2308.4.2.1 Span.
BC § 2308.4.2.1
Spans for floor joists shall be in accordance with Table 2308.4.2.1(1) or 2308.4.2.1(2) or the AWC STJR. Table 2308.4.2.1(1)Floor Joist Spans for Common Lumber Species(Residential sleeping areas, live load = 30 psf, L/Δ = 360) Joist Spacing (inches)Species and Grade Dead Load = 10 psfDead Load = 20 psf2 × 62 × 82 × 102 × 122 × 62 × 82 × 102 × 12Maximum floor joist spans(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)Joist Spacing (inches)Species and Grade Dead Load = 10 psfDead Load = 20 psf2 × 62 × 82 × 102 × 122 × 62 × 82 × 102 × 12Maximum floor joist spans(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)12Douglas Fir-LarchSS 12-6 16-6 21-0 25-7 12-6 16-6 21-025-7Douglas Fir-Larch#1 12-0 15-10 20-3 24-8 12-0 15-7 19-022-0Douglas Fir-Larch#2 11-10 15-7 19-10 23-0 11-614-7 17-920-7Douglas Fir-Larch#3 9-8 12-4 15-017-5 8-811-0 13-515-7Hem-FirSS 11-1015-7 19-10 24-2 11-10 15-7 19-1024-2Hem-Fir#1 11-7 15-3 19-5 23-7 11-7 15-2 18-6 21-6Hem-Fir#2 11-0 14-6 18-6 22-6 11-014-4 17-620-4Hem-Fir#3 9-8 12-4 15-0 17-5 8-8 11-0 13-5 15-7Southern Pine SS 12-316-220-825-112-316-220-825-1Southern Pine #1 11-1015-7 19-1024-2 11-1015-7 18-722-0Southern Pine #2 11-314-11 18-1 21-4 10-913-816-219-1Southern Pine #3 9-2 11-6 14-0 16-6 8-210-3 12-6 14-9Spruce-Pine-FirSS 11-7 15-3 19-5 23-7 11-7 15-3 19-5 23-7Spruce-Pine-Fir#1 11-3 14-11 19-0 23-0 11-3 14-7 17-920-7Spruce-Pine-Fir#2 11-314-11 19-0 23-0 11-314-7 17-9 20-7Spruce-Pine-Fir#3 9-8 12-4 15-0 17-5 8-8 11-0 13-515-7 16Douglas Fir-LarchSS 11-4 15-0 19-1 23-3 11-4 15-0 19-1 23-0Douglas Fir-Larch#1 10-11 14-5 18-5 21-410-813-6 16-5 19-1Douglas Fir-Larch#2 10-914-1 17-2 19-11 9-1112-715-5 17-10Douglas Fir-Larch#3 8-5 10-8 13-0 15-17-6 9-6 11-8 13-6Hem-Fir SS 10-9 14-2 18-0 21-11 10-9 14-2 18-0 21-11Hem-Fir #1 10-6 13-10 17-820-9 10-413-1 16-0 18-7Hem-Fir #2 10-013-2 16-10 19-8 9-1012-515-2 17-7Hem-Fir #3 8-5 10-8 13-0 15-1 7-6 9-6 11-8 13-6 Southern Pine SS 11-214-818-922-1011-214-818-922-10Southern Pine #1 10-9 14-2 18-0 21-410-9 13-916-119-1Southern Pine #2 10-313-315-818-69-411-1014-016-6Southern Pine #3 7-1110-1012-114-47-1 8-1110-1012-10Spruce-Pine-FirSS 10-6 13-10 17-8 21-610-613-10 17-8 21-4Spruce-Pine-Fir#1 10-3 13-6 17-2 19-119-1112-7 15-5 17-10Spruce-Pine-Fir#2 10-313-6 17-2 19-11 9-1112-715-5 17-10Spruce-Pine-Fir#3 8-5 10-8 13-0 15-1 7-6 9-6 11-813-6 19.2Douglas Fir-LarchSS10-8 14-1 18-0 21-10 10-814-1 18-0 21-0Douglas Fir-Larch#110-413-7 16-9 19-6 9-812-4 15-0 17-5Douglas Fir-Larch#210-112-1015-818-3 9-111-614-1 16-3Douglas Fir-Larch#37-89-9 11-10 13-9 6-10 8-8 10-7 12-4Hem-FirSS10-113-4 17-0 20-8 10-113-4 17-0 20-7Hem-Fir#19-1013-0 16-4 19-0 9-612-0 