What Is a LVL Span Chart? Your Guide to Safe Beam Sizing

You’re staring at a floor plan, wondering if that 12-foot opening in the kitchen needs a steel I-beam or if you can get away with a built-up LVL. Guessing isn't an option. If you undersize your beam, you’ll deal with bouncy floors or, worse, structural sagging that costs thousands to fix. This lvl span chart provides the baseline engineering data to get your beam sizing right the first time. For instance, notice the jump in capacity when moving from a 9.5-inch 1-ply beam—which tops out at a 10-foot floor span—to a 9.5-inch 3-ply configuration, which can safely span up to 20 feet. Choosing the wrong ply count here doesn't just mean a "bouncy" floor; it can lead to catastrophic deflection that exceeds the industry-standard L/360 limit, potentially failing your final framing inspection.

Reading the Chart: Getting Your Numbers Right

Before you pick a number off the table, you have to understand what you’re actually supporting. A beam carries both dead loads—the weight of your joists and flooring—and live loads, such as furniture and occupants. As a case in point, our data assumes a 40 psf live load for floor spans. If you're designing for a high-load area, you can't simply use the roof span column (which is calculated at a lower 30 psf live load) for a floor application; doing so would result in a dangerously undersized beam that lacks the necessary stiffness to prevent vibration and structural failure.

The span length is the distance between your bearing points, and the relationship between depth and ply count is critical. As you move up to a 14-inch deep member, a 3-ply configuration allows for a massive 28-foot floor span, whereas a 1-ply version of the same depth is limited to just 14 feet. This is why you must verify your specific tributary width; if your beam is carrying a wider section of the house than the 10-12 feet assumed in our chart, the provided spans may be too aggressive for your specific load path.

Why Thickness and Depth Matter

Beam thickness—or the number of plies—is just as important as depth because it dictates the load-carrying capacity of the assembly. A 16-inch, 3-ply LVL provides the highest structural support in our table, capable of spanning 30 feet for floors and 37 feet for roofs. This is the difference between an open-concept living space and a room requiring unsightly, mid-span support columns. However, always remember that these figures are for reference only. Local building codes, snow loads, and specific manufacturer specs are the final word. If your city inspector sees a 16-inch, 3-ply beam specified for a 30-foot span, they'll expect to see the engineering calc to back it up, as these numbers are your starting point, not your final permit.

Navigating Load Paths and Span Calculations

When you look at the chart, start by identifying your load type. The 9.5-inch 1-ply beam handles a 10-foot floor span, but that same beam jumps to a 12-foot roof span. This happens because roof loads are generally lighter than floor loads. If you try to push that 1-ply beam to 12 feet for a floor, you’ll end up with a floor that feels like a trampoline. Always check the structural load requirements for your specific project before picking a row.

Decoding the Ply and Depth Relationship

The number of plies dictates how much weight you can stack on the beam. Look at the 11.875-inch depth category. A 1-ply version hits its limit at 12 feet for floors. Bump that to 3-ply, and you effectively double your capacity to 24 feet. That’s a massive difference for an open floor plan—it’s the difference between needing a support post in the middle of your kitchen island or having a clean, clear span. If you're stuck between two sizes, always go bigger. Never shave off an inch of depth to save a few bucks on lumber.

Field Observations on Common Failures

In the field, I often see contractors try to "cheat" the span by doubling up a beam that’s too shallow. They think two 9.5-inch beams equal an 18-inch beam. They don't. A 14-inch 2-ply beam allows for a 22-foot floor span, but if you drop to a 9.5-inch 3-ply beam, you lose 2 feet of span even with more wood. Depth is the primary driver of stiffness. Don't sacrifice it for convenience. You can download this chart as a PDF to keep on your job site for quick reference during framing.

Handling the In-Between Scenarios

What if your span is 13 feet and the chart only shows 12-foot and 14-foot options? You must default to the higher requirement. Designing for the 14-foot span is the only safe way to ensure your beam doesn't sag over time. If your calculated span lands exactly between rows, the industry standard demands that you use the next larger beam size. Always verify your tributary area—the actual square footage of floor or roof weight the beam carries—because if that area exceeds 12 feet, even these maximums might be too optimistic. When in doubt, call an engineer. A few hundred dollars for a stamp is cheaper than tearing out a finished ceiling to sister a sagging beam.

Practical Tips for Installing LVL Beams

Proper installation keeps your beam from twisting or failing under pressure. Always ensure your bearing points at each end are solid—typically at least 3.5 inches of full-depth contact on a stud pack or concrete wall. Anything less risks crushing the wood fibers over time. Never cut, notch, or drill holes in the top or bottom flanges of an LVL; doing so destroys the structural integrity of the veneers and invites immediate deflection. If it's requisite to run plumbing or electrical, keep your holes in the center third of the beam depth and avoid the ends entirely.

• Use temporary shoring: Always prop up the floor joists with adjustable steel posts before removing the old wall. Don't rely on your back to hold the load.
• Keep it dry: LVLs are engineered for interior use. If they get soaked during framing, they can swell or delaminate. Cover your work.
• Check your hardware: Use the exact hangers specified by the manufacturer. Using a standard nail-in bracket for a heavy 3-ply beam is a recipe for disaster.

Frequently Asked Questions About Beam Spans

Can I use a standard lumber span table for LVL? Never. LVL is significantly stronger and stiffer than solid-sawn timber. Using a standard table will result in massive over-building and wasted money.

What if my span exceeds the chart? If your required span is longer than the values listed, you need a custom calculation. Don't guess. Contact a licensed structural engineer.

How do I handle point loads from posts above? Point loads concentrate massive weight on one spot. Our standard chart assumes a uniform load. If you have a post landing on your beam, you need a custom design to prevent localized crushing.

You can download the PDF version of this lvl span chart to keep in your truck. Print this out and save the guide for your next framing job. Having the right numbers on-site is the best way to keep your inspector happy and your floor joists level.