2308.7.2 Rafter spans.
BC § 2308.7.2
Spans for rafters shall be in accordance with Table 2308.7.2(1), 2308.7.2(2), 2308.7.2(3), 2308.7.2(4), 2308.7.2(5), or 2308.7.2(6). For other grades and species and other loading conditions, refer to the AWC STJR. The span of each rafter shall be measured along the horizontal projection of the rafter. Table 2308.7.2(1)Rafter Spans for Common Lumber Species(Roof Live Load = 20 psf, Ceiling Not Attached to Rafters, L/Δ = 180) Rafter Spacing (inches)Species and GradeDead Load = 10 psfDead Load = 20 psf2 × 42 × 62 × 82 × 102 × 122 × 42 × 62 × 82 × 102 × 12Maximum rafter spans a(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)Rafter Spacing (inches)Species and GradeDead Load = 10 psfDead Load = 20 psf2 × 42 × 62 × 82 × 102 × 122 × 42 × 62 × 82 × 102 × 12Maximum rafter spans a(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)12Douglas Fir-Larch SS11-618-023-9Note bNote b11-618-018-0Note bNote bDouglas Fir-Larch #111-117-422-5Note bNote b10-615-415-423-9Note bDouglas Fir-Larch #210-1016-721-025-8Note b9-1014-418-222-325-9Douglas Fir-Larch #38-712-615-1019-522-67-510-1013-916-919-6Hem-Fir SS10-1017-022-5Note bNote b10-1017-022-5Note bNote bHem-Fir #110-716-821-10Note bNote b10-314-1118-1123-2Note bHem-Fir #210-115-1120-825-3Note b9-814-217-1121-1125-5Hem-Fir #38-712-615-1019-522-67-510-1013-916-919-6Southern Pine SS11-317-823-4Note bNote b11-317-823-4Note bNote bSouthern Pine #1 10-1017-022-526-026-010-615-819-1023-2Note bSouthern Pine #210-415-719-823-526-09-013-617-1 20-323-10Southern Pine #38-011-914-1018-021-46-1110-212-10 15-718-6Spruce-Pine-Fir SS10-716-821-11Note bNote b10-716-821-9Note bNote bSpruce-Pine-Fir #110-416-321-025-8Note b9-1014-418-222-325-9Spruce-Pine-Fir #210-416-321-025-8Note b9-1014-418-222-325-9Spruce-Pine-Fir #38-712-615-1019-522-67-510-1013-916-919-616Douglas Fir-Larch SS10-516-421-7Note bNote b10-516-020-324-9Note bDouglas Fir-Larch #110-015-419-523-9Note b9-113-316-1020-723-10Douglas Fir-Larch #29-1014-418-222-325-98-612-515-919-322-4Douglas Fir-Larch #37-510-1013-916-919-66-59-511-1114-616-10Hem-Fir SS9-1015-620-5Note bNote b9-1015-619-1124-4Note bHem-Fir #19-814-1118-1123-2Note b8-1012-1116-520-023-3Hem-Fir #29-214-217-1121-1125-58-512-315-618-1122-0Hem-Fir #37-510-1013-916-919-66-59-511-1114-616-10Southern Pine SS10-316-121-2Note bNote b10-316-121-225-7Note bSouthern Pine #19-1015-619-1023-226-09-113-717-2 20-123-10Southern Pine #29-013-617-120-323-107-911-814-9 17-620-8Southern Pine #36-1110-212-1015-718-66-08-1011-2 13-616-0Spruce-Pine-Fir SS9-815-219-1125-5Note a9-814-1018-1023-0Note aSpruce-Pine-Fir #19-514-418-222-325-98-612-515-919-322-4Spruce-Pine-Fir #29-514-418-222-325-98-612-515-919-322-4Spruce-Pine-Fir #37-510-1013-916-919-66-59-511-1114-616-1019.2Douglas Fir-Larch SS9-1015-520-425-11Note b9-1014-718-622-7Note bDouglas Fir-Larch #19-514-017-921-825-28-412-215-418-921-9Douglas Fir-Larch #28-1113-116720-323-67-911-414-417-720-4Douglas Fir-Larch #36-99-1112-715-417-95-108-710-1013-315-5Hem-Fir SS9-314-719-224-6Note b9-314-418-222-325-9Hem-Fir #19-113-817-421-124-68-111-1015-018-421-3Hem-Fir #28-812-1116-420-023-27-811-214-217-420-1Hem-Fir #36-99-1112-715-417-95-108-710-1013-315-5Southern Pine SS9-815-219-1125-5Note b9-815-219-1125-5Note bSouthern Pine #19-314-318-121-225-28-412-415-8 18-421-9Southern Pine #28-212-315-718-621-97-110-813-6 16-018-10Southern Pine #36-49-411-914-316-105-68-110-212-414-7Spruce-Pine-Fir SS9-114-318-923-11Note b9-113-717-221-024-4Spruce-Pine-Fir #18-1013-116-720-323-67-911-414-417-720-4Spruce-Pine-Fir #28-1013-116-720-323-67-911-414-417-720-4Spruce-Pine-Fir #36-99-1112-715-417-95-108-710-1013-315-524Douglas Fir-Larch SS9-114-418-1023-4Note b8-1113-116-720-323-5Douglas Fir-Larch #18-712-615-1019-522-67-510-1013-916-919-6Douglas Fir-Larch #28-011-914-1018-221-06-1110-212-1015-818-3Douglas Fir-Larch #36-18-1011-313-815-115-37-89-911-1013-9Hem-Fir SS8-713-617-1022-9Note b8-712-1016-319-1023-0Hem-Fir #18-412-315-618-1121-117-310-713-516-419-0Hem-Fir #27-1111-714-817-1020-96-1010-012-815-617-11Hem-Fir #36-18-1011-313-815-115-37-89-911-1013-9Southern Pine SS8-1114-118-623-8Note b8-1114-118-622-11Note bSouthern Pine #18-712-916-218-1122-67-511-114-0 16-519-6Southern Pine #27-411-013-1116-619-66-49-612-1 14-416-10Southern Pine #35-88-410-612-915-14-117-39-1 11-013-1Spruce-Pine-Fir SS8-513-317-521-825-28-412-215-418-921-9Spruce-Pine-Fir #18-011-914-1018-221-06-1110-212-1015-818-3Spruce-Pine-Fir #28-011-914-1018-221-06-1110-212-1015-818-3Spruce-Pine-Fir #36-18-1011-313815-115-37-89-911-1013-9 Check sources for availability of lumber in lengths greater than 20 feet. For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square foot = 0.0479 kPa. a. The tabulated rafter spans assume that ceiling joists are located at the bottom of the attic space or that some other method of resisting the outward push of the rafters on the bearing walls, such as rafter ties, is provided at that location. Where ceiling joists or rafter ties are located higher in the attic space, the rafter spans shall be multiplied by the following factors: Hc/HRRafter Span Adjustment Factor1/30.671/40.761/50.831/60.901/7.5 or less1.00 where: Hc = Height of ceiling joists or rafter ties measured vertically above the top of the rafter support walls. HR = Height of roof ridge measured vertically above the top of the rafter support walls. b. Span exceeds 26 feet in length. Table 2308.7.2(2)Rafter Spans for Common Lumber Species(Roof Live Load = 20 psf, Ceiling Attached to Rafters, L/Δ = 240) Rafter Spacing (inches)Species and GradeDead Load = 10 psfDead Load = 20 psf2 × 42 × 62 × 82 × 102 × 122 × 42 × 62 × 82 × 102 × 12Maximum rafter spans a(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)Rafter Spacing (inches)Species and GradeDead Load = 10 psfDead Load = 20 psf2 × 42 × 62 × 82 × 102 × 122 × 42 × 62 × 82 × 102 × 12Maximum rafter spans a(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)12Douglas Fir-Larch SS10-516-421-7Note bNote b10-516-421-7Note bNote bDouglas Fir-Larch #110-015-920-10Note bNote b10-015-419-523-9Note bDouglas Fir-Larch #29-1015-620-525-8Note b9-1014-418-222-325-9Douglas Fir-Larch #38-712-615-1019-522-67-510-1013-916-919-6Hem-Fir SS9-1015-620-5Note bNote b9-1015-620-5Note bNote bHem-Fir #19-815-219-1125-5Note b9-814-1118-1123-2Note bHem-Fir #29-214-519-024-3Note b9-214-217-1121-1125-5Hem-Fir #38-712-615-1019-522-67-510-1013-916-919-6Southern Pine SS10-316-121-2Note bNote b10-316-121-2Note bNote bSouthern Pine #19-1015-620-526-026-09-1015-619-1023-226-0Southern Pine #29-514-919-623-526-09-013-617-1 20-323-10Southern Pine #38-011-914-1018-021-46-1110-212-10 15-718-6Spruce-Pine-Fir SS9-815-219-1125-5Note b9-815-219-1125-5Note bSpruce-Pine-Fir #19-514-919-624-10Note b9-514-418-222-325-9Spruce-Pine-Fir #29-514-919-624-10Note b9-514-418-222-325-9Spruce-Pine-Fir #38-712-615-1019-522-67-510-1013-916-919-616Douglas Fir-Larch SS9-614-1119-725-0Note b9-614-1119-724-9Note bDouglas Fir-Larch #19-114-418-1123-9Note b9-113-316-1020-723-10Douglas Fir-Larch #28-1114-118-222-325-98-612-515-919-322-4Douglas Fir-Larch #37-510-1013-916-919-66-59-511-1114-616-10Hem-Fir SS8-1114-118-623-8Note b8-1114-118-623-8Note bHem-Fir #18-913-918-123-1Note b8-912-1116-520-023-3Hem-Fir #28-413-117-321-1125-58-412-315-618-1122-0Hem-Fir #37-510-1013-916-919-66-59-511-1114-616-10Southern Pine SS9-414-719-324-7Note b9-414-719-324-7Note bSouthern Pine #18-1114-118-623-226-08-1113-717-2 20-123-10Southern Pine #28-713-517-120-323-107-911-814-9 