// CODE SNIPPET
2308.4 Floor Framing
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Floor framing shall comply with this section.
Girders for single-story construction or girders supporting loads from a single floor shall be not less than 4 inches by 6 inches (102 mm by 152 mm) for spans 6 feet (1829 mm) or less, provided that girders are spaced not more than 8 feet (2438 mm) on center. Other girders shall be designed to support the loads specified in this code. Girder end joints shall occur over supports.
Where a girder is spliced over a support, an adequate tie shall be provided. The ends of beams or girders supported on masonry or concrete shall not have less than 3 inches (76 mm) of bearing.
The allowable spans of girders that are fabricated of dimension lumber shall not exceed the values set forth in Table 2308.4.1.1(1) or 2308.4.1.1(2).
HEADER AND GIRDER SPANSa, b FOR EXTERIOR BEARING WALLS (Maximum spans for Douglas fir-larch, hem-fir, Southern pine and spruce-pine-fir and required number of jack studs)
| GIRDERS AND HEADERS SUPPORTING | SIZE | GROUND SNOW LOAD (psf)e | |||||||||||||||||
| 30 | 50 | 70 | |||||||||||||||||
| Building widthc (feet) | |||||||||||||||||||
| 12 | 24 | 36 | 12 | 24 | 36 | 12 | 24 | 36 | |||||||||||
| Spanf | NJd | Spanf | NJd | Spanf | NJd | Spanf | NJd | Spanf | NJd | Spanf | NJd | Spanf | NJd | Spanf | NJd | Spanf | NJd | ||
| Roof and ceiling | 1-2 × 6 | 4-0 | 1 | 3-1 | 2 | 2-7 | 2 | 3-5 | 1 | 2-8 | 2 | 2-3 | 2 | 3-0 | 2 | 2-4 | 2 | 2-0 | 2 |
| 1-2 × 8 | 5-1 | 2 | 3-11 | 2 | 3-3 | 2 | 4-4 | 2 | 3-4 | 2 | 2-10 | 2 | 3-10 | 2 | 3-0 | 2 | 2-6 | 3 | |
| 1-2 × 10 | 6-0 | 2 | 4-8 | 2 | 3-11 | 2 | 5-2 | 2 | 4-0 | 2 | 3-4 | 3 | 4-7 | 2 | 3-6 | 3 | 3-0 | 3 | |
| 1-2 × 12 | 7-1 | 2 | 5-5 | 2 | 4-7 | 3 | 6-1 | 2 | 4-8 | 3 | 3-11 | 3 | 5-5 | 2 | 4-2 | 3 | 3-6 | 3 | |
| 2-2 × 4 | 4-0 | 1 | 3-1 | 1 | 2-7 | 1 | 3-5 | 1 | 2-7 | 1 | 2-2 | 1 | 3-0 | 1 | 2-4 | 1 | 2-0 | 1 | |
