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How far can an 11-7/8 in I-joist span?
At 16 inches on center, an 11-7/8 in TJI 210 has a published maximum clear span of 19 ft 3 in for 40 psf live + 10 psf dead, L/480. Another TJI series, loading or floor assembly has a different limit. Manufacturer span table.
| TJI series | Max. clear span | Check |
|---|---|---|
| TJI 110 | 18 ft 5 in | Full chart |
| TJI 210 | 19 ft 3 in | Full chart |
| TJI 230 | 19 ft 10 in | Full chart |
| TJI 360 | 20 ft 11 in | Full chart |
| TJI 560 | 23 ft 8 in | Full chart |
These are Weyerhaeuser TJI floor-span examples, not generic I-joist capacities or joist-length recommendations. For a different load case, see other load tables.
Find a TJI size or check your clear span
No JavaScript required for the full span table below. Example: 11-7/8 in TJI 210, 16 in o.c., 40/10 psf, L/480 → 19 ft 3 in. A 19 ft clear span is 3 in below that particular published table limit, subject to all its assumptions.
TJI I-Joist Floor Span Chart — 40/10 psf, L/480
Published maximum clear spans. Weyerhaeuser TJI 110, 210, 230, 360 and 560, 9-1/2 through 16 in depths, with 40 psf live load, 10 psf dead load and L/480 live-load deflection. The manufacturer’s listed installation and support conditions apply. Source: TJ-4000 page 7.
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On a narrow screen, swipe horizontally to see all spacings. The first column identifies the actual TJI depth and series.
| 9-1/2 in · TJI 110 | 16 ft 11 in | 15 ft 6 in | 14 ft 7 in | 13 ft 7 in |
|---|---|---|---|---|
| 9-1/2 in · TJI 210 | 17 ft 9 in | 16 ft 3 in | 15 ft 4 in | 14 ft 3 in |
| 9-1/2 in · TJI 230 | 18 ft 3 in | 16 ft 8 in | 15 ft 9 in | 14 ft 8 in |
| 11-7/8 in · TJI 110 | 20 ft 2 in | 18 ft 5 in | 17 ft 4 in | 15 ft 9 in† |
| 11-7/8 in · TJI 210 | 21 ft 1 in | 19 ft 3 in | 18 ft 2 in | 16 ft 11 in |
| 11-7/8 in · TJI 230 | 21 ft 8 in | 19 ft 10 in | 18 ft 8 in | 17 ft 5 in |
| 11-7/8 in · TJI 360 | 22 ft 11 in | 20 ft 11 in | 19 ft 8 in | 18 ft 4 in |
| 11-7/8 in · TJI 560 | 26 ft 1 in | 23 ft 8 in | 22 ft 4 in | 20 ft 9 in |
| 14 in · TJI 110 | 22 ft 10 in | 20 ft 11 in | 19 ft 2 in | 17 ft 2 in† |
| 14 in · TJI 210 | 23 ft 11 in | 21 ft 10 in | 20 ft 8 in | 18 ft 10 in† |
| 14 in · TJI 230 | 24 ft 8 in | 22 ft 6 in | 21 ft 2 in | 19 ft 9 in† |
| 14 in · TJI 360 | 26 ft 0 in | 23 ft 8 in | 22 ft 4 in | 20 ft 9 in† |
| 14 in · TJI 560 | 29 ft 6 in | 26 ft 10 in | 25 ft 4 in | 23 ft 6 in |
| 16 in · TJI 110 | 25 ft 4 in | 22 ft 6 in | 20 ft 7 in† | 18 ft 1 in† |
| 16 in · TJI 210 | 26 ft 6 in | 24 ft 3 in | 22 ft 6 in† | 19 ft 11 in† |
| 16 in · TJI 230 | 27 ft 3 in | 24 ft 10 in | 23 ft 6 in | 21 ft 1 in† |
| 16 in · TJI 360 | 28 ft 9 in | 26 ft 3 in | 24 ft 8 in† | 21 ft 5 in† |
| 16 in · TJI 560 | 32 ft 8 in | 29 ft 8 in | 28 ft 0 in | 25 ft 2 in† |
Important: the table assumes uniform loads, a glue-nailed single layer of appropriate floor panels, the more restrictive of simple/continuous spans, minimum end bearing 1-3/4 in and intermediate bearing 3-1/2 in. Without subfloor adhesive, reduce spans by 6 in with nails or 12 in with proprietary fasteners. † means conditional web stiffeners can be required for continuous-span joists at intermediate bearings under 5-1/4 in. See the full footnote thresholds. Long-term dead-load creep is not included.