17-620-8Southern Pine #36-1110-212-1015-718-66-08-1011-2 13-616-0Spruce-Pine-Fir SS8-913-918-123-1Note b8-913-918-123-0Note bSpruce-Pine-Fir #18-713-517-922-325-98-612-515-919-322-4Spruce-Pine-Fir #28-713-517-922-325-98-612-515-919-322-4Spruce-Pine-Fir #37-510-1013-916-919-66-59-511-1114-616-1019.2Douglas Fir-Larch SS8-1114-018-523-7Note b8-1114-018-522-7Note bDouglas Fir-Larch #18-713-617-921-825-28-412-215-418-921-9Douglas Fir-Larch #28-513-116-720-323-67-911-414-417-320-4Douglas Fir-Larch #36-99-1112-715-417-95-108-710-1013-315-5Hem-Fir SS8-513-317-522-3Note b8-513-317-522-325-9Hem-Fir #18-312-1117-121-124-68-111-1015-018-421-3Hem-Fir #27-1012-416-320-023-27-811-214-217-420-1Hem-Fir #36-99-1112-715-417-95-108-710-1013-315-5Southern Pine SS8-913-918-123-1Note b8-913-918-123-1Note bSouthern Pine #18-513-317-521-225-28-412-415-8 18-421-9Southern Pine #28-112-315-718-621-97-110-813-6 16-018-10Southern Pine #36-49-411-914-316-105-68-110-212-414-7Spruce-Pine-Fir SS8-312-1117-121-9Note b8-312-1117-121-024-4Spruce-Pine-Fir #18-112-816-720-323-67-911-414-417-720-4Spruce-Pine-Fir #28-112-816-720-323-67-911-414-417-720-4Spruce-Pine-Fir #36-99-1112-715-417-95-108-710-1013-315-524Douglas Fir-Larch SS8-313-017-221-10Note b8-313-016-720-323-5Douglas Fir-Larch #18-012-615-1019-522-67-510-1013-916-919-6Douglas Fir-Larch #27-1011-914-1018-221-06-1110-212-1015-818-3Douglas Fir-Larch #36-18-1011-313-815-115-37-89-911-1013-9Hem-Fir SS7-1023-316-220-825-17-1012-316-219-1023-0Hem-Fir #17-812-015-618-1121-117-310-713-516-419-0Hem-Fir #27-311-514-817-1020-96-1010-012-815-617-11Hem-Fir #36-18-1011-313-815-115-37-89-911-1013-9Southern Pine SS8-112-916-1021-6Note b8-112-916-1021-6Note bSouthern Pine #17-1012-316-218-1122-67-511-114-0 16-519-6Southern Pine #27-411-013-1116-619-66-49-612-1 14-416-10Southern Pine #35-88-410-612-915-14-117-39-1 11-013-1Spruce-Pine-Fir SS7-812-015-1020-224-77-812-015-418-921-9Spruce-Pine-Fir #17-611-914-1018-221-06-1110-212-1015-818-3Spruce-Pine-Fir #27-611-914-1018-221-06-1110-212-1015-818-3Spruce-Pine-Fir #36-18-1011-313-815-115-37-89-911-1013-9 Check sources for availability of lumber in lengths greater than 20 feet. For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square foot = 0.0479 kPa. a. The tabulated rafter spans assume that ceiling joists are located at the bottom of the attic space or that some other method of resisting the outward push of the rafters on the bearing walls, such as rafter ties, is provided at that location. Where ceiling joists or rafter ties are located higher in the attic space, the rafter spans shall be multiplied by the following factors: Hc/HRRafter Span Adjustment Factor1/30.671/40.761/50.831/60.901/7.5 or less1.00 where: Hc = Height of ceiling joists or rafter ties measured vertically above the top of the rafter support walls. HR = Height of roof ridge measured vertically above the top of the rafter support walls. b. Span exceeds 26 feet in length. Table 2308.7.2(3)Rafter Spans for Common Lumber Species(Ground Snow Load = 30 psf, Ceiling Not Attached to Rafters, L/Δ = 180) Rafter Spacing (inches)Species and GradeDead Load = 10 psfDead Load = 20 psf2 × 42 × 62 × 82 × 102 × 122 × 42 × 62 × 82 × 102 × 12Maximum rafter spans a(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)Rafter Spacing (inches)Species and GradeDead Load = 10 psfDead Load = 20 psf2 × 42 × 62 × 82 × 102 × 122 × 42 × 62 × 82 × 102 × 12Maximum rafter spans a(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)12Douglas Fir-Larch SS10-015-920-9Note bNote b10-015-920-124-6Note bDouglas Fir-Larch #19-814-918-822-9Note b9-013-216-820-423-7Douglas Fir-Larch #29-513-917-521-424-88-512-415-719-122-1Douglas Fir-Larch #37-110-513-216-118-86-49-411-914-516-8Hem-Fir SS9-614-1019-725-0Note