Code and standard reference
AWC Span Tables Explained
Last reviewed · BuildMath editorial team
AWC span tables require more than member depth: select species, grade, spacing, live load, dead load, deflection limit, and use condition before reading an allowable span. BuildMath shows conservative comparison rows and a planning ratio, but the current AWC resource, adopted IRC table, bearing, connections, and a qualified engineer govern the final member.
Limit table
| Item | Limit or rule | Reference | Verification note |
|---|---|---|---|
| Species and grade | Select the actual stamp | AWC input | Do not assume all 2×10 material has the same strength. |
| Spacing | 12, 16, 19.2, or 24 in o.c. as applicable | AWC input | Closer spacing can increase allowable span. |
| Live and dead load | Use project-specific loads | AWC input | Snow, storage, finishes, and occupancy affect selection. |
| Deflection | Select the required limit | AWC input | Strength alone does not control serviceability. |
| Bearing and connections | Check separately | IRC/AWC details | A span result does not size hangers, fasteners, or bearing. |
How to use this code summary
- Confirm which code edition and local amendment applies to the project address.
- Measure the actual completed geometry, not only rough framing or nominal dimensions.
- Compare the calculator output with every relevant row and exception in the primary source.
- Escalate structural, accessibility, egress, guard, and fall-protection questions to the authority or qualified professional.
Calculators that use this reference
American Wood Council span resources
Related code references
Frequently asked questions
Is this the complete code text?
No. This is a focused planning summary with a direct primary-source link. Definitions, exceptions, local amendments, and adjacent sections can change how a limit applies.
Which edition should I use?
Use the edition adopted by the authority having jurisdiction for the project address, including local amendments.
Can the calculator certify compliance?
No. It can flag a value against a displayed planning limit, but approval belongs to the authority, designer, or qualified professional.
Why is the source linked?
The source link lets readers and answer engines distinguish a cited rule from an unsupported numerical claim.
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