Wind-Borne Debris Region and certification reports
Wind-Borne Debris Region and certification reports for insurance companies and mortgage companies
free estimates
Jacksonville Duval County 904-346-1266
St Augustine St Johns County 904-824-7144
Orange Park Clay County 904-264-6444
Jacksonville Beaches Duval County 904-246-3969
Fernandina Nassau County 904-277-3040
Macclenny Baker County 904-259-5091
Palm Coast Flagler County 386-439-5290
Daytona Volusia County 386-253-4911
GAINESVILLE ALACHUA COUNTY 352-335-8555
Serving all of Florida and Georgia at 904-346-1266
EMAIL LARRY@1STPROP.COM (feel free to email your bidding packages here)
Impact of Wind-Borne Debris Requirements on Construction Practices
Note: The proposed Florida Building Code allows the use of partially enclosed/internal pressure design for protecting buildings from the impact of wind-borne debris.
The Florida Building Commission contracted several studies to determine the impact of wind-borne debris requirements on construction practices and costs. Data sources are American Forest and Paper Association (AfoPA), Florida Concrete and Products Association and Southern Building Code Congress International (SBCCI). The following is a summary of those study results. (Note: this analysis only addresses exposure B.)
- •No change to wall framing practices in wind regions under 130 mph.
- •No change to masonry reinforcement practices in wind regions under 130 mph.
- •No change to roof framing and sheathing practices in wind regions under 130 mph.
- •Additional connectors required. Material costs for 1500 sq. ft. house under $100.
Frame Wall Construction:
The attached tables show that conventional framing, #2 spruce, pine, fir, 2×4 16 o.c. fully sheathed with minimum structural panel, is sufficient for partially enclosed/internal pressure worst case design up to 125 mph for 10′ wall heights and 140+ mph for 8′ wall heights. (AFoPA National Wood Design Manual, High Wind Edition, draft revised tables for compliance with ASCE 7-98) [See example attached.]
Masonry Wall Construction:
The Florida Building Commission approved the Florida Concrete and Products Association prescriptive design method, Guide to Concrete Masonry Residential Construction in High Wind Areas for construction of one and two family residential buildings for basic wind speeds of 130 mph or less and exposure B.
Roof Construction:
The engineering analysis of Gary Walker, P.E. and the Southern