Header and girder spans (2021 IRC)
A two-ply 2×10 header in an exterior bearing wall supporting roof and ceiling spans up to 6’10” at 30 psf ground snow and a 24-foot building width, and requires 2 jack studs at each end, per 2021 IRC Table R602.7(1).
How to read these tables
The size column pairs a ply count with a lumber size. “2-2×10” means two 2×10s fastened together; a 3-2×12 is three 2×12s fastened together. On this page the same rows are printed as “2 × 2×10”.
NJ is the number of jack studs required at each end of the header, and it is printed next to each span here as “(2 jacks)”. The tables also assume the top of the header is laterally braced — both are facts of the table, stated in its footnotes.
Building width is measured perpendicular to the ridge. Where the ground snow load is less than 30 psf and the roof live load is 20 psf or less, the table’s own instruction is to use the 30 psf ground snow columns.
Point loads, cantilevers beyond the table footnotes, unusual snow loads, or anything else outside the table's stated conditions — that's an engineer's question.
Exterior bearing walls
2021 IRC Table R602.7(1), one table per supporting condition. Columns are ground snow load in psf by building width in feet; each cell is the allowable span with the jack studs required at each end.
Supporting roof and ceiling
| Header | 30 psf ground snow | 50 psf ground snow | 70 psf ground snow | ||||||
|---|---|---|---|---|---|---|---|---|---|
| 12 ft wide | 24 ft wide | 36 ft wide | 12 ft wide | 24 ft wide | 36 ft wide | 12 ft wide | 24 ft wide | 36 ft wide | |
| 1 × 2×6 | 4’0” (1 jack) | 3’1” (2 jacks) | 2’7” (2 jacks) | 3’5” (1 jack) | 2’8” (2 jacks) | 2’3” (2 jacks) | 3’0” (2 jacks) | 2’4” (2 jacks) | 2’0” (2 jacks) |
| 1 × 2×8 | 5’1” (2 jacks) | 3’11” (2 jacks) | 3’3” (2 jacks) | 4’4” (2 jacks) | 3’4” (2 jacks) | 2’10” (2 jacks) | 3’10” (2 jacks) | 3’0” (2 jacks) | 2’6” (3 jacks) |
| 1 × 2×10 | 6’0” (2 jacks) | 4’8” (2 jacks) | 3’11” (2 jacks) | 5’2” (2 jacks) | 4’0” (2 jacks) | 3’4” (3 jacks) | 4’7” (2 jacks) | 3’6” (3 jacks) | 3’0” (3 jacks) |
| 1 × 2×12 | 7’1” (2 jacks) | 5’5” (2 jacks) | 4’7” (3 jacks) | 6’1” (2 jacks) | 4’8” (3 jacks) | 3’11” (3 jacks) | 5’5” (2 jacks) | 4’2” (3 jacks) | 3’6” (3 jacks) |
| 2 × 2×4 | 4’0” (1 jack) | 3’1” (1 jack) | 2’7” (1 jack) | 3’5” (1 jack) | 2’7” (1 jack) | 2’2” (1 jack) | 3’0” (1 jack) | 2’4” (1 jack) | 2’0” (1 jack) |