Weyerhaeuser TJ-4000 p7, July 2025. 40 psf live / 10 psf dead; L/480; 18 combinations. The source conditions and design checks apply.
I-Joist Spans for Other Loads and L/360 Deflection
Do not reuse the 40/10, L/480 numbers for another floor loading or deflection criterion. TJ-4000 page 7 separately publishes 40 psf live / 20 psf dead tables and L/360 live-load deflection tables. The example below illustrates why these selections matter.
| Depth / TJI | 40/10, L/480 | 40/20, L/480 | 40/10, L/360 | 40/20, L/360 |
|---|---|---|---|---|
| 9-1/2 in · TJI 110 | 15 ft 6 in | 15 ft 6 in | 17 ft 2 in | 15 ft 8 in |
| 11-7/8 in · TJI 110 | 18 ft 5 in | 17 ft 8 in | 19 ft 4 in | 17 ft 8 in |
| 11-7/8 in · TJI 210 | 19 ft 3 in | 19 ft 3 in | 21 ft 2 in | 19 ft 4 in |
| 14 in · TJI 210 | 21 ft 10 in | 21 ft 1 in | 23 ft 1 in | 21 ft 1 in |
| 16 in · TJI 210 | 24 ft 3 in | 22 ft 6 in | 24 ft 8 in | 22 ft 6 in |
These are selected published examples, not a complete alternate table or approval to choose L/360 in place of L/480. A stricter vibration or serviceability target may still govern. Read all four source tables and footnotes. For 50 psf live loads, multiple floors, heavy finishes, point loads or unusual spans, use the relevant approved design method, manufacturer software and qualified design review.
18–24 Inch Deep I-Joists
Deeper TJI products have a separate manufacturer table with different available series, permitted spacings and bearing details. The following are source examples at 16 in o.c., 40 psf live + 10 psf dead and L/480, from TJ-4000 page 18. Do not insert these values into the 9-1/2 to 16 in checker.
| Depth | Product | Clear span | Additional conditions |
|---|---|---|---|
| 18 in | TJI 360 | 28 ft 8 in | 18/20 in: minimum 1-3/4 in end, 3-1/2 in intermediate |
| 18 in | TJI 560 / 560D | 32 ft 5 in | Check web stiffener footnote and configuration |
| 20 in | TJI 360 | 31 ft 0 in | Check web stiffener footnote and configuration |
| 20 in | TJI 560 / 560D | 35 ft 1 in | Check web stiffener footnote and configuration |
| 22 in | TJI 560D | 37 ft 11 in | Web stiffeners required at all bearings |
| 24 in | TJI 560D | 40 ft 6 in | Web stiffeners required at all bearings |
Deep members can require web stiffeners at intermediate bearings, and 22–24 in TJI 560D joists require stiffeners at all bearings per the guide. Deep TJI 560 and 560D are different product designations. Check the full page 18 table, the bearing arrangement, installation and the manufacturer’s current regional product literature.
How to Measure Clear Span, Joist Depth and On-Center Spacing
Clear span is measured horizontally between the inside faces of adequate bearing supports—not the overall joist cut length, outside-to-outside building dimension or purchased board length. An I-joist needs its specified length on the bearing surfaces as well as the clear span between them.
Joist depth is the total height from the top of the top flange to the underside of the bottom flange. On-center spacing is centerline-to-centerline between adjacent joists, not the gap between flange edges. A nominal 16 in o.c. spacing says nothing by itself about the joist depth or TJI series.
Worked example: a floor has 19 ft between support faces, TJI 210 members at 11-7/8 in depth and 16 in o.c. The 40/10, L/480 source cell is 19 ft 3 in. The member is 3 in under that published table span; the required design and installation checks still apply.
Installation Conditions That Can Change the Answer
Loads: the primary chart assumes uniform 40 psf floor live load and 10 psf dead load. A refrigerator-sized point load, a heavy stone floor, partition walls, concentrated machinery, storage, bath fixtures or more demanding occupancy may require another analysis. Do not substitute a span table for a project-specific load path.
Bearings and continuous spans: the source uses a minimum of 1-3/4 in bearing at ends and 3-1/2 in at intermediate supports, subject to all guide details. On continuous joists, the short-to-long span ratio should be at least 0.4 to avoid uplift. Its † footnote may require intermediate web stiffeners where bearing is shorter than 5-1/4 in and the neighboring span exceeds a series-specific threshold. See the threshold table on page 7.
Subfloor and vibration: the chart assumes specified 24 in span-rated glue-nailed floor panels for composite action in the deflection calculation. Without adhesive, the guide reduces listed spans by 6 in with nails or by 12 in with proprietary fasteners. Passing L/480 does not guarantee acceptable floor vibration or long-term dead-load creep performance. Weyerhaeuser’s TJI design resources include additional floor performance information.