14-817-0Hem-Fir#29-512-515-617-1 8-1111-413-10 16-1Hem-Fir#37-8 9-9 11-10 13-9 6-10 8-8 10-7 12-4 Southern PineSS10-613-1017-821-610-613-1017-821-6Southern Pine#110-113-4 16-519-69-1112-7 14-817-5Southern Pine#29-612-114-416-108-610-1012-1015-1Southern Pine#37-39-111-013-16-58-29-1011-8Spruce-Pine-FirSS9-1013-0 16-7 20-2 9-1013-0 16-7 19-6Spruce-Pine-Fir#19-812-915-8 18-3 9-111-6 14-1 16-3Spruce-Pine-Fir#29-812-915-818-3 9-111-614-1 16-3Spruce-Pine-Fir#37-8 9-9 11-10 13-9 6-10 8-8 10-712-4 24Douglas Fir-LarchSS9-1113-116-820-39-1113-116-2 18-9Douglas Fir-Larch#19-712-415-017-58-811-013-5 15-7Douglas Fir-Larch#2 9-111-614-116-38-110-312-714-7Douglas Fir-Larch#3 6-108-810-712-46-27-99-6 11-0Hem-FirSS 9-412-415-919-29-412-415-9 18-5Hem-Fir#1 9-212-014-817-08-610-913-1 15-2Hem-Fir#2 8-911-413-1016-18-010-212-514-4Hem-Fir#3 6-10 8-8 10-7 12-4 6-2 7-9 9-6 11-0 Southern PineSS 9-912-1016-519-119-912-1016-519-8Southern Pine#1 9-412-414-817-58-1011-313-115-7Southern Pine#2 8-610-1012-1015-17-79-811-513-6Southern Pine#3 6-58-29-1011-85-97-38-1010-5Spruce-Pine-FirSS 9-212-115-518-99-212-115-0 17-5Spruce-Pine-Fir#1 8-1111-614-116-38-110-312-7 14-7Spruce-Pine-Fir#2 8-1111-614-116-38-110-312-714-7Spruce-Pine-Fir#3 6-108-810-712-46-2 7-9 9-611-0 For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square foot = 0.0479 kPa. Note: Check sources for availability of lumber in lengths greater than 20 feet. Table 2308.4.2.1(2)Floor Joist Spans for Common Lumber Species(Residential living areas, live load = 40 psf, L/Δ = 360) Joist Spacing (inches)Species and Grade Dead Load = 10 psfDead Load = 20 psf2 × 62 × 82 × 102 × 122 × 62 × 82 × 102 × 12Maximum floor joist spans(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)Joist Spacing (inches)Species and Grade Dead Load = 10 psfDead Load = 20 psf2 × 62 × 82 × 102 × 122 × 62 × 82 × 102 × 12Maximum floor joist spans(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)12Douglas Fir-LarchSS 11-415-019-123-3 11-4 15-0 19-123-3 Douglas Fir-Larch#1 10-1114-518-522-0 10-11 14-2 17-420-1 Douglas Fir-Larch#2 10-914-217-920-7 10-613-3 16-318-10 Douglas Fir-Larch#3 8-811-013-515-7 7-11 10-0 12-314-3 Hem-Fir SS 10-914-218-021-11 10-9 14-2 18-021-11 Hem-Fir#1 10-613-1017-821-6 10-6 13-10 16-1119-7 Hem-Fir#2 10-013-216-1020-4 10-013-1 16-018-6 Hem-Fir#3 8-8 11-0 13-5 15-7 7-11 10-0 12-3 14-3 Southern Pine SS 11-214-818-922-1011-214-818-922-10Southern Pine #1 10-914-218-021-1110-9 14-2 16-1120-1Southern Pine #2 10-313-616-219-19-1012-614-917-5Southern Pine #3 8-210-312-614-97-59-511-513-6Spruce-Pine-FirSS 10-613-1017-821-6 10-6 13-10 17-821-6 Spruce-Pine-Fir#1 10-313-617-320-7 10-3 13-3 16-318-10 Spruce-Pine-Fir#2 