| 2-2 × 6 | 6-0 | 1 | 4-7 | 1 | 3-10 | 1 | 5-1 | 1 | 3-11 | 1 | 3-3 | 2 | 4-6 | 1 | 3-6 | 2 | 2-11 | 2 | |
| 2-2 × 8 | 7-7 | 1 | 5-9 | 1 | 4-10 | 2 | 6-5 | 1 | 5-0 | 2 | 4-2 | 2 | 5-9 | 1 | 4-5 | 2 | 3-9 | 2 | |
| 2-2 × 10 | 9-0 | 1 | 6-10 | 2 | 5-9 | 2 | 7-8 | 2 | 5-11 | 2 | 4-11 | 2 | 6-9 | 2 | 5-3 | 2 | 4-5 | 2 | |
| 2-2 × 12 | 10-7 | 2 | 8-1 | 2 | 6-10 | 2 | 9-0 | 2 | 6-11 | 2 | 5-10 | 2 | 8-0 | 2 | 6-2 | 2 | 5-2 | 3 | |
| 3-2 × 8 | 9-5 | 1 | 7-3 | 1 | 6-1 | 1 | 8-1 | 1 | 6-3 | 1 | 5-3 | 2 | 7-2 | 1 | 5-6 | 2 | 4-8 | 2 | |
| 3-2 × 10 | 11-3 | 1 | 8-7 | 1 | 7-3 | 2 | 9-7 | 1 | 7-4 | 2 | 6-2 | 2 | 8-6 | 1 | 6-7 | 2 | 5-6 | 2 | |
| 3-2 × 12 | 13-2 | 1 | 10-1 | 2 | 8-6 | 2 | 11-3 | 2 | 8-8 | 2 | 7-4 | 2 | 10-0 | 2 | 7-9 | 2 | 6-6 | 2 | |
| 4-2 × 8 | 10-11 | 1 | 8-4 | 1 | 7-0 | 1 | 9-4 | 1 | 7-2 | 1 | 6-0 | 1 | 8-3 | 1 | 6-4 | 1 | 5-4 | 2 | |
| 4-2 × 10 | 12-11 | 1 | 9-11 | 1 | 8-4 | 1 | 11-1 | 1 | 8-6 | 1 | 7-2 | 2 | 9-10 | 1 | 7-7 | 2 | 6-4 | 2 | |
| 4-2 × 12 | 15-3 | 1 | 11-8 | 1 | 9-10 | 2 | 13-0 | 1 | 10-0 | 2 | 8-5 | 2 | 11-7 | 1 | 8-11 | 2 | 7-6 | 2 | |
| Roof, ceiling and one center-bearing floor | 1-2 × 6 | 3-3 | 1 | 2-7 | 2 | 2-2 | 2 | 3-0 | 2 | 2-4 | 2 | 2-0 | 2 | 2-9 | 2 | 2-2 | 2 | 1-10 | 2 |
| 1-2 × 8 | 4-1 | 2 | 3-3 | 2 | 2-9 | 2 | 3-9 | 2 | 3-0 | 2 | 2-6 | 3 | 3-6 | 2 | 2-9 | 2 | 2-4 | 3 | |
| 1-2 × 10 | 4-11 | 2 | 3-10 | 2 | 3-3 | 3 | 4-6 | 2 | 3-6 | 3 | 3-0 | 3 | 4-1 | 2 | 3-3 | 3 | 2-9 | 3 | |
| 1-2 × 12 | 5-9 | 2 | 4-6 | 3 | 3-10 | 3 | 5-3 | 2 | 4-2 | 3 | 3-6 | 3 | 4-10 | 3 | 3-10 | 3 | 3-3 | 4 | |
| 2-2 × 4 | 3-3 | 1 | 2-6 | 1 | 2-2 | 1 | 3-0 | 1 | 2-4 | 1 | 2-0 | 1 | 2-8 | 1 | 2-2 | 1 | 1-10 | 1 | |
| 2-2 × 6 | 4-10 | 1 | 3-9 | 1 | 3-3 | 2 | 4-5 | 1 | 3-6 | 2 | 3-0 | 2 | 4-1 | 1 | 3-3 | 2 | 2-9 | 2 | |
| 2-2 × 8 | 6-1 | 1 | 4-10 | 2 | 4-1 | 2 | 5-7 | 2 | 4-5 | 2 | 3-9 | 2 | 5-2 | 2 | 4-1 | 2 | 3-6 | 2 | |
| 2-2 × 10 | 7-3 | 2 | 5-8 | 2 | 4-10 | 2 | 6-8 | 2 | 5-3 | 2 | 4-5 | 2 | 6-1 | 2 | 4-10 | 2 | 4-1 | 2 | |
| 2-2 × 12 | 8-6 | 2 | 6-8 | 2 | 5-8 | 2 | 7-10 | 2 | 6-2 | 2 | 5-3 | 3 | 7-2 | 2 | 5-8 | 2 | 4-10 | 3 | |
