 PM
That's a difficult question to answer, because from this small snapshot, and not knowing exactly what spans and load are on this beam. I suspect, however, that the triple 2x10 would not work if you removed the post. One suggestion I could make is adding a steel plate to each side of the 2x10 and bolting together every 24". These steel plates would have to span from the bearing wall to the other post. This is only a suggestion though, and I strongly suggest contacting an architect of a structural engineer to take a look at your situation and make a recommendation. Your local building inspector should know of a few good ones that he would recommend.

Ben Cadotte
03-26-2008, 1:51 PM
Don't know how your roof is made or your snow loads. And your post is a little confusing. Sounds like you have 3-2x10's now and want to replace them with 3-2x8's at a longer length. Or maybe you want to just add them to the outside of the current beam?

I would guess that 3-2x10's spanning 12' would support quite a bit of roof load. Is the current "beam" you have now in 2 pieces (joint above the middle support post)? If you are really worried about it not being strong enough. Eassiest thing to do it get a 16' garage door header and cut to length and install it (with the post removed of course) assuming you can take out the original and the original is not 1 piece length wise.

To really tell you a definate answer, need some more information on the roof design.

Anthony Whitesell
03-26-2008, 1:54 PM
Sorry Rick, but I'm not following where the triple 2x8 would be placed in relation to the triple 2x10 center joist.

If the triple 2x8 is going to be placed under the triple 2x10, I would also look at the possibility of a small steel i-beam instead of the triple 2x8 held up at either end to maintain your head room. (At 6+ feet tall, I think of those things)

Most lolly-columns require their out footing and they're not allow to rest only on the concrete slab. Not sure if it applies to this situation, but I thought I would throw that out there as well.

David DeCristoforo
03-26-2008, 1:59 PM
You need to talk to a structural engineer. He/she can calculate the snow load and span and evaluate the footing conditions and tell you what you need. A steel beam might be the better option...

YM

Jim Becker
03-26-2008, 2:01 PM
What YM said...get a professional evaluation even if if costs you a few bucks. Not something to fool around with...

Ben Cadotte
03-26-2008, 2:02 PM
Is the area where the beam is an old original outside wall? And either the area in the forground or background an addition? Having posts 6' apart in the middle of a room is kind of unusual. So I am thinking its an original bearing wall.

Rick Hubbard
03-26-2008, 2:04 PM
Sorry Rick, but I'm not following where the triple 2x8 would be placed in relation to the triple 2x10 center joist.



My notion is to run the triple 2 X 8 UNDER the existing 2 X 10. Not sure if this clarifies or not

Rick Hubbard
03-26-2008, 2:50 PM
Is the area where the beam is an old original outside wall? And either the area in the forground or background an addition? Having posts 6' apart in the middle of a room is kind of unusual. So I am thinking its an original bearing wall.

Actually, no it was not a bearing wall- I think it may have orginally been a clear-span between the outside walls and someone placed the 4 x 4's there afterward.

In fact, as it turns out, I may have answered my own question. I looked at the 16' span that goes between my kitchen and dining room at the "living end" of the house and I see that is the same kind of set-up: triple 2X10's holding up the roof trusses. There is no sign of a problem there, so I suspect there would be no problem with the 12' span in the shop, especially if I went forward with my initial plan to reinforce the whole thing with triple 2 X 8's.

It is really nice to live in a place where people think CODE is the little numbers on their Hostess Twinkies that tells when they are no longer safe to eat.:rolleyes:

Ben Cadotte
03-26-2008, 3:55 PM
It is really nice to live in a place where people think CODE is the little numbers on their Hostess Twinkies that tells when they are no longer safe to eat.:rolleyes:

I was almost in shock when I went to the local inspector for my town and found out how much can be done with no permit required. Last town you needed a permit to sneeze.

Maine is a different way of life, and I am enjoying it so far. Just a hop skip and a jump from you.

Lee Schierer
03-26-2008, 4:50 PM
A year or so ago I had the "made" beam in my shop replaced. I had noted a significant sag in it due to the poor construction and a crack that devloped. I replaced a triple 2 x 10 made beam with two 2 x 12 engineered wood beams. My total span is about 18.5 feet. After reviewing the design with a beam supplier and getting the loads figured out with them, I blocked up the existing ceiling joists with a temporary wall to take the load, then removed the old beam, slipped in the new beams with the help of some friends, bolted the two new beams ot each other, lremoved the temp wall and checked the sag of the new beam. It sagged less than 1/4" when the weight was put on it.