| 2 × 2×6 | 6’0” (1 jack) | 4’7” (1 jack) | 3’10” (1 jack) | 5’1” (1 jack) | 3’11” (1 jack) | 3’3” (2 jacks) | 4’6” (1 jack) | 3’6” (2 jacks) | 2’11” (2 jacks) |
| 2 × 2×8 | 7’7” (1 jack) | 5’9” (1 jack) | 4’10” (2 jacks) | 6’5” (1 jack) | 5’0” (2 jacks) | 4’2” (2 jacks) | 5’9” (1 jack) | 4’5” (2 jacks) | 3’9” (2 jacks) |
| 2 × 2×10 | 9’0” (1 jack) | 6’10” (2 jacks) | 5’9” (2 jacks) | 7’8” (2 jacks) | 5’11” (2 jacks) | 4’11” (2 jacks) | 6’9” (2 jacks) | 5’3” (2 jacks) | 4’5” (2 jacks) |
| 2 × 2×12 | 10’7” (2 jacks) | 8’1” (2 jacks) | 6’10” (2 jacks) | 9’0” (2 jacks) | 6’11” (2 jacks) | 5’10” (2 jacks) | 8’0” (2 jacks) | 6’2” (2 jacks) | 5’2” (3 jacks) |
| 3 × 2×8 | 9’5” (1 jack) | 7’3” (1 jack) | 6’1” (1 jack) | 8’1” (1 jack) | 6’3” (1 jack) | 5’3” (2 jacks) | 7’2” (1 jack) | 5’6” (2 jacks) | 4’8” (2 jacks) |
| 3 × 2×10 | 11’3” (1 jack) | 8’7” (1 jack) | 7’3” (2 jacks) | 9’7” (1 jack) | 7’4” (2 jacks) | 6’2” (2 jacks) | 8’6” (1 jack) | 6’7” (2 jacks) | 5’6” (2 jacks) |
| 3 × 2×12 | 13’2” (1 jack) | 10’1” (2 jacks) | 8’6” (2 jacks) | 11’3” (2 jacks) | 8’8” (2 jacks) | 7’4” (2 jacks) | 10’0” (2 jacks) | 7’9” (2 jacks) | 6’6” (2 jacks) |
| 4 × 2×8 | 10’11” (1 jack) | 8’4” (1 jack) | 7’0” (1 jack) | 9’4” (1 jack) | 7’2” (1 jack) | 6’0” (1 jack) | 8’3” (1 jack) | 6’4” (1 jack) | 5’4” (2 jacks) |
| 4 × 2×10 | 12’11” (1 jack) | 9’11” (1 jack) | 8’4” (1 jack) | 11’1” (1 jack) | 8’6” (1 jack) | 7’2” (2 jacks) | 9’10” (1 jack) | 7’7” (2 jacks) | 6’4” (2 jacks) |
| 4 × 2×12 | 15’3” (1 jack) | 11’8” (1 jack) | 9’10” (2 jacks) | 13’0” (1 jack) | 10’0” (2 jacks) | 8’5” (2 jacks) | 11’7” (1 jack) | 8’11” (2 jacks) | 7’6” (2 jacks) |
2021 IRC Table R602.7(1) — exterior bearing wall header supporting roof and ceiling, No. 2 grade Douglas fir-larch, hem-fir, southern pine or spruce-pine-fir, ground snow load in psf by building width in feet. table source
Supporting roof, ceiling and one center-bearing floor
| Header | 30 psf ground snow | 50 psf ground snow | 70 psf ground snow | ||||||
|---|---|---|---|---|---|---|---|---|---|
| 12 ft wide | 24 ft wide | 36 ft wide | 12 ft wide | 24 ft wide | 36 ft wide | 12 ft wide | 24 ft wide | 36 ft wide | |
| 1 × 2×6 | 3’3” (1 jack) | 2’7” (2 jacks) | 2’2” (2 jacks) | 3’0” (2 jacks) | 2’4” (2 jacks) | 2’0” (2 jacks) | 2’9” (2 jacks) | 2’2” (2 jacks) | 1’10” (2 jacks) |