| 3-2 × 8 | 7-8 | 1 | 6-0 | 1 | 5-1 | 2 | 7-0 | 1 | 5-6 | 2 | 4-8 | 2 | 6-5 | 1 | 5-1 | 2 | 4-4 | 2 | |
| 3-2 × 10 | 9-1 | 1 | 7-2 | 2 | 6-1 | 2 | 8-4 | 1 | 6-7 | 2 | 5-7 | 2 | 7-8 | 2 | 6-1 | 2 | 5-2 | 2 | |
| 3-2 × 12 | 10-8 | 2 | 8-5 | 2 | 7-2 | 2 | 9-10 | 2 | 7-8 | 2 | 6-7 | 2 | 9-0 | 2 | 7-1 | 2 | 6-1 | 2 | |
| 4-2 × 8 | 8-10 | 1 | 6-11 | 1 | 5-11 | 1 | 8-1 | 1 | 6-4 | 1 | 5-5 | 2 | 7-5 | 1 | 5-11 | 1 | 5-0 | 2 | |
| 4-2 × 10 | 10-6 | 1 | 8-3 | 2 | 7-0 | 2 | 9-8 | 1 | 7-7 | 2 | 6-5 | 2 | 8-10 | 1 | 7-0 | 2 | 6-0 | 2 | |
| 4-2 × 12 | 12-4 | 1 | 9-8 | 2 | 8-3 | 2 | 11-4 | 2 | 8-11 | 2 | 7-7 | 2 | 10-4 | 2 | 8-3 | 2 | 7-0 | 2 | |
| Roof, ceiling and one clear span floor | 1-2 × 6 | 2-11 | 2 | 2-3 | 2 | 1-11 | 2 | 2-9 | 2 | 2-1 | 2 | 1-9 | 2 | 2-7 | 2 | 2-0 | 2 | 1-8 | 2 |
| 1-2 × 8 | 3-9 | 2 | 2-10 | 2 | 2-5 | 3 | 3-6 | 2 | 2-8 | 2 | 2-3 | 3 | 3-3 | 2 | 2-6 | 3 | 2-2 | 3 | |
| 1-2 × 10 | 4-5 | 2 | 3-5 | 3 | 2-10 | 3 | 4-2 | 2 | 3-2 | 3 | 2-8 | 3 | 3-11 | 2 | 3-0 | 3 | 2-6 | 3 | |
| 1-2 × 12 | 5-2 | 2 | 4-0 | 3 | 3-4 | 3 | 4-10 | 3 | 3-9 | 3 | 3-2 | 4 | 4-7 | 3 | 3-6 | 3 | 3-0 | 4 | |
| 2-2 × 4 | 2-11 | 1 | 2-3 | 1 | 1-10 | 1 | 2-9 | 1 | 2-1 | 1 | 1-9 | 1 | 2-7 | 1 | 2-0 | 1 | 1-8 | 1 | |
| 2-2 × 6 | 4-4 | 1 | 3-4 | 2 | 2-10 | 2 | 4-1 | 1 | 3-2 | 2 | 2-8 | 2 | 3-10 | 1 | 3-0 | 2 | 2-6 | 2 | |
| 2-2 × 8 | 5-6 | 2 | 4-3 | 2 | 3-7 | 2 | 5-2 | 2 | 4-0 | 2 | 3-4 | 2 | 4-10 | 2 | 3-9 | 2 | 3-2 | 2 | |
| 2-2 × 10 | 6-7 | 2 | 5-0 | 2 | 4-2 | 2 | 6-1 | 2 | 4-9 | 2 | 4-0 | 2 | 5-9 | 2 | 4-5 | 2 | 3-9 | 3 | |
| 2-2 × 12 | 7-9 | 2 | 5-11 | 2 | 4-11 | 3 | 7-2 | 2 | 5-7 | 2 | 4-8 | 3 | 6-9 | 2 | 5-3 | 3 | 4-5 | 3 | |
| 3-2 × 8 | 6-11 | 1 | 5-3 | 2 | 4-5 | 2 | 6-5 | 1 | 5-0 | 2 | 4-2 | 2 | 6-1 | 1 | 4-8 | 2 | 4-0 | 2 | |
| 3-2 × 10 | 8-3 | 2 | 6-3 | 2 | 5-3 | 2 | 7-8 | 2 | 5-11 | 2 | 5-0 | 2 | 7-3 | 2 | 5-7 | 2 | 4-8 | 2 | |
| 3-2 × 12 | 9-8 | 2 | 7-5 | 2 | 6-2 | 2 | 9-0 | 2 | 7-0 | 2 | 5-10 | 2 | 8-6 | 2 | 6-7 | 2 | 5-6 | 3 | |