Holes, flanges and support detailing: permitted web openings depend on joist series, hole size and location; never cut a flange to route services. Hangers, blocking, rim boards, bracing, seismic and fire requirements must be evaluated separately. Temporary unbraced I-joists can be unstable during construction. Use the hole rules and floor framing instructions for your specific installation.
The chart covers floor members under one published reference. Roof slopes, snow, wind, cantilevers, multiple-point loads or unusual bearing and fastening conditions need separate design tables or software.
TJI vs BCI and Other I-Joist Manufacturers
TJI is Weyerhaeuser’s product family, not a universal grade name for wood I-joists. Another manufacturer’s 11-7/8 in I-joist does not inherit the TJI 210 or TJI 560 span values merely because it has the same overall depth. Flange materials, web thickness, stiffness, resistance, bearing and hanger details can differ.
For Boise Cascade BCI / AJS products, use the company’s regional I-joist span and specifier guides and its BC Calc design resource. For an unidentified I-joist, locate its manufacturer stamp and current documentation before choosing any table. Regional versions, model generations and product availability can also matter.
If you’re comparing ordinary sawn lumber rather than engineered wood, use the Floor Joist Span Chart. For LVL beams, see the LVL Span Chart; beams and joists are different design problems.
I-Joist Span Chart FAQs
How far can an 11-7/8 inch I-joist span at 16 inches on center?
For this Weyerhaeuser 40/10 psf, L/480 table, 11-7/8 in deep TJI 110, 210, 230, 360 and 560 list 18 ft 5 in, 19 ft 3 in, 19 ft 10 in, 20 ft 11 in and 23 ft 8 in respectively. Other loads, joists or installation conditions change the answer.
Can an I-joist span 20 feet?
Some listed depth and series combinations reach a 20 ft clear span at 16 in o.c. in this source table; others do not. At 11-7/8 in depth, TJI 360 lists 20 ft 11 in while TJI 210 lists 19 ft 3 in. These are preliminary source-table comparisons.
What is the maximum span for a 14-inch TJI joist?
There is no single maximum: it depends on series, on-center spacing, design loads, deflection and floor details. For example, a 14 in TJI 210 at 16 in o.c. lists 21 ft 10 in under this 40/10, L/480 source.
Are the I-joist span charts the same for 40/10 and 40/20 loads?
No. The manufacturer publishes separate values. In the source at 16 in o.c., a 14 in TJI 210 shows 21 ft 10 in for 40/10 L/480 and 21 ft 1 in for 40/20 L/480.
What is the difference between L/360 and L/480?
They are different live-load deflection limits, expressed as the span divided by 360 or 480. L/480 is more restrictive on live-load deflection alone, but the manufacturer also checks strength and other criteria. Do not choose L/360 without confirming its suitability for the specific project.
Is clear span the same as overall joist length?
No. Clear span is measured between inside support faces. The overall joist includes bearing portions and can be longer than the clear span.
Can I use a TJI span chart for Boise Cascade BCI or another brand?
No. Use the exact product manufacturer, series, regional span guide and engineering specifications. Similar depths are not proof of equal structural capacity.
Can I drill holes through the web of an I-joist?
Holes may be permitted under the correct manufacturer hole chart for the joist type, position and dimensions. Do not cut or notch the flange; this span lookup does not verify a field modification.
Does the guide require web stiffeners?
Sometimes. Certain marked cells carry a continuous-span intermediate-bearing footnote, with specific threshold spans and conditions. Deeper 22–24 in TJI 560D products have separate bearing-stiffener requirements.
Are floor spans the same as roof spans or cantilever capacities?
No. Roof framing has separate load combinations and installation conditions. Cantilevers, point loads, supporting walls and roof conditions require the corresponding design method and manufacturer details.
Sources and Calculation Basis
Primary reference: Weyerhaeuser TJ-4000 Specifier’s Guide (July 2025), page 7. The full 18-row 40 psf live / 10 psf dead, L/480 span table on this page preserves the specified source values in feet and inches; the finder reads those rows directly and does not interpolate or invent capacities. Other-load examples are selectively drawn from the same page. Deep-joist examples come from page 18.
Additional references: Weyerhaeuser TJI product and design resources for current product documentation; Boise Cascade regional BCI/AJS span charts for other manufacturers’ joists; and APA engineered I-joist resources for general installation context. These sources do not mean that different manufacturers’ products are interchangeable.
Source check: October 29, 2026. Always compare against the manufacturer document, edition and design requirements that govern your project. This resource is not engineering approval or construction instructions for an unbraced floor system.