b9-614-1019-724-1Note bHem-Fir #19-314-418-222-225-98-912-1016-319-1023-0Hem-Fir #28-1013-717-221-024-48-412-215-418-921-9Hem-Fir #37-110-513-216-118-86-49-411-914-516-8Southern Pine SS9-1015-620-5Note bNote b9-1015-620-5Note bNote bSouthern Pine #19-614-1019-022-326-09-013-517-0 19-1123-7Southern Pine #28-712-1116-419-522-107-811-714-817-420-5Southern Pine #36-79-912-415-017-95-118-911-0 13-515-10Spruce-Pine-Fir SS9-314-719-224-6Note b9-314-718-822-9Note bSpruce-Pine-Fir #19-113-917-521-424-88-512-415-719-122-1Spruce-Pine-Fir #29-113-917-521-424-88-512-415-719-122-1Spruce-Pine-Fir #37-110-513-216-118-86-49-411-914-516-816Douglas Fir-Larch SS9-114-418-1023-9Note b9-113-917-521-324-8Douglas Fir-Larch #18-912-916-219-922-107-1011-514-517-820-5Douglas Fir-Larch #28-211-1115-118-521-57-310-813-616-619-2Douglas Fir-Larch #36-29-011-513-1116-25-68-110-312-614-6Hem-Fir SS8-713-617-1022-9Note b8-713-617-120-1024-2Hem-Fir #18-512-515-919-322-37-711-114-117-219-11Hem-Fir #28-011-914-1118-221-17-210-613-416-318-10Hem-Fir #36-29-011-513-1116-25-68-110-312-614-6Southern Pine SS8-1114-118-623-8Note b8-1114-118-623-8Note bSouthern Pine #18-713-016-619-322-107-1011-714-9 17-320-5Southern Pine #27-611-214-216-1019-106-810-012-8 15-117-9Southern Pine #35-98-610-813-015-45-27-79-7 11-713-9Spruce-Pine-Fir SS8-513-317-522-125-78-512-916-219-922-10Spruce-Pine-Fir #18-211-1115-118-521-57-210-813-616-619-2Spruce-Pine-Fir #28-211-1115-118-521-57-310-813-616-619-2Spruce-Pine-Fir #36-29-011-513-1116-25-68-110-312-614-619.2Douglas Fir-Larch SS8-713-617-921-825-28-712-615-1019-522-6Douglas Fir-Larch #17-1111-814-918-020-117-110-513-216-118-8Douglas Fir-Larch #27-510-1113-916-1019-66-89-912-415-117-6Douglas Fir-Larch #35-78-310-512-914-95-07-49-411-513-2Hem-Fir SS8-112-916-921-424-88-112-415-719-122-1Hem-Fir #17-911-414-417-720-46-1110-212-1015-818-2Hem-Fir #27-410-913-716-719-36-79-712-214-1017-3Hem-Fir #35-78-310-512-914-95-07-49-411-513-2Southern Pine SS8-513-317-522-3Note b8-513-317-522-025-9Southern Pine #18-011-1015-117-720-117-110-713-5 15-918-8Southern Pine #26-1010-212-1115-418-16-19-211-7 13-916-2Southern Pine #35-37-99-911-1014-04-86-118-910-712-6Spruce-Pine-Fir SS7-1112-516-520-223-47-1111-814-918-020-11Spruce-Pine-Fir #17-510-1113-916-1019-66-89-912-415-117-6Spruce-Pine-Fir #27-510-1113-916-1019-66-89-912-415-117-6Spruce-Pine-Fir #35-78-310-512-914-95-07-49-411-513-224Douglas Fir-Larch SS7-1112-615-1019-522-67-811-314-217-420-1Douglas Fir-Larch #17-110-513-216-118-86-49-411-914-516-8Douglas Fir-Larch #26-89-912-415-117-65-118-811-013-615-7Douglas Fir-Larch #35-07-49-411-513-24-66-78-410-211-10Hem-Fir SS7-611-1015-719-122-17-611-013-1117-019-9Hem-Fir #16-1110-212-1015-818-26-29-111-614-016-3Hem-Fir #26-79-712-214-1017-35-108-710-1013-315-5Hem-Fir #35-07-49-411-513-24-66-78-410-211-10Southern Pine SS7-1012-316-220-825-17-1012-316-219-823-0Southern Pine #17-110-713-515-918-86-49-612-0 14-116-8Southern Pine #26-19-211-713-916-25-58-210-4 12-314-6Southern Pine #34-86-118-910-712-64-26-27-10 9-611-2Spruce-Pine-Fir SS7-411-714-918-020-117-110-513-216-118-8Spruce-Pine-Fir #16-89-912-415-117-65-118-811-013-615-7Spruce-Pine-Fir #26-89-912-415-117-65-118-811-013-615-7Spruce-Pine-Fir #35-07-49-411-513-24-66-78-410-211-10 Check sources for availability of lumber in lengths greater than 20 feet. For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square foot = 0.0479 kPa. a. The tabulated rafter spans assume that ceiling joists are located at the bottom of the attic space or that some other method of resisting the outward push of the rafters on the bearing walls, such as rafter ties, is provided at that location. Where ceiling joists or rafter ties are located higher in the attic space, the rafter spans shall