Don_P frequently cites the code citation, I don't know it off the top of my head. Code requires all splices to be supported by a stud or post. You would be trying to support those 20-2x12s with only 4-2x12s spanning a greater distance than the 20 (13'-6" vs 11'). You can think about it logically that you the beam will be supporting 20-2x12s (10, 16"o/c, 2 sides) in that 13'-6". Since you have a 13'-6" between your posts you will need to cut down the span (more posts) or use an LVL. For widths between those shown, spans are permitted to be interpolated.Ĥ-2x12's can span 9'-1" in a 36 foot wide building and 10'-2" in a 28 foot building, so to interpolate (split the difference), 4-2x12s should be able to span 9'-7" according to code. Building width is measured perpendicular to the ridge. Your building is 32 ft wide, which is right in between the 28 and 36 foot columns of the chart. It sounds like the girders under the joists will be an "interior bearing wall" span supporting "one floor only." They have charts for girders and headers in the ICC. Hopefully Don_P will be along sometime soon and see if I have messed up or not. Perhaps you need some engineered wood, or steel. That still FAILS the fiberstress in bending test. Using three columns across the length reduces the span for each to approximately 120" (10 ft) The calculator tells me that 4 layers of 2x12 (actual beam width of 6" and depth of 11.25" will FAIL the Fiberstress in bending test and the deflection test. (the calc is fixed to use a value of L/360 on floors)īut let's see what happens when we use. Using Don_P's simple beam calculator and the following data for SYP. Half of that will rest on the center beam and a quarter on each side wall.Ģ4750 / 2 = 12375 on the center beam for each segment. If we call the LL to be 40 PSF, let's call the DL out at 15 PSF. Let's call that a 32 x 42 building that = 1344 sq ft.ĭivide that into three parts = 448 sq ft per section I always though it was better to stagger the joints to minimize a hinge effect over the column, but he says his way is correct. My contractor (NOT an engineer) says a beam built up out of 3 or 4 2X12's will be 'plenty', but of course, the inspector has to believe that, too.Īs an aside, my contractor builds such beams with all of the joints over the column. Materials available locally are #2 southern yellow pine- strong stuff. Design load should be 40 psf minimum live load, and I want a L/480 stiffness. I don't have enough room to put them on top of the carrier beam, so they will be attached with hangers. They will be hung from ledgers at the edges, and the carrier beam in the middle. Specs- The floor joists will be 2X12's on 16" centers. The lumber yard said I would need an LVL, but what did they do before those were around? I show two evenly spaced support posts, but could go with three if it would help. I'm attaching a drawing with the dimensions. Let's assume you have an LVL beam with a width of 5 inches, a depth of 12 inches, and it needs to support a uniform load of 1,000 pounds per square foot.I'm wondering if there's a way to prescriptively calculate the carrier beam I need for my main floor. Review Maximum Safe Span: The calculated maximum safe span for the LVL beam will be displayed on the page.Calculate: Click the "Calculate" button, and the calculator will compute the maximum safe span based on the input values.Input Data: Enter these values into the calculator fields.Gather Information: You'll need information such as the LVL beam width, depth, and the uniform load that the beam will support.Maximum Safe Span: feet How to Use the LVL Span Calculator: Enter the required information below to calculate the maximum safe span for LVL beams or joists: LVL Beam Width (inches):
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