10-313-617-320-7 10-313-316-318-10Spruce-Pine-Fir#3 8-811-013-5 15-7 7-11 10-012-3 14-3 16Douglas Fir-LarchSS 10-413-7 17-421-1 10-413-7 17-421-0Douglas Fir-Larch#1 9-1113-1 16-519-1 9-812-4 15-017-5Douglas Fir-Larch#2 9-912-715-517-10 9-111-614-116-3Douglas Fir-Larch#3 7-69-6 11-813-6 6-108-8 10-712-4Hem-FirSS 9-912-10 16-519-11 9-912-10 16-519-11Hem-Fir#1 9-612-7 16-018-7 9-612-0 14-817-0Hem-Fir#2 9-112-015-217-7 8-1111-413-1016-1Hem-Fir#3 7-6 9-6 11-8 13-6 6-10 8-8 10-7 12-4 Southern Pine SS 10-213-417-020-910-213-417-020-9Southern Pine #1 9-912-1016-119-19-912-714-817-5Southern Pine #2 9-411-10 14-016-68-610-1012-1015-1Southern Pine #3 7-18-1110-1012-106-58-29-1011-8Spruce-Pine-FirSS 9-612-7 16-019-6 9-612-7 16-019-6Spruce-Pine-Fir#1 9-412-3 15-517-10 9-111-6 14-116-3Spruce-Pine-Fir#2 9-412-315-517-109-111-614-116-3Spruce-Pine-Fir#3 7-6 9-611-8 13-66-10 8-810-712-4 19.2Douglas Fir-LarchSS 9-812-10 16-4 19-10 9-812-1016-419-2 Douglas Fir-Larch#1 9-412-4 15-0 17-5 8-1011-313-815-11 Douglas Fir-Larch#2 9-111-614-1 16-3 8-310-612-1014-10 Douglas Fir-Larch#3 6-108-8 10-7 12-4 6-37-119-811-3 Hem-FirSS 9-212-1 15-5 18-9 9-212-115-518-9 Hem-Fir#1 9-011-10 14-8 17-08-810-1113-415-6 Hem-Fir#2 8-711-313-10 16-1 8-210-412-814-8 Hem-Fir#3 6-10 8-8 10-7 12-4 6-3 7-11 9-8 11-3 Southern Pine SS 9-612-716-019-69-612-716-019-6Southern Pine #1 9-212-1 14-817-5 9-011-513-515-11Southern Pine #2 8-610-1012-1015-17-99-1011-813-9Southern Pine #3 6-58-29-1011-85-117-59-010-8Spruce-Pine-FirSS 9-011-10 15-1 18-4 9-011-1015-117-9 Spruce-Pine-Fir#18-911-6 14-1 16-3 8-310-612-1014-10 Spruce-Pine-Fir#2 8-911-614-116-38-310-612-1014-10Spruce-Pine-Fir#3 6-10 8-8 10-7 12-46-37-119-8 11-3 24Douglas Fir-Larch SS 9-011-1115-218-5 9-011-11 14-9 17-1 Douglas Fir-Larch #1 8-811-013-515-7 7-1110-012-3 14-3 Douglas Fir-Larch #2 8-110-312-714-7 7-59-511-613-4 Douglas Fir-Larch #3 6-27-99-611-0 5-77-1 8-8 10-1 Hem-FirSS 8-611-314-417-5 8-611-314-4 16-10a Hem-Fir#1 8-410-913-115-2 7-99-911-11 13-10 Hem-Fir#2 7-1110-212-514-4 7-49-311-413-1 Hem-Fir#3 6-2 7-9 9-6 11-0 5-7 7-1 8-8 10-1 Southern Pine SS 8-1011-814-1118-18-1011-814-1118-0Southern Pine #1 8-611-313-115-78-110-3 12-014-3Southern Pine #2 7-79-811-513-67-08-1010-512-4Southern Pine #3 5-97-38-1010-55-36-8 8-1 9-6Spruce-Pine-FirSS 8-411-014-017-0 8-411-013-8 15-11 Spruce-Pine-Fir#1 8-110-312-714-7 7-59-511-6 13-4 Spruce-Pine-Fir#2 8-110-312-714-77-59-511-613-4 Spruce-Pine-Fir#3 6-27-99-6 11-05-7 7-1 8-8 10-1 For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square foot = 0.0479 kPa. Note: Check sources for availability of lumber in lengths greater than 20 feet. a. End bearing length shall be increased to 2 inches.