| 4-2 × 8 | 8-0 | 1 | 6-1 | 1 | 5-1 | 2 | 7-5 | 1 | 5-9 | 2 | 4-10 | 2 | 7-0 | 1 | 5-5 | 2 | 4-7 | 2 | |
| 4-2 × 10 | 9-6 | 1 | 7-3 | 2 | 6-1 | 2 | 8-10 | 1 | 6-10 | 2 | 5-9 | 2 | 8-4 | 1 | 6-5 | 2 | 5-5 | 2 | |
| 4-2 × 12 | 11-2 | 2 | 8-6 | 2 | 7-2 | 2 | 10-5 | 2 | 8-0 | 2 | 6-9 | 2 | 9-10 | 2 | 7-7 | 2 | 6-5 | 2 | |
| Roof, ceiling and two center-bearing floors | 1-2 × 6 | 2-8 | 2 | 2-1 | 2 | 1-10 | 2 | 2-7 | 2 | 2-0 | 2 | 1-9 | 2 | 2-5 | 2 | 1-11 | 2 | 1-8 | 2 |
| 1-2 × 8 | 3-5 | 2 | 2-8 | 2 | 2-4 | 3 | 3-3 | 2 | 2-7 | 2 | 2-2 | 3 | 3-1 | 2 | 2-5 | 3 | 2-1 | 3 | |
| 1-2 × 10 | 4-0 | 2 | 3-2 | 3 | 2-9 | 3 | 3-10 | 2 | 3-1 | 3 | 2-7 | 3 | 3-8 | 2 | 2-11 | 3 | 2-5 | 3 | |
| 1-2 × 12 | 4-9 | 3 | 3-9 | 3 | 3-2 | 4 | 4-6 | 3 | 3-7 | 3 | 3-1 | 4 | 4-3 | 3 | 3-5 | 3 | 2-11 | 4 | |
| 2-2 × 4 | 2-8 | 1 | 2-1 | 1 | 1-9 | 1 | 2-6 | 1 | 2-0 | 1 | 1-8 | 1 | 2-5 | 1 | 1-11 | 1 | 1-7 | 1 | |
| 2-2 × 6 | 4-0 | 1 | 3-2 | 2 | 2-8 | 2 | 3-9 | 1 | 3-0 | 2 | 2-7 | 2 | 3-7 | 1 | 2-10 | 2 | 2-5 | 2 | |
| 2-2 × 8 | 5-0 | 2 | 4-0 | 2 | 3-5 | 2 | 4-10 | 2 | 3-10 | 2 | 3-3 | 2 | 4-7 | 2 | 3-7 | 2 | 3-1 | 2 | |
| 2-2 × 10 | 6-0 | 2 | 4-9 | 2 | 4-0 | 2 | 5-8 | 2 | 4-6 | 2 | 3-10 | 3 | 5-5 | 2 | 4-3 | 2 | 3-8 | 3 | |
| 2-2 × 12 | 7-0 | 2 | 5-7 | 2 | 4-9 | 3 | 6-8 | 2 | 5-4 | 3 | 4-6 | 3 | 6-4 | 2 | 5-0 | 3 | 4-3 | 3 | |
| 3-2 × 8 | 6-4 | 1 | 5-0 | 2 | 4-3 | 2 | 6-0 | 1 | 4-9 | 2 | 4-1 | 2 | 5-8 | 2 | 4-6 | 2 | 3-10 | 2 | |
| 3-2 × 10 | 7-6 | 2 | 5-11 | 2 | 5-1 | 2 | 7-1 | 2 | 5-8 | 2 | 4-10 | 2 | 6-9 | 2 | 5-4 | 2 | 4-7 | 2 | |
| 3-2 × 12 | 8-10 | 2 | 7-0 | 2 | 5-11 | 2 | 8-5 | 2 | 6-8 | 2 | 5-8 | 3 | 8-0 | 2 | 6-4 | 2 | 5-4 | 3 | |
| 4-2 × 8 | 7-3 | 1 | 5-9 | 1 | 4-11 | 2 | 6-11 | 1 | 5-6 | 2 | 4-8 | 2 | 6-7 | 1 | 5-2 | 2 | 4-5 | 2 | |
| 4-2 × 10 | 8-8 | 1 | 6-10 | 2 | 5-10 | 2 | 8-3 | 2 | 6-6 | 2 | 5-7 | 2 | 7-10 | 2 | 6-2 | 2 | 5-3 | 2 | |
| 4-2 × 12 | 10-2 | 2 | 8-1 | 2 | 6-10 | 2 | 9-8 | 2 | 7-8 | 2 | 6-7 | 2 | 9-2 | 2 | 7-3 | 2 | 6-2 | 2 | |