| 1 × 2×8 | 4’1” (2 jacks) | 3’3” (2 jacks) | 2’9” (2 jacks) | 3’9” (2 jacks) | 3’0” (2 jacks) | 2’6” (3 jacks) | 3’6” (2 jacks) | 2’9” (2 jacks) | 2’4” (3 jacks) |
| 1 × 2×10 | 4’11” (2 jacks) | 3’10” (2 jacks) | 3’3” (3 jacks) | 4’6” (2 jacks) | 3’6” (3 jacks) | 3’0” (3 jacks) | 4’1” (2 jacks) | 3’3” (3 jacks) | 2’9” (3 jacks) |
| 1 × 2×12 | 5’9” (2 jacks) | 4’6” (3 jacks) | 3’10” (3 jacks) | 5’3” (2 jacks) | 4’2” (3 jacks) | 3’6” (3 jacks) | 4’10” (3 jacks) | 3’10” (3 jacks) | 3’3” (4 jacks) |
| 2 × 2×4 | 3’3” (1 jack) | 2’6” (1 jack) | 2’2” (1 jack) | 3’0” (1 jack) | 2’4” (1 jack) | 2’0” (1 jack) | 2’8” (1 jack) | 2’2” (1 jack) | 1’10” (1 jack) |
| 2 × 2×6 | 4’10” (1 jack) | 3’9” (1 jack) | 3’3” (2 jacks) | 4’5” (1 jack) | 3’6” (2 jacks) | 3’0” (2 jacks) | 4’1” (1 jack) | 3’3” (2 jacks) | 2’9” (2 jacks) |
| 2 × 2×8 | 6’1” (1 jack) | 4’10” (2 jacks) | 4’1” (2 jacks) | 5’7” (2 jacks) | 4’5” (2 jacks) | 3’9” (2 jacks) | 5’2” (2 jacks) | 4’1” (2 jacks) | 3’6” (2 jacks) |
| 2 × 2×10 | 7’3” (2 jacks) | 5’8” (2 jacks) | 4’10” (2 jacks) | 6’8” (2 jacks) | 5’3” (2 jacks) | 4’5” (2 jacks) | 6’1” (2 jacks) | 4’10” (2 jacks) | 4’1” (2 jacks) |
| 2 × 2×12 | 8’6” (2 jacks) | 6’8” (2 jacks) | 5’8” (2 jacks) | 7’10” (2 jacks) | 6’2” (2 jacks) | 5’3” (3 jacks) | 7’2” (2 jacks) | 5’8” (2 jacks) | 4’10” (3 jacks) |
| 3 × 2×8 | 7’8” (1 jack) | 6’0” (1 jack) | 5’1” (2 jacks) | 7’0” (1 jack) | 5’6” (2 jacks) | 4’8” (2 jacks) | 6’5” (1 jack) | 5’1” (2 jacks) | 4’4” (2 jacks) |
| 3 × 2×10 | 9’1” (1 jack) | 7’2” (2 jacks) | 6’1” (2 jacks) | 8’4” (1 jack) | 6’7” (2 jacks) | 5’7” (2 jacks) | 7’8” (2 jacks) | 6’1” (2 jacks) | 5’2” (2 jacks) |
| 3 × 2×12 | 10’8” (2 jacks) | 8’5” (2 jacks) | 7’2” (2 jacks) | 9’10” (2 jacks) | 7’8” (2 jacks) | 6’7” (2 jacks) | 9’0” (2 jacks) | 7’1” (2 jacks) | 6’1” (2 jacks) |
| 4 × 2×8 | 8’10” (1 jack) | 6’11” (1 jack) | 5’11” (1 jack) | 8’1” (1 jack) | 6’4” (1 jack) | 5’5” (2 jacks) | 7’5” (1 jack) | 5’11” (1 jack) | 5’0” (2 jacks) |
| 4 × 2×10 | 10’6” (1 jack) | 8’3” (2 jacks) | 7’0” (2 jacks) | 9’8” (1 jack) | 7’7” (2 jacks) | 6’5” (2 jacks) | 8’10” (1 jack) | 7’0” (2 jacks) | 6’0” (2 jacks) |
| 4 × 2×12 | 12’4” (1 jack) | 9’8” (2 jacks) | 8’3” (2 jacks) | 11’4” (2 jacks) | 8’11” (2 jacks) | 7’7” (2 jacks) | 10’4” (2 jacks) | 8’3” (2 jacks) | 7’0” (2 jacks) |