be multiplied by the following factors: Hc/HRRafter Span Adjustment Factor1/30.671/40.761/50.831/60.901/7.5 or less1.00 where: Hc = Height of ceiling joists or rafter ties measured vertically above the top of the rafter support walls. HR = Height of roof ridge measured vertically above the top of the rafter support walls. b. Span exceeds 26 feet in length. Table 2308.7.2(4)Rafter Spans for Common Lumber Species(Ground Snow Load = 50 psf, Ceiling Not Attached to Rafters, L/Δ = 180) Rafter Spacing (inches)Species and GradeDead Load = 10 psfDead Load = 20 psf2 × 42 × 62 × 82 × 102 × 122 × 42 × 62 × 82 × 102 × 12Maximum rafter spans a(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)Rafter Spacing (inches)Species and GradeDead Load = 10 psfDead Load = 20 psf2 × 42 × 62 × 82 × 102 × 122 × 42 × 62 × 82 × 102 × 12Maximum rafter spans a(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)12Douglas Fir-Larch SS8-513-317-622-426-08-513-317-020-924-10Douglas Fir-Larch #18-212-015-318-721-77-711-214-117-320-0Douglas Fir-Larch #27-811-314-317-520-27-110-513-216-118-8Douglas Fir-Larch #35-108-610-913-215-35-57-1010-012-214-1Hem-Fir SS8-012-616-621-125-68-012-616-620-423-7Hem-Fir #17-1011-914-1018-121-07-510-1013-916-919-5Hem-Fir #27-511-114-017-219-117-010-313-015-1018-5Hem-Fir #35-108-610-913-215-35-57-1010-012-214-1Southern Pine SS8-413-117-221-11Note b8-413-117-221-525-3Southern Pine #18-012-315-618-221-77-711-414-5 16-1020-0Southern Pine #27-010-613-415-1018-86-69-912-414-817-3Southern Pine #35-58-010-112-314-65-07-59-4 11-413-5Spruce-Pine-Fir SS7-1012-316-220-824-17-1012-315-919-322-4Spruce-Pine-Fir #17-811-314-317-520-27-110-513-216-118-8Spruce-Pine-Fir #27-811-314-317-520-27-110-513-216-118-8Spruce-Pine-Fir #35-108-610-913-215-35-57-1010-012-214-116Douglas Fir-Larch SS7-812-115-1019-522-67-811-714-817-1120-10Douglas Fir-Larch #17-110-513-216-118-86-79-812-214-1117-3Douglas Fir-Larch #26-89-912-415-117-66-29-011-513-1116-2Douglas Fir-Larch #35-07-49-411-513-24-86-108-810-612-3Hem-Fir SS7-311-515-019-122-17-311-514-517-820-5Hem-Fir #16-1110-212-1015-818-26-59-511-1114-616-10Hem-Fir #26-79-712-214-1017-36-18-1113-313-915-11Hem-Fir #35-07-49-411-513-24-86-108-810-612-3Southern Pine SS7-611-1015-719-1123-77-611-1015-718-621-10Southern Pine #17-110-713-515-918-86-79-1012-5 14-717-3Southern Pine #26-19-211-713-916-25-88-510-9 12-915-0Southern Pine #34-86-118-910-712-64-46-58-1 9-1011-7Spruce-Pine-Fir SS7-111-214-818-020-117-110-913-816-819-4Spruce-Pine-Fir #16-89-912-415-117-66-29-011-513-1116-2Spruce-Pine-Fir #26-89-912-415-117-66-29-011-513-1116-2Spruce-Pine-Fir #35-07-49-411-513-24-86-108-810-612-319.2Douglas Fir-Larch SS7-311-414-617-820-67-310-713-516-519-0Douglas Fir-Larch #16-69-612-014-817-16-08-1011-213-715-9Douglas Fir-Larch #26-18-1111-313-915-115-78-310-512-914-9Douglas Fir-Larch #34-76-98-610-512-14-36-37-119-711-2Hem-Fir SS6-1010-914-217-520-26-1010-513-216-118-8Hem-Fir #16-49-311-914-416-75-108-710-1013-315-5Hem-Fir #26-08-911-113-715-95-78-110-312-714-7Hem-Fir #34-76-98-610-512-14-36-37-119-711-2Southern Pine SS7-111-214-818-321-77-111-214-2 16-1120-0Southern Pine #16-69-812-314-417-16-09-011-413-415-9Southern Pine #25-78-410-712-614-95-27-99-9 11-713-8Southern Pine #34-36-48-09-811-54-05-107-4 8-1110-7Spruce-Pine-Fir SS6-810-613-516-519-16-89-1012-515-317-8Spruce-Pine-Fir #16-18-1111-313-915-115-78-310-512-914-9Spruce-Pine-Fir #26-18-1111-313-915-115-78-310-512-914-9Spruce-Pine-Fir #34-76-98-610-512-14-36-37-119-711-224Douglas Fir-Larch SS6-810-313-015-1018-46-69-612-014-817-0Douglas Fir-Larch #15-108-610-913-215-35-57-1010-012-214-1Douglas Fir-Larch #25-57-1110-112-414-35-07-49-411-513-2Douglas Fir-Larch #34-16-07-79-410-93-105-77-18-710-0Hem-Fir SS6-49-1112-915-718-06-49-411-914-516-8Hem-Fir #15-88-310-612-1014-105-37-89-911-1013-9Hem-Fir #25-47-109-1112-114-14-117-39-211-313-0Hem-Fir #34-16-07-79-410-93-105-77-18-710-0Southern Pine SS6-710-413-816-419-36-710-013-8 15-217-10Southern Pine #15-108-811-012-1015-35-58-010-2 11-1114-1Southern Pine #25-07-59-511-313-24-76-118-910-512-3Southern Pine #33-105-87-18-810-33-65-36-7 8-09-6Spruce-Pine-Fir SS6-29-612-014-817-16-08-1011-213-715-9Spruce-Pine-Fir #15-57-1110-112-414-35-07-49-411-513-2Spruce-Pine-Fir #25-57-1110-112-414-35-07-49-411-513-2Spruce-Pine-Fir #34-16-07-79-410-93-105-77-18-710-0 Check sources for availability of lumber in lengths greater than 20 feet. For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square foot = 0.0479 kPa. a. The tabulated rafter spans assume that ceiling joists are located at the bottom of the attic space or that some other method of resisting the outward push of the rafters on the bearing walls, such as rafter ties, is provided at that location. Where ceiling joists or rafter ties are located higher in the attic space, the rafter spans shall be multiplied by the following factors: Hc/HRRafter Span Adjustment Factor1/30.671/40.761/50.831/60.901/7.5 or less1.00 where: Hc = Height of ceiling joists or rafter ties measured vertically above the top of the rafter support walls. HR = Height of roof ridge measured vertically above the top of the rafter support walls. b. Span exceeds 26 feet in length. Table 2308.7.2(5)Rafter Spans for Common Lumber Species(Ground Snow Load = 30 psf, Ceiling Attached to Rafters, L/Δ = 240) Rafter Spacing (inches)Species and GradeDead Load = 10 psfDead Load = 20 psf2 × 42 × 62 × 82 × 102 × 122 × 42 × 62 × 82 × 102 × 12Maximum rafter spans a(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)Rafter Spacing (inches)Species and GradeDead Load = 10 psfDead Load = 20 psf2 × 42 × 62 × 82 × 102 × 122 × 42 × 62 × 82 × 102 × 12Maximum rafter spans a(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)12Douglas Fir-Larch SS9-114-418-1024-1Note b9-114-418-1024-1Note bDouglas Fir-Larch #18-913-918-222-9Note b8-913-216-820-423-7Douglas Fir-Larch #28-713-617-521-424-88-512-415-719-122-1Douglas Fir-Larch #37-110-513-216-118-86-49-411-914-516-8Hem-Fir SS8-713-617-1022-9Note b8-713-617-1022-9Note bHem-Fir #18-513-317-522-225-98-512-1016-319-1023-0Hem-Fir #28-012-716-721-024-48-012-215-418-921-9Hem-Fir #37-110-513-216-118-86-49-411-914-516-8Southern Pine SS8-1114-118-623-8Note b8-1114-118-623-8Note bSouthern Pine #18-713-617-1022-3Note b8-713-517-0 19-1123-7Southern Pine #28-312-1116-419-522-107-811-714-817-420-5Southern Pine #36-79-912-415-017-95-118-911-0 13-515-10Spruce-Pine-Fir SS8-513-317-522-3Note b8-513-317-522-3Note bSpruce-Pine-Fir #18-312-1117-021-424-88-312-415-719-122-1Spruce-Pine-Fir #28-312-1117-021-424-88-312-415-719-122-1Spruce-Pine-Fir #37-110-513-216-118-86-49-411-914-516-816Douglas Fir-Larch SS8-313-017-221-10Note b8-313-017-221-324-8Douglas Fir-Larch #18-012-616-219-922-107-1011-514-517-820-5Douglas Fir-Larch #27-1011-1115-118-521-57-310-813-616-619-2Douglas Fir-Larch #36-29-011-513-1116-25-68-110-312-614-6Hem-Fir SS7-1012-316-220-825-17-1012-316-220-824-2Hem-Fir #17-812-015-919-322-37-711-114-117-219-11Hem-Fir #27-311-514-1118-221-17-210-613-416-318-10Hem-Fir #36-29-011-513-1116-25-68-110-312-614-6Southern Pine SS8-112-916-1021-6Note b8-112-916-1021-6Note bSouthern Pine #17-1012-316-219-322-107-1011-714-9 17-320-5Southern Pine #27-611-214-216-1019-106-810-012-8 15-117-9Southern Pine #35-98-610-813-015-45-27-79-7 11-713-9Spruce-Pine-Fir SS7-812-015-1020-224-77-812-015-1019-922-10Spruce-Pine-Fir #17-611-915-118-521-57-310-813-616-619-2Spruce-Pine-Fir #27-611-915-118-521-57-310-813-616-619-2Spruce-Pine-Fir #36-29-011-513-1116-25-68-110-312-614-619.2Douglas