Talk with the suppliers for engineered beams and they will help you size the correct beam for your shop to have a free span. Putting a beam under a beam doesn't look good and probably won't give a good result. Get professional help on sizing the proper support so you don't have structural issues.

Brian Effinger
03-26-2008, 5:19 PM
Rick,
If you have dimensioned construction drawings of the house that you could copy and fax or email me, I could run a quick calculation and see it the triple 2x10 would hold. Even if you hand drew a sketch of the room, and a drawing of what is above it, that would be enough.

Brian

Richard Daly
03-26-2008, 9:10 PM
I agree with Ben You should have a Fitch plate in there ..The very least would be a good quality 3/4 Plywood between your beams. This would help greatly..They put Plywood as a Fitch plate between 2/12 on the 16 ft span on garage doors.
Keep your fingers out of joiners PLEASE....Stubby

Peter Quinn
03-26-2008, 10:39 PM
What your talking about doing sounds more like a leaf spring system on an old pickup than a carrying beam. For saftey I see steel or a glue lam ( or possibly a monolithic timber) in your future. Worst case keep some jack stands handy in case your remedy starts to sag a bit.

Bob Feeser
03-26-2008, 11:26 PM
One thing that is being left out of the equation; is it a flat roof?

Rick Hubbard
03-27-2008, 8:27 AM
Thanks everyone, for offering advice and admonition about this.

After looking at what everyone has had to say, two things stand out:

First, I should seek professional help (hmmm, that looks like an odd phrase now that I have typed it out).
Second, I most likely should be thinking about STEEL.

Either of these options, by themselves, smell of money. Both of them combined smell like SERIOUS money. I’m tempted just to abort the whole idea. My wife says if I need more room, maybe I should get rid of some tools:eek: (I don’t like the sound of that option much either, to be perfectly frank).

Cliff Rohrabacher
03-27-2008, 9:06 AM
A 19 KiPs steel 8" wide-flange will take that span and any snow and rain load you can throw at it.

I have a 40 * 20 flat roof over my garage. On top of that is a spruce recreational deck. The 40' run is supported by a 19 KiPs wide-flange. I have one (count 'em) one pillar in the center which I remove occaisionally. The beam is supporting 20 feet between each wall and the pillar.

The other direction (the 20 foot run) is supported by 2*10s blocked at 16" OC. They are fixed in the lower shelf of the wide flange on top of a 2*4 that is fixed to the flange & runs the length of the flange and is nailed to the joists.

I have had snow loads of 2 and a half feet that got rained on for days at a time - just sitting there. Nothing moves nothing squeaks.

Anthony Whitesell
03-27-2008, 9:26 AM
That clarifies it well enough. Simply reinforcing it from underneath with out first removing the weight off the old beam will not be as effective as you might think. Currently the old beam has weight on it and is stressed (in a good way), if you just add a beam below it it will not bear any weight immediately. The triple 2x10 will have to have bear enough weight (most likely due to the snow load and some due to age) to get the triple 2x8 under stress before it will start absorbing the load. If you first relieve the weight from the triple 2x10, then install the triple 2x8 (i-beam, steel plates) when the load is reapplied and it will be immediately redistirbuted. All the reinforcement installed will immediately start to carry its share of the load and the benefits you expect will be there.

David DeCristoforo
03-27-2008, 11:23 AM
"Simply reinforcing it from underneath with out first removing the weight off the old beam will not be as effective as you might think".

There is another question here also. The existing beam is (presumably) supported at the ends by some direct load bearing, either a pier and post or by direct transfer to the stem wall/footing. The additional beam will not be. If the beam is terminated at the wall, it might be supported only by the floor. If the beam is "let in" to the wall so that the ends are "picked up" by whatever is supporting the existing beam, that means getting into the wall. It could get complicated.

"Either of these options, by themselves, smell of money. Both of them combined smell like SERIOUS money."

I would think that the cost of a steel beam will not be as much as you think. And you may be fine with the triple 2 bys. But you are not going to know for sure until you have the math done. A few years ago, I had an engineer evaluate a similar structural question and the charge was $1,200. That's not cheap but you are talking about modifying the underpinnings of your house. Personally, I would not do this without the confidence a structural evaluation would provide. Especially in an area with heavy snow loads.

YM