2021 IRC Table R602.7(1) — exterior bearing wall header supporting roof, ceiling and one center-bearing floor, No. 2 grade Douglas fir-larch, hem-fir, southern pine or spruce-pine-fir, ground snow load in psf by building width in feet. table source
Supporting roof, ceiling and one clear-span floor
| Header | 30 psf ground snow | 50 psf ground snow | 70 psf ground snow | ||||||
|---|---|---|---|---|---|---|---|---|---|
| 12 ft wide | 24 ft wide | 36 ft wide | 12 ft wide | 24 ft wide | 36 ft wide | 12 ft wide | 24 ft wide | 36 ft wide | |
| 1 × 2×6 | 2’11” (2 jacks) | 2’3” (2 jacks) | 1’11” (2 jacks) | 2’9” (2 jacks) | 2’1” (2 jacks) | 1’9” (2 jacks) | 2’7” (2 jacks) | 2’0” (2 jacks) | 1’8” (2 jacks) |
| 1 × 2×8 | 3’9” (2 jacks) | 2’10” (2 jacks) | 2’5” (3 jacks) | 3’6” (2 jacks) | 2’8” (2 jacks) | 2’3” (3 jacks) | 3’3” (2 jacks) | 2’6” (3 jacks) | 2’2” (3 jacks) |
| 1 × 2×10 | 4’5” (2 jacks) | 3’5” (3 jacks) | 2’10” (3 jacks) | 4’2” (2 jacks) | 3’2” (3 jacks) | 2’8” (3 jacks) | 3’11” (2 jacks) | 3’0” (3 jacks) | 2’6” (3 jacks) |
| 1 × 2×12 | 5’2” (2 jacks) | 4’0” (3 jacks) | 3’4” (3 jacks) | 4’10” (3 jacks) | 3’9” (3 jacks) | 3’2” (4 jacks) | 4’7” (3 jacks) | 3’6” (3 jacks) | 3’0” (4 jacks) |
| 2 × 2×4 | 2’11” (1 jack) | 2’3” (1 jack) | 1’10” (1 jack) | 2’9” (1 jack) | 2’1” (1 jack) | 1’9” (1 jack) | 2’7” (1 jack) | 2’0” (1 jack) | 1’8” (1 jack) |
| 2 × 2×6 | 4’4” (1 jack) | 3’4” (2 jacks) | 2’10” (2 jacks) | 4’1” (1 jack) | 3’2” (2 jacks) | 2’8” (2 jacks) | 3’10” (1 jack) | 3’0” (2 jacks) | 2’6” (2 jacks) |
| 2 × 2×8 | 5’6” (2 jacks) | 4’3” (2 jacks) | 3’7” (2 jacks) | 5’2” (2 jacks) | 4’0” (2 jacks) | 3’4” (2 jacks) | 4’10” (2 jacks) | 3’9” (2 jacks) | 3’2” (2 jacks) |
| 2 × 2×10 | 6’7” (2 jacks) | 5’0” (2 jacks) | 4’2” (2 jacks) | 6’1” (2 jacks) | 4’9” (2 jacks) | 4’0” (2 jacks) | 5’9” (2 jacks) | 4’5” (2 jacks) | 3’9” (3 jacks) |
| 2 × 2×12 | 7’9” (2 jacks) | 5’11” (2 jacks) | 4’11” (3 jacks) | 7’2” (2 jacks) | 5’7” (2 jacks) | 4’8” (3 jacks) | 6’9” (2 jacks) | 5’3” (3 jacks) | 4’5” (3 jacks) |
| 3 × 2×8 | 6’11” (1 jack) | 5’3” (2 jacks) | 4’5” (2 jacks) | 6’5” (1 jack) | 5’0” (2 jacks) | 4’2” (2 jacks) | 6’1” (1 jack) | 4’8” (2 jacks) | 4’0” (2 jacks) |
| 3 × 2×10 | 8’3” (2 jacks) | 6’3” (2 jacks) | 5’3” (2 jacks) | 7’8” (2 jacks) | 5’11” (2 jacks) | 5’0” (2 jacks) | 7’3” (2 jacks) | 5’7” (2 jacks) | 4’8” (2 jacks) |