Fir-Larch SS7-912-316-120-725-07-912-315-1019-522-6Douglas Fir-Larch #17-611-814-918-020-117-110-513-216-118-8Douglas Fir-Larch #27-410-1113-916-1019-66-89-912-415-117-6Douglas Fir-Larch #35-78-310-512-914-95-07-49-411-513-2Hem-Fir SS7-411-715-319-523-77-411-715-319-122-1Hem-Fir #17-211-414-417-720-46-1110-212-1015-818-2Hem-Fir #26-1010-913-716-719-36-79-712-214-1017-3Hem-Fir #35-78-310-512-914-95-07-49-111-513-2Southern Pine SS7-812-015-1020-224-77-812-015-1020-224-7Southern Pine #17-411-715-117-720-117-110-713-5 15-918-8Southern Pine #26-1010-212-1115-418-16-19-211-7 13-916-2Southern Pine #35-37-99-911-1014-04-86-118-910-712-6Spruce-Pine-Fir SS7-211-414-1119-023-17-211-414-918-020-11Spruce-Pine-Fir #17-010-1113-916-1019-66-89-912-415-117-6Spruce-Pine-Fir #27-010-1113-916-1019-66-89-912-415-117-6Spruce-Pine-Fir #35-78-310-512-914-95-07-49-411-513-224Douglas Fir-Larch SS7-311-415-019-122-67-311-314-217-420-1Douglas Fir-Larch #17-010-513-216-118-86-49-411-914-516-8Douglas Fir-Larch #26-89-912-415-117-65-118-811-013-515-7Douglas Fir-Larch #35-07-49-411-513-24-66-78-410-211-10Hem-Fir SS6-1010-914-218-021-116-1010-913-1117-019-9Hem-Fir #16-810-212-1015-818-26-29-111-614-016-3Hem-Fir #26-49-712-214-1017-35-108-710-1013-315-5Hem-Fir #35-07-49-411-513-24-66-78-410-211-10Southern Pine SS7-111-214-818-922-107-111-214-818-922-10Southern Pine #16-1010-713-515-918-86-49-612-0 14-116-8Southern Pine #26-19-211-713-916-25-58-210-4 12-314-6Southern Pine #34-86-118-910-712-64-26-27-10 9-611-2Spruce-Pine-Fir SS6-810-613-1017-820-116-810-513-216-118-8Spruce-Pine-Fir #16-69-912-415-117-65-118-811-013-615-7Spruce-Pine-Fir #26-69-912-415-117-65-118-811-013-615-7Spruce-Pine-Fir #35-07-49-411-513-24-66-78-410-211-10 Check sources for availability of lumber in lengths greater than 20 feet. For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square foot = 0.0479 kPa. a. The tabulated rafter spans assume that ceiling joists are located at the bottom of the attic space or that some other method of resisting the outward push of the rafters on the bearing walls, such as rafter ties, is provided at that location. Where ceiling joists or rafter ties are located higher in the attic space, the rafter spans shall be multiplied by the following factors: Hc/HRRafter Span Adjustment Factor1/30.671/40.761/50.831/60.901/7.5 or less1.00 where: Hc = Height of ceiling joists or rafter ties measured vertically above the top of the rafter support walls. HR = Height of roof ridge measured vertically above the top of the rafter support walls. b. Span exceeds 26 feet in length. Table 2308.7.2(6)Rafter Spans for Common Lumber Species(Ground Snow Load = 50 psf, Ceiling Attached to Rafters, L/Δ = 240) Rafter Spacing (inches)Species and GradeDead Load = 10 psfDead Load = 20 psf2 × 42 × 62 × 82 × 102 × 122 × 42 × 62 × 82 × 102 × 12Maximum rafter spans a(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)Rafter Spacing (inches)Species and GradeDead Load = 10 psfDead Load = 20 psf2 × 42 × 62 × 82 × 102 × 122 × 42 × 62 × 82 × 102 × 12Maximum rafter spans a(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)(ft.-in.)12Douglas Fir-Larch SS7-812-115-1120-324-87-812-115-1120-324-0Douglas Fir-Larch #17-511-715-318-721-77-511-214-017-320-0Douglas Fir-Larch #27-311-314-317-520-27-110-513-216-118-8Douglas Fir-Larch #35-108-610-913-215-35-57-1010-012-214-1Hem-Fir SS7-311-515-019-223-47-311-815-019-223-4Hem-Fir #17-111-214-818-121-07-110-1013-916-919-5Hem-Fir #26-910-814-017-219-116-910-313-015-1018-5Hem-Fir #35-108-610-913-215-35-57-1010-012-214-1Southern Pine SS7-611-1015-719-1124-37-611-1015-719-1124-3Southern Pine #17-311-515-018-221-77-311-414-5 16-1020-0Southern Pine #26-1110-613-415-1018-86-69-912-414-817-3Southern Pine #35-58-010-112-314-65-07-59-4 11-413-5Spruce-Pine-Fir SS7-111-214-818-922-107-111-214-818-922-4Spruce-Pine-Fir #16-1110-1114-317-520-26-1110-513-216-118-8Spruce-Pine-Fir #26-1110-1114-317-520-26-1110-513-216-118-8Spruce-Pine-Fir #35-108-610-913-215-35-57-1010-012-214-116Douglas Fir-Larch SS7-011-014-518-522-57-011-014-517-1120-10Douglas Fir-Larch #16-910-513-216-118-86-79-812-214-1117-3Douglas Fir-Larch #26-79-912-415-117-66-29-011-513-1116-2Douglas Fir-Larch #35-07-49-411-513-24-86-108-810-612-3Hem-Fir SS6-710-413-817-521-26-710-413-817-520-5Hem-Fir #16-510-212-1015-818-26-59-511-1114-616-10Hem-Fir #26-29-712-214-1017-36-18-1111-313-915-11Hem-Fir #35-07-49-411-513-24-86-108-810-612-3Southern Pine SS6-1010-914-218-122-06-1010-914-218-121-10Southern Pine #16-710-413-515-918-86-79-1012-5 14-717-3Southern Pine #26-19-211-713-916-25-88-510-9 12-915-0Southern Pine #34-86-118-910-712-64-46-58-1 9-1011-7Spruce-Pine-Fir SS6-510-213-417-020-96-510-213-416-819-4Spruce-Pine-Fir #16-49-912-415-117-66-29-011-513-1116-2Spruce-Pine-Fir #26-49-912-415-117-66-29-011-513-1116-2Spruce-Pine-Fir #35-07-49-411-513-24-86-108-810-612-319.2Douglas Fir-Larch SS6-710-413-717-420-66-710-413-516-519-0Douglas Fir-Larch #16-49-612-014-817-16-08-1011-213-715-9Douglas Fir-Larch #26-18-1111-313-915-115-78-310-512-914-9Douglas Fir-Larch #34-76-98-610-512-14-36-37-119-711-2Hem-Fir SS6-29-912-1016-519-116-29-912-1016-118-8Hem-Fir #16-19-311-914-416-75-108-710-1013-315-5Hem-Fir #25-98-911-113-715-95-78-110-312-714-7Hem-Fir #34-76-98-610-512-14-36-37-119-711-2Southern Pine SS6-510-213-417-020-96-510-213-4 16-1120-0Southern Pine #16-29-812-314-417-16-09-011-413-415-9Southern Pine #25-78-410-712-614-95-27-99-9 11-713-8Southern Pine #34-36-48-09-811-54-05-107-4 8-1110-7Spruce-Pine-Fir SS6-19-612-716-019-16-19-612-515-317-8Spruce-Pine-Fir #15-118-1111-313-915-115-78-310-512-914-9Spruce-Pine-Fir #25-118-1111-313-915-115-78-310-512-914-9Spruce-Pine-Fir #34-76-98-610-512-14-36-37-119-711-224Douglas Fir-Larch SS6-19-712-715-1018-46-19-612-014-817-0Douglas Fir-Larch #15-108-610-913-215-35-57-1010-012-214-1Douglas Fir-Larch #25-57-1110-112-414-35-07-49-411-513-2Douglas Fir-Larch #34-16-07-79-410-93-105-77-18-710-0Hem-Fir SS5-99-111-1115-1218-05-99-111-914-516-8Hem-Fir #15-88-310-612-1014-105-37-89-911-1013-9Hem-Fir #25-47-109-1112-114-14-117-39-211-313-0Hem-Fir #34-16-107-79-410-93-105-77-18-710-0Southern Pine SS6-09-512-515-1019-36-09-512-515-217-10Southern Pine #15-98-811-012-1015-35-58-010-2 11-1114-1Southern Pine #25-07-59-511-313-24-76-118-910-512-3Southern Pine #33-105-87-18-810-33-65-36-7 8-09-6Spruce-Pine-Fir SS5-88-1011-814-817-15-88-1011-213-715-9Spruce-Pine-Fir #15-57-1110-112-414-35-07-49-411-513-2Spruce-Pine-Fir #25-57-1110-112-414-35-07-49-411-513-2Spruce-Pine-Fir #34-16-07-79-410-93-105-77-18-710-0 Check sources for availability of lumber in lengths greater than 20 feet. For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square foot = 0.0479 kPa. a. The tabulated rafter spans assume that ceiling joists are located at the bottom of the attic space or that some other method of resisting the outward push of the rafters on the bearing walls, such as rafter ties, is provided at that location. Where ceiling joists or rafter ties are located higher in the attic space, the rafter spans shall be multiplied by the following factors: Hc/HRRafter Span Adjustment Factor1/30.671/40.761/50.831/60.901/7.5 or less1.00 where: Hc = Height of ceiling joists or rafter ties measured vertically above the top of the rafter support walls. HR = Height of roof ridge measured vertically above the top of the rafter support walls. (Am. L.L. 2023/077, 6/11/2023, eff. 6/11/2023) Editor's note: For related unconsolidated provisions, see Appendix A at L.L. 2023/077.