| Roof, ceiling and two clear span floors | 1-2 × 6 | 2-3 | 2 | 1-9 | 2 | 1-5 | 2 | 2-3 | 2 | 1-9 | 2 | 1-5 | 3 | 2-2 | 2 | 1-8 | 2 | 1-5 | 3 |
| 1-2 × 8 | 2-10 | 2 | 2-2 | 3 | 1-10 | 3 | 2-10 | 2 | 2-2 | 3 | 1-10 | 3 | 2-9 | 2 | 2-1 | 3 | 1-10 | 3 | |
| 1-2 × 10 | 3-4 | 2 | 2-7 | 3 | 2-2 | 3 | 3-4 | 3 | 2-7 | 3 | 2-2 | 4 | 3-3 | 3 | 2-6 | 3 | 2-2 | 4 | |
| 1-2 × 12 | 4-0 | 3 | 3-0 | 3 | 2-7 | 4 | 4-0 | 3 | 3-0 | 4 | 2-7 | 4 | 3-10 | 3 | 3-0 | 4 | 2-6 | 4 | |
| 2-2 × 4 | 2-3 | 1 | 1-8 | 1 | 1-4 | 1 | 2-3 | 1 | 1-8 | 1 | 1-4 | 1 | 2-2 | 1 | 1-8 | 1 | 1-4 | 2 | |
| 2-2 × 6 | 3-4 | 1 | 2-6 | 2 | 2-2 | 2 | 3-4 | 2 | 2-6 | 2 | 2-2 | 2 | 3-3 | 2 | 2-6 | 2 | 2-1 | 2 | |
| 2-2 × 8 | 4-3 | 2 | 3-3 | 2 | 2-8 | 2 | 4-3 | 2 | 3-3 | 2 | 2-8 | 2 | 4-1 | 2 | 3-2 | 2 | 2-8 | 3 | |
| 2-2 × 10 | 5-0 | 2 | 3-10 | 2 | 3-2 | 3 | 5-0 | 2 | 3-10 | 2 | 3-2 | 3 | 4-10 | 2 | 3-9 | 3 | 3-2 | 3 | |
| 2-2 × 12 | 5-11 | 2 | 4-6 | 3 | 3-9 | 3 | 5-11 | 2 | 4-6 | 3 | 3-9 | 3 | 5-8 | 2 | 4-5 | 3 | 3-9 | 3 | |
| 3-2 × 8 | 5-3 | 1 | 4-0 | 2 | 3-5 | 2 | 5-3 | 2 | 4-0 | 2 | 3-5 | 2 | 5-1 | 2 | 3-11 | 2 | 3-4 | 2 | |
| 3-2 × 10 | 6-3 | 2 | 4-9 | 2 | 4-0 | 2 | 6-3 | 2 | 4-9 | 2 | 4-0 | 2 | 6-1 | 2 | 4-8 | 2 | 4-0 | 3 | |
| 3-2 × 12 | 7-5 | 2 | 5-8 | 2 | 4-9 | 3 | 7-5 | 2 | 5-8 | 2 | 4-9 | 3 | 7-2 | 2 | 5-6 | 3 | 4-8 | 3 | |
| 4-2 × 8 | 6-1 | 1 | 4-8 | 2 | 3-11 | 2 | 6-1 | 1 | 4-8 | 2 | 3-11 | 2 | 5-11 | 1 | 4-7 | 2 | 3-10 | 2 | |
| 4-2 × 10 | 7-3 | 2 | 5-6 | 2 | 4-8 | 2 | 7-3 | 2 | 5-6 | 2 | 4-8 | 2 | 7-0 | 2 | 5-5 | 2 | 4-7 | 2 | |
| 4-2 × 12 | 8-6 | 2 | 6-6 | 2 | 5-6 | 2 | 8-6 | 2 | 6-6 | 2 | 5-6 | 2 | 8-3 | 2 | 6-4 | 2 | 5-4 | 3 | |
For SI: 1 inch = 25.4 mm, 1 pound per square foot = 0.0479 kPa.
- Spans are given in feet and inches.
- Spans are based on minimum design properties for No. 2 grade lumber of Douglas fir-larch, hem-fir, Southern pine and spruce-pine fir.
- Building width is measured perpendicular to the ridge. For widths between those shown, spans are permitted to be interpolated.
- NJ = Number of jack studs required to support each end. Where the number of required jack studs equals one, the header is permitted to be supported by an approved framing anchor attached to the full-height wall stud and to the header.
- Use 30 psf ground snow load for cases in which ground snow load is less than 30 psf and the roof live load is equal to or less than 20 psf.
- Spans are calculated assuming the top of the header or girder is laterally braced by perpendicular framing. Where the top of the header or girder is not laterally braced (for example, cripple studs bearing on the header), tabulated spans for headers consisting of 2 × 8, 2 × 10, or 2 × 12 sizes shall be multiplied by 0.70 or the header or girder shall be designed.
HEADER AND GIRDER SPANSa, b FOR INTERIOR BEARING WALLS (Maximum spans for Douglas fir-larch, hem-fir, Southern pine and spruce-pine-fir and required number of jack studs)
| HEADERS AND GIRDERS SUPPORTING | SIZE | BUILDING WIDTHc (feet) | |||||
| 12 | 24 | 36 | |||||
| Spane | NJd | Spane | NJd | Spane | NJd | ||
| One floor only | 2-2 × 4 | 4-1 | 1 | 2-10 | 1 | 2-4 | 1 |
| 2-2 × 6 | 6-1 | 1 | 4-4 | 1 | 3-6 | 1 | |
| 2-2 × 8 | 7-9 | 1 | 5-5 | 1 | 4-5 | 2 | |
| 2-2 × 10 | 9-2 | 1 | 6-6 | 2 | 5-3 | 2 | |
| 2-2 × 12 | 10-9 | 1 | 7-7 | 2 | 6-3 | 2 | |
| 3-2 × 8 | 9-8 | 1 | 6-10 | 1 | 5-7 | 1 | |
| 3-2 × 10 | 11-5 | 1 | 8-1 | 1 | 6-7 | 2 | |
| 3-2 × 12 | 13-6 | 1 | 9-6 | 2 | 7-9 | 2 | |
| 4-2 × 8 | 11-2 | 1 | 7-11 | 1 | 6-5 | 1 | |
| 4-2 × 10 | 13-3 | 1 | 9-4 | 1 | 7-8 | 1 | |
| 4-2 × 12 | 15-7 | 1 | 11-0 | 1 | 9-0 | 2 | |
| Two floors | 2-2 × 4 | 2-7 | 1 | 1-11 | 1 | 1-7 | 1 |
| 2-2 × 6 | 3-11 | 1 | 2-11 | 2 | 2-5 | 2 | |
| 2-2 × 8 | 5-0 | 1 | 3-8 | 2 | 3-1 | 2 | |
| 2-2 × 10 | 5-11 | 2 | 4-4 | 2 | 3-7 | 2 | |
| 2-2 × 12 | 6-11 | 2 | 5-2 | 2 | 4-3 | 3 | |
| 3-2 × 8 | 6-3 | 1 | 4-7 | 2 | 3-10 | 2 | |
| 3-2 × 10 | 7-5 | 1 | 5-6 | 2 | 4-6 | 2 | |
| 3-2 × 12 | 8-8 | 2 | 6-5 | 2 | 5-4 | 2 | |
| 4-2 × 8 | 7-2 | 1 | 5-4 | 1 | 4-5 | 2 | |
| 4-2 × 10 | 8-6 | 1 | 6-4 | 2 | 5-3 | 2 | |
| 4-2 × 12 | 10-1 | 1 | 7-5 | 2 | 6-2 | 2 | |
For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm.
- Spans are given in feet and inches.
- Spans are based on minimum design properties for No. 2 grade lumber of Douglas fir-larch, hem-fir, Southern pine and spruce-pine fir.
- Building width is measured perpendicular to the ridge. For widths between those shown, spans are permitted to be interpolated.
- NJ = Number of jack studs required to support each end. Where the number of required jack studs equals one, the header is permitted to be supported by an approved framing anchor attached to the full-height wall stud and to the header.
- Spans are calculated assuming the top of the header or girder is laterally braced by perpendicular framing. Where the top of the header or girder is not laterally braced (for example, cripple studs bearing on the header), tabulated spans for headers consisting of 2 × 8, 2 × 10, or 2 × 12 sizes shall be multiplied by 0.70 or the header or girder shall be designed.
Floor joists shall comply with this section.