| 3 × 2×12 | 9’8” (2 jacks) | 7’5” (2 jacks) | 6’2” (2 jacks) | 9’0” (2 jacks) | 7’0” (2 jacks) | 5’10” (2 jacks) | 8’6” (2 jacks) | 6’7” (2 jacks) | 5’6” (3 jacks) |
| 4 × 2×8 | 8’0” (1 jack) | 6’1” (1 jack) | 5’1” (2 jacks) | 7’5” (1 jack) | 5’9” (2 jacks) | 4’10” (2 jacks) | 7’0” (1 jack) | 5’5” (2 jacks) | 4’7” (2 jacks) |
| 4 × 2×10 | 9’6” (1 jack) | 7’3” (2 jacks) | 6’1” (2 jacks) | 8’10” (1 jack) | 6’10” (2 jacks) | 5’9” (2 jacks) | 8’4” (1 jack) | 6’5” (2 jacks) | 5’5” (2 jacks) |
| 4 × 2×12 | 11’2” (2 jacks) | 8’6” (2 jacks) | 7’2” (2 jacks) | 10’5” (2 jacks) | 8’0” (2 jacks) | 6’9” (2 jacks) | 9’10” (2 jacks) | 7’7” (2 jacks) | 6’5” (2 jacks) |
2021 IRC Table R602.7(1) — exterior bearing wall header supporting roof, ceiling and one clear-span floor, No. 2 grade Douglas fir-larch, hem-fir, southern pine or spruce-pine-fir, ground snow load in psf by building width in feet. table source
Supporting roof, ceiling and two center-bearing floors
| Header | 30 psf ground snow | 50 psf ground snow | 70 psf ground snow | ||||||
|---|---|---|---|---|---|---|---|---|---|
| 12 ft wide | 24 ft wide | 36 ft wide | 12 ft wide | 24 ft wide | 36 ft wide | 12 ft wide | 24 ft wide | 36 ft wide | |
| 1 × 2×6 | 2’8” (2 jacks) | 2’1” (2 jacks) | 1’10” (2 jacks) | 2’7” (2 jacks) | 2’0” (2 jacks) | 1’9” (2 jacks) | 2’5” (2 jacks) | 1’11” (2 jacks) | 1’8” (2 jacks) |
| 1 × 2×8 | 3’5” (2 jacks) | 2’8” (2 jacks) | 2’4” (3 jacks) | 3’3” (2 jacks) | 2’7” (2 jacks) | 2’2” (3 jacks) | 3’1” (2 jacks) | 2’5” (3 jacks) | 2’1” (3 jacks) |
| 1 × 2×10 | 4’0” (2 jacks) | 3’2” (3 jacks) | 2’9” (3 jacks) | 3’10” (2 jacks) | 3’1” (3 jacks) | 2’7” (3 jacks) | 3’8” (2 jacks) | 2’11” (3 jacks) | 2’5” (3 jacks) |
| 1 × 2×12 | 4’9” (3 jacks) | 3’9” (3 jacks) | 3’2” (4 jacks) | 4’6” (3 jacks) | 3’7” (3 jacks) | 3’1” (4 jacks) | 4’3” (3 jacks) | 3’5” (3 jacks) | 2’11” (4 jacks) |
| 2 × 2×4 | 2’8” (1 jack) | 2’1” (1 jack) | 1’9” (1 jack) | 2’6” (1 jack) | 2’0” (1 jack) | 1’8” (1 jack) | 2’5” (1 jack) | 1’11” (1 jack) | 1’7” (1 jack) |
| 2 × 2×6 | 4’0” (1 jack) | 3’2” (2 jacks) | 2’8” (2 jacks) | 3’9” (1 jack) | 3’0” (2 jacks) | 2’7” (2 jacks) | 3’7” (1 jack) | 2’10” (2 jacks) | 2’5” (2 jacks) |
| 2 × 2×8 | 5’0” (2 jacks) | 4’0” (2 jacks) | 3’5” (2 jacks) | 4’10” (2 jacks) | 3’10” (2 jacks) | 3’3” (2 jacks) | 4’7” (2 jacks) | 3’7” (2 jacks) | 3’1” (2 jacks) |
