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I'm looking for your opinions on this load bearing wall and how it pertains to my roof structure. Here are some pictures

End of beam on load-bearing wall: End of beam

Wider view of load-bearing: Wider view of beam

Attic above wall: Attic above wall

We are looking to open up about a 16' wall which I was lead to believe is load bearing with the double header. So I had the local lumber yard do up the calculations for LVL's and they came back with (3) 1 3/4" x 14" x 20'. After talking with a few people and looking at my roof structure, it seems like this may be overkill for what we have. The wall that we are looking to remove is on the first main floor with only the unfinished attic above it. The basement has columns roughly every 10' or so down the middle. I should also state there are joists sitting on the wall in the attic, it's just buried in the insulation.

Anyone have any experience with this type of scenario?

Thanks in advance!

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    I would dig down and see if there is a splice under the insulation above the wall you want to remove. The wall looks to be 9-10 feet from the exterior wall. Your rafters are sitting on the exterior walls from what I can see. If there is no splice then the question would be are they 2x6 or 2x4 depending on the span if there is no splice it looks to only be supporting the sheetrock and insulation. The columns in the basement are to support the floor of the ground level living space. – Ed Beal Mar 21 '16 at 22:55
  • You're going to have to include a blueprint, and/or some better photos of what's above the wall. Without more detail, it's impossible to say for sure what's required. – Tester101 Mar 21 '16 at 23:52
  • The absence of a splice does not imply that the wall below isn't load bearing. Midspan moment in a simply supported beam under uniform loading is wL^2/8. If you double L, then you quadruple the midspan moment, thereby quadrupling the bending stress. – popham Apr 19 at 5:38
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I see there were a few responses to this and I never responded 4 years ago. We ended up using 3 LVL's glued/screwed together and hoisted those into place. We haven't had any problems and we get multiple feet of snow each year. Here's a pic from 4 years ago when we set the beams.enter image description here

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  • Welcome back, and thanks for posting your answer. Are those vertical lines joints? How did you keep them strong? – Daniel Griscom Apr 20 at 12:19
  • To be honest I don't know. My uncle was the one that put it all together. I just helped hoist those beasts into place! – Alex Apr 20 at 13:04
  • LVLs are constructed from multiple layers of wood. Those vertical lines are joints, but they're joints in only a single layer. By staggering such joints around, LVLs can be cheaply be constructed to any length (unfortunately they can't be cheaply shipped for any length--48' max by truck and 80' max by train). – popham May 11 at 17:53
  • It is seldom that we get to see a follow-up on projects. Thanks! It looks like your Uncle did a good job. – Charles Jun 25 at 16:43
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You can size the beam with a basic load calculator (that's what the lumber yard did). One example is bc-calc (www.bccalc.com). Don't just assume that any applicable load has to come from the roof.

The ceiling joist weren't designed to handle the ceiling's weight (service personnel, joist, flooring, wall board, insulation, HVAC, electrical, fasteners, paint, etc.) from exterior-wall to exterior-wall. A person new to beam specification would be well-advised to just use the weight of the entire ceiling. Bad beam specifications usually come from inaccurate load input.

The studs under each end of a beam spanning 16ft should be sitting on something solid down to the footing level (look in your crawl space). A 16 foot span is significant. Ceiling sag can be a building-wide structural issue. Don't under-build, you'll regret it. You won't regret over-building.

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Homes are built with the outside walls first supporting the roof rafters or trusses. Interior walls are added later.

Usually the only interior walls that might be load bearing are where an addition was put on to a house on a wall under a downslope part of the roof.

Look at your roof, the walls under any downslope parts of the roof are load bearing. Gable ends are not load bearing. Walls that run parallel to the trusses are not load bearing.

The "beam" you have a picture of isn't sized properly to be a beam. It would have to be a minimum of two - 2x8's nailed together. So it appears it was just used for structure to attach the drywall to.

Good luck!

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  • Agreed on the "beam". From the small gap at the top plate, it doesn't even look like it's loaded. – Comintern Mar 22 '16 at 2:43
  • It's very common for an interior wall to run below the roof's ridge to halve the span length of floor joists. It's very common for an interior wall to support the ceiling below the roof's ridge to provide for the live load demands of the attic space. – popham Apr 19 at 5:48
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What load? I agree with Ed Beal. Unless your ceiling joists are tiny or splitting the span & meeting on top of this wall, I don't see any load nor need for any beams of any sort. Rake back that attic insulation to further confirm no load or what support may be needed.

Meaning, if your ceiling joists are singular full span 2x8 or taller sticks & just running over the wall, then you don't need to do anything before, during nor after removal of the wall. A Double Top-Plate is no indication of anything & many times is just a filler.

Additionally, those many huge LVL's is way overkill, except for putting a Hot Tub or a Bank Safe in the attic. You'd cut the joists, put just 1 of those LVL's (or a 2x12) in that cut & hang the joists from the LVL within the attic.

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  • I tend to use a single asterisk for less intrusive, less shouty emphasis - just my $0.02 worth. P.S. LVL=Laminated Veneer Lumber header/beam right? (I had to look it up). – RedGrittyBrick Mar 22 '16 at 9:33
  • Yep. The LVL's are much stronger than dimensional lumber. I just can't imagine what his lumber yard was thinking. That package would be for a basement beam in a 4-story house with old-timey actual plaster & full mud bed walls & floors bathrooms. – Iggy Mar 22 '16 at 13:01
  • That looks like uninhabited attic with storage (see Table 1607.1 from the IBC). The live load, then, is 20psf and the dead load is about 3psf. Deflection will probably decide the design of that beam. Table 1604.3 from the IBC indicates that the beam must keep that 20psf live load's deflection below L/360. – popham Apr 19 at 6:07
  • You are correct, but that's all handled and very much exceeded by the ceiling joists. Even if he had just 2x8's there would be no structural ceiling concern nor threat of any kind from that attic. The wall runs inline or parallel with the ceiling joists and even rafters. – Iggy Apr 19 at 12:26
  • @Iggy, according to the OP: "there are joists sitting on the wall in the attic." If the OP had said that "there is a joist sitting on the wall in the attic," then you would have a point. And I'm 95% sure that the wall was load bearing. Nobody's going to waste the money on ceiling supports to carry all of the load. If the designer wanted to support the ceiling without help from the wall, then he would have used roof trusses since truss web members can shorten ceiling span lengths. My 5% hedge conservatively accounts for incompetent design. – popham May 11 at 18:09

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