W16 Beam Sizes Chart: Weights & Dimensions
The AISC W16 series runs from W16x26 to W16x100: 11 shapes, all about 16 inches deep, weighing 26 to 100 lb per foot. They fall into three flange-width groups (about 5.5, 7 and 10.3 inches). W16x26 and W16x31 are among the most common floor beams in light commercial framing.
What are all the W16 beam sizes?
Dimensions below are from the AISC Shapes Database, consistent with the 16th Edition Steel Construction Manual. Depth is actual depth, not nominal. Click any designation for its full reference page.
| Section | Weight (lb/ft) | Depth d (in) | Flange width bf (in) | Web tw (in) | Flange tf (in) | Area (in²) | Ix (in⁴) | Sx (in³) |
|---|---|---|---|---|---|---|---|---|
| W16x26 | 26 | 15.69 | 5.50 | 0.250 | 0.345 | 7.68 | 301 | 38.4 |
| W16x31 | 31 | 15.88 | 5.525 | 0.275 | 0.440 | 9.12 | 375 | 47.2 |
| W16x36 | 36 | 15.86 | 6.985 | 0.295 | 0.430 | 10.6 | 448 | 56.5 |
| W16x40 | 40 | 16.01 | 6.995 | 0.305 | 0.505 | 11.8 | 518 | 64.7 |
| W16x45 | 45 | 16.13 | 7.035 | 0.345 | 0.565 | 13.3 | 586 | 72.7 |
| W16x50 | 50 | 16.26 | 7.07 | 0.380 | 0.630 | 14.7 | 659 | 81.0 |
| W16x57 | 57 | 16.43 | 7.12 | 0.430 | 0.715 | 16.8 | 758 | 92.2 |
| W16x67 | 67 | 16.33 | 10.235 | 0.395 | 0.665 | 19.7 | 954 | 117 |
| W16x77 | 77 | 16.52 | 10.295 | 0.455 | 0.760 | 22.6 | 1,110 | 134 |
| W16x89 | 89 | 16.75 | 10.365 | 0.525 | 0.875 | 26.2 | 1,300 | 155 |
| W16x100 | 100 | 16.97 | 10.425 | 0.585 | 0.985 | 29.4 | 1,490 | 175 |
Always confirm properties against the current AISC Shapes Database before using them for anything beyond estimating. Rolling tolerances on dimensions and weight are covered by ASTM A6, and most W16s today are ordered to ASTM A992. For more on grades, see our A992 vs A36 vs A500 guide.
A few things the table shows that are easy to miss:
- "W16" doesn't mean 16 inches. Depth runs from 15.69 to 16.97 inches. If you're checking clearance under a W16 or sizing a cap plate, use the actual d.
- The three flange groups behave like three different families. The 5.5-inch shapes (26 and 31) are efficient floor beams but floppy laterally. The 7-inch group (36 through 57) is the general-purpose middle. The 10-inch shapes (67 through 100) start to look like column-ish sections and show up as heavy girders, transfer beams and short heavily loaded spans.
- W16x67 is shallower than W16x57. It's a different flange family, so depth doesn't increase straight down the list.
If you need every W16 on a plan set counted rather than looked up, upload the drawings to SteelFlo. Each W16 callout on every sheet gets its own box you can check. The first 3 takeoffs are free.
Why are W16x26 and W16x31 the everyday floor beams?
On a typical office or retail floor with composite deck, infill beams spanning 25 to 35 feet at 8 to 10 foot spacing often land in the W14 to W18 range. W16x26 and W16x31 sit right in the middle of that, which is why you'll see them repeated dozens or hundreds of times on a floor plan.
| W16x26 | W16x31 | Difference | |
|---|---|---|---|
| Weight | 26 lb/ft | 31 lb/ft | +19% |
| Flange width | 5.50 in | 5.525 in | about the same |
| Flange thickness | 0.345 in | 0.440 in | +28% |
| Sx | 38.4 in³ | 47.2 in³ | +23% |
| Ix | 301 in⁴ | 375 in⁴ | +25% |
| 30-ft piece weight | 780 lb | 930 lb | +150 lb |
The W16x31 buys you about a quarter more stiffness and strength for 19% more steel, mostly through a thicker flange. On a floor with 200 infill beams averaging 30 feet, the jump from W16x26 to W16x31 adds 200 × 150 = 30,000 lb, or 15 tons. That's why it matters to count each one right. A plan with "W16x26 TYP" and a handful of W16x31 exceptions is exactly where a quick takeoff goes wrong.
Disclaimer: the engineer of record sizes members. These comparisons are for estimating and checking takeoffs, not for selecting beams.
How does W16 compare with W14 and W18 at similar weights?
Engineers pick depth for stiffness and floor-to-floor height. At similar weight, a deeper shape gives you more section modulus per pound. Here's how the common light shapes stack up:
| Section | Weight (lb/ft) | Depth d (in) | bf (in) | Sx (in³) | Sx per lb/ft |
|---|---|---|---|---|---|
| W12x26 | 26 | 12.22 | 6.49 | 33.4 | 1.28 |
| W14x26 | 26 | 13.91 | 5.025 | 35.3 | 1.36 |
| W16x26 | 26 | 15.69 | 5.50 | 38.4 | 1.48 |
| W14x30 | 30 | 13.84 | 6.73 | 42.0 | 1.40 |
| W16x31 | 31 | 15.88 | 5.525 | 47.2 | 1.52 |
| W18x35 | 35 | 17.70 | 6.00 | 57.6 | 1.65 |
| W16x40 | 40 | 16.01 | 6.995 | 64.7 | 1.62 |
| W18x40 | 40 | 17.90 | 6.015 | 68.4 | 1.71 |
What this means at bid time:
- When a plan swaps W16s for W14s (say, to save ceiling depth), expect more tonnage for the same loads. A W14x30 is still weaker in bending than a W16x31.
- When it swaps W16s for W18s, tonnage can drop, but the deeper beams may change connection sizes and coordination with MEP.
- Wide flange series overlap a lot, which is why our complete wide flange guide and the W12 chart and W14 chart are worth having open together.
How much does a W16 weigh at 30, 40 and 50 feet?
Piece weight is just weight per foot times length. These are handy for rigging, truck loading and checking that a crane pick isn't a surprise:
| Section | 30 ft (lb) | 40 ft (lb) | 50 ft (lb) |
|---|---|---|---|
| W16x26 | 780 | 1,040 | 1,300 |
| W16x31 | 930 | 1,240 | 1,550 |
| W16x36 | 1,080 | 1,440 | 1,800 |
| W16x40 | 1,200 | 1,600 | 2,000 |
| W16x45 | 1,350 | 1,800 | 2,250 |
| W16x50 | 1,500 | 2,000 | 2,500 |
| W16x57 | 1,710 | 2,280 | 2,850 |
| W16x67 | 2,010 | 2,680 | 3,350 |
| W16x77 | 2,310 | 3,080 | 3,850 |
| W16x89 | 2,670 | 3,560 | 4,450 |
| W16x100 | 3,000 | 4,000 | 5,000 |
These are bare-member weights. Add connection material (clip angles, shear tabs, stiffeners) for shipped weight. On simple framing that's commonly a few percent of the member weight, more on braced or moment frames. The beam weight calculation guide walks through the full math, or use the free steel weight calculator.
How should you price W16s by the foot?
Most estimators price W16s as material by the pound, then add fabrication and erection. A simple build-up for a single piece:
- Ordered length, not net length. W16s come in stock lengths, commonly 40 and 60 feet, with 50s available in some markets. A 28-foot beam either nests with another cut or leaves a drop. See stock lengths, nesting and drops for how that plays out.
- Weight. Ordered feet × lb/ft.
- Material cost. Weight × your current $/lb from your mill or service center. Material prices move monthly, so use a current quote, not last quarter's number.
- Fabrication. Cuts, copes, holes and connection material per piece. Copes and holes don't care much about weight, so a light W16x26 costs more to fabricate per pound than a W16x57.
Worked example, using an illustrative material price of $0.55/lb (check your current price before bidding):
- 24 pieces of W16x26 at 29'-6" net
- Nesting two per 60-foot stick (2 × 29.5 = 59 ft plus kerf) needs 12 sticks
- Ordered weight: 12 × 60 × 26 = 18,720 lb
- Material: 18,720 × $0.55 = $10,296
- Net weight in the building: 24 × 29.5 × 26 = 18,408 lb, so the drops are 312 lb (about 1.7%)
Ordering 40-foot sticks instead would mean one beam per stick with a 10'-6" drop each, 24 sticks and 24,960 lb ordered. That's 6,240 lb more steel unless you can use the drops elsewhere on the job. Stock length choice matters more on repeated W16s than almost anywhere else.
Frequently Asked Questions
What is the lightest W16 beam?
The lightest is the W16x26, at 26 lb/ft with a 15.69-inch actual depth and 5.5-inch flange. It's a common infill floor beam in light commercial framing. The next size up is the W16x31.
How deep is a W16 beam?
A W16 is between 15.69 and 16.97 inches deep, depending on weight. The "16" is a nominal depth. Use the actual depth from the AISC Shapes Database for clearances and detailing.
How much does a W16x26 weigh?
A W16x26 weighs 26 pounds per linear foot. A 30-foot piece weighs 780 lb and a 40-foot piece weighs 1,040 lb, before any connection material.
What is the difference between W16x26 and W16x31?
The W16x31 has a thicker flange (0.440 vs 0.345 inch) and about 23% more section modulus, for 5 more pounds per foot. Flange width and depth are nearly the same, so they look alike on a drawing. Read the callout carefully, since mixing them up shifts tonnage quickly on a large floor.
What are W16 beams used for?
Light W16s (26 and 31) are typical floor and roof infill beams. The 7-inch flange group (36 to 57) covers girders and heavier beams, and the 10-inch flange shapes (67 to 100) show up as heavy girders, transfer beams and occasionally columns. The engineer of record makes the final selection.
Bottom line
You can look up any W16 for free on the W16x26 reference page and its siblings. The slow part on a real bid is counting every W16 callout across a plan set and catching the exceptions to "TYP." SteelFlo boxes each callout on every sheet, so you review the count instead of building it.