| 2 × 2×10 | 6’0” (2 jacks) | 4’9” (2 jacks) | 4’0” (2 jacks) | 5’8” (2 jacks) | 4’6” (2 jacks) | 3’10” (3 jacks) | 5’5” (2 jacks) | 4’3” (2 jacks) | 3’8” (3 jacks) |
| 2 × 2×12 | 7’0” (2 jacks) | 5’7” (2 jacks) | 4’9” (3 jacks) | 6’8” (2 jacks) | 5’4” (3 jacks) | 4’6” (3 jacks) | 6’4” (2 jacks) | 5’0” (3 jacks) | 4’3” (3 jacks) |
| 3 × 2×8 | 6’4” (1 jack) | 5’0” (2 jacks) | 4’3” (2 jacks) | 6’0” (1 jack) | 4’9” (2 jacks) | 4’1” (2 jacks) | 5’8” (2 jacks) | 4’6” (2 jacks) | 3’10” (2 jacks) |
| 3 × 2×10 | 7’6” (2 jacks) | 5’11” (2 jacks) | 5’1” (2 jacks) | 7’1” (2 jacks) | 5’8” (2 jacks) | 4’10” (2 jacks) | 6’9” (2 jacks) | 5’4” (2 jacks) | 4’7” (2 jacks) |
| 3 × 2×12 | 8’10” (2 jacks) | 7’0” (2 jacks) | 5’11” (2 jacks) | 8’5” (2 jacks) | 6’8” (2 jacks) | 5’8” (3 jacks) | 8’0” (2 jacks) | 6’4” (2 jacks) | 5’4” (3 jacks) |
| 4 × 2×8 | 7’3” (1 jack) | 5’9” (1 jack) | 4’11” (2 jacks) | 6’11” (1 jack) | 5’6” (2 jacks) | 4’8” (2 jacks) | 6’7” (1 jack) | 5’2” (2 jacks) | 4’5” (2 jacks) |
| 4 × 2×10 | 8’8” (1 jack) | 6’10” (2 jacks) | 5’10” (2 jacks) | 8’3” (2 jacks) | 6’6” (2 jacks) | 5’7” (2 jacks) | 7’10” (2 jacks) | 6’2” (2 jacks) | 5’3” (2 jacks) |
| 4 × 2×12 | 10’2” (2 jacks) | 8’1” (2 jacks) | 6’10” (2 jacks) | 9’8” (2 jacks) | 7’8” (2 jacks) | 6’7” (2 jacks) | 9’2” (2 jacks) | 7’3” (2 jacks) | 6’2” (2 jacks) |
2021 IRC Table R602.7(1) — exterior bearing wall header supporting roof, ceiling and two center-bearing floors, No. 2 grade Douglas fir-larch, hem-fir, southern pine or spruce-pine-fir, ground snow load in psf by building width in feet. table source
Supporting roof, ceiling and two clear-span floors
| Header | 30 psf ground snow | 50 psf ground snow | 70 psf ground snow | ||||||
|---|---|---|---|---|---|---|---|---|---|
| 12 ft wide | 24 ft wide | 36 ft wide | 12 ft wide | 24 ft wide | 36 ft wide | 12 ft wide | 24 ft wide | 36 ft wide | |
| 1 × 2×6 | 2’3” (2 jacks) | 1’9” (2 jacks) | 1’5” (2 jacks) | 2’3” (2 jacks) | 1’9” (2 jacks) | 1’5” (3 jacks) | 2’2” (2 jacks) | 1’8” (2 jacks) | 1’5” (3 jacks) |
| 1 × 2×8 | 2’10” (2 jacks) | 2’2” (3 jacks) | 1’10” (3 jacks) | 2’10” (2 jacks) | 2’2” (3 jacks) | 1’10” (3 jacks) | 2’9” (2 jacks) | 2’1” (3 jacks) | 1’10” (3 jacks) |
| 1 × 2×10 | 3’4” (2 jacks) | 2’7” (3 jacks) | 2’2” (3 jacks) | 3’4” (3 jacks) | 2’7” (3 jacks) | 2’2” (4 jacks) | 3’3” (3 jacks) | 2’6” (3 jacks) | 2’2” (4 jacks) |
| 1 × 2×12 | 4’0” (3 jacks) | 3’0” (3 jacks) | 2’7” (4 jacks) | 4’0” (3 jacks) | 3’0” (4 jacks) | 2’7” (4 jacks) | 3’10” (3 jacks) | 3’0” (4 jacks) | 2’6” (4 jacks) |
| 2 × 2×4 | 2’3” (1 jack) | 1’8” (1 jack) | 1’4” (1 jack) | 2’3” (1 jack) | 1’8” (1 jack) | 1’4” (1 jack) | 2’2” (1 jack) | 1’8” (1 jack) | 1’4” (2 jacks) |
| 2 × 2×6 | 3’4” (1 jack) | 2’6” (2 jacks) | 2’2” (2 jacks) | 3’4” (2 jacks) | 2’6” (2 jacks) | 2’2” (2 jacks) | 3’3” (2 jacks) | 2’6” (2 jacks) | 2’1” (2 jacks) |
| 2 × 2×8 | 4’3” (2 jacks) | 3’3” (2 jacks) | 2’8” (2 jacks) | 4’3” (2 jacks) | 3’3” (2 jacks) | 2’8” (2 jacks) | 4’1” (2 jacks) | 3’2” (2 jacks) | 2’8” (3 jacks) |
| 2 × 2×10 | 5’0” (2 jacks) | 3’10” (2 jacks) | 3’2” (3 jacks) | 5’0” (2 jacks) | 3’10” (2 jacks) | 3’2” (3 jacks) | 4’10” (2 jacks) | 3’9” (3 jacks) | 3’2” (3 jacks) |
| 2 × 2×12 | 5’11” (2 jacks) | 4’6” (3 jacks) | 3’9” (3 jacks) | 5’11” (2 jacks) | 4’6” (3 jacks) | 3’9” (3 jacks) | 5’8” (2 jacks) | 4’5” (3 jacks) | 3’9” (3 jacks) |
| 3 × 2×8 | 5’3” (1 jack) | 4’0” (2 jacks) | 3’5” (2 jacks) | 5’3” (2 jacks) | 4’0” (2 jacks) | 3’5” (2 jacks) | 5’1” (2 jacks) | 3’11” (2 jacks) | 3’4” (2 jacks) |
| 3 × 2×10 | 6’3” (2 jacks) | 4’9” (2 jacks) | 4’0” (2 jacks) | 6’3” (2 jacks) | 4’9” (2 jacks) | 4’0” (2 jacks) | 6’1” (2 jacks) | 4’8” (2 jacks) | 4’0” (3 jacks) |
| 3 × 2×12 | 7’5” (2 jacks) | 5’8” (2 jacks) | 4’9” (3 jacks) | 7’5” (2 jacks) | 5’8” (2 jacks) | 4’9” (3 jacks) | 7’2” (2 jacks) | 5’6” (3 jacks) | 4’8” (3 jacks) |
| 4 × 2×8 | 6’1” (1 jack) | 4’8” (2 jacks) | 3’11” (2 jacks) | 6’1” (1 jack) | 4’8” (2 jacks) | 3’11” (2 jacks) | 5’11” (1 jack) | 4’7” (2 jacks) | 3’10” (2 jacks) |
| 4 × 2×10 | 7’3” (2 jacks) | 5’6” (2 jacks) | 4’8” (2 jacks) | 7’3” (2 jacks) | 5’6” (2 jacks) | 4’8” (2 jacks) | 7’0” (2 jacks) | 5’5” (2 jacks) | 4’7” (2 jacks) |
| 4 × 2×12 | 8’6” (2 jacks) | 6’6” (2 jacks) | 5’6” (2 jacks) | 8’6” (2 jacks) | 6’6” (2 jacks) | 5’6” (2 jacks) | 8’3” (2 jacks) | 6’4” (2 jacks) | 5’4” (3 jacks) |
2021 IRC Table R602.7(1) — exterior bearing wall header supporting roof, ceiling and two clear-span floors, No. 2 grade Douglas fir-larch, hem-fir, southern pine or spruce-pine-fir, ground snow load in psf by building width in feet. table source
Interior bearing walls
2021 IRC Table R602.7(2). Rows are the header size under each supporting condition; columns are the building width in feet.
| Header | Building width (feet) | ||
|---|---|---|---|
| 12 ft | 24 ft | 36 ft | |
| Supporting one floor only | |||
| 2 × 2×4 | 4’1” (1 jack) | 2’10” (1 jack) | 2’4” (1 jack) |
| 2 × 2×6 | 6’1” (1 jack) | 4’4” (1 jack) | 3’6” (1 jack) |
| 2 × 2×8 | 7’9” (1 jack) | 5’5” (1 jack) | 4’5” (2 jacks) |
| 2 × 2×10 | 9’2” (1 jack) | 6’6” (2 jacks) | 5’3” (2 jacks) |
| 2 × 2×12 | 10’9” (1 jack) | 7’7” (2 jacks) | 6’3” (2 jacks) |
| 3 × 2×8 | 9’8” (1 jack) | 6’10” (1 jack) | 5’7” (1 jack) |
| 3 × 2×10 | 11’5” (1 jack) | 8’1” (1 jack) | 6’7” (2 jacks) |
| 3 × 2×12 | 13’6” (1 jack) | 9’6” (2 jacks) | 7’9” (2 jacks) |
| 4 × 2×8 | 11’2” (1 jack) | 7’11” (1 jack) | 6’5” (1 jack) |
| 4 × 2×10 | 13’3” (1 jack) | 9’4” (1 jack) | 7’8” (1 jack) |
| 4 × 2×12 | 15’7” (1 jack) | 11’0” (1 jack) | 9’0” (2 jacks) |
| Supporting two floors | |||
| 2 × 2×4 | 2’7” (1 jack) | 1’11” (1 jack) | 1’7” (1 jack) |
| 2 × 2×6 | 3’11” (1 jack) | 2’11” (2 jacks) | 2’5” (2 jacks) |
| 2 × 2×8 | 5’0” (1 jack) | 3’8” (2 jacks) | 3’1” (2 jacks) |
| 2 × 2×10 | 5’11” (2 jacks) | 4’4” (2 jacks) | 3’7” (2 jacks) |
| 2 × 2×12 | 6’11” (2 jacks) | 5’2” (2 jacks) | 4’3” (3 jacks) |
| 3 × 2×8 | 6’3” (1 jack) | 4’7” (2 jacks) | 3’10” (2 jacks) |
| 3 × 2×10 | 7’5” (1 jack) | 5’6” (2 jacks) | 4’6” (2 jacks) |
| 3 × 2×12 | 8’8” (2 jacks) | 6’5” (2 jacks) | 5’4” (2 jacks) |
| 4 × 2×8 | 7’2” (1 jack) | 5’4” (1 jack) | 4’5” (2 jacks) |
| 4 × 2×10 | 8’6” (1 jack) | 6’4” (2 jacks) | 5’3” (2 jacks) |
| 4 × 2×12 | 10’1” (1 jack) | 7’5” (2 jacks) | 6’2” (2 jacks) |
2021 IRC Table R602.7(2) — interior bearing wall header, No. 2 grade Douglas fir-larch, hem-fir, southern pine or spruce-pine-fir, by building width in feet. table source
Common questions
What does NJ mean in the header table?
NJ is the number of jack studs the table requires at each end of the header — the studs under the header ends that carry it down to the plate. It is printed in this page as “(2 jacks)” next to the span, and it changes with the size, the load the header supports, the ground snow load, and the building width.
What does 2-2x10 mean in the header table?
It is the number of plies followed by the lumber size. A 2-2×10 header is two 2×10s fastened together; a 3-2×12 is three 2×12s fastened together. Each ply count is its own row, so read the row that matches the header you have.
My ground snow load is under 30 psf — which column applies?
The table’s own instruction is that where the ground snow load is less than 30 psf and the roof live load is 20 psf or less, the 30 psf ground snow columns apply. Confirm the ground snow load for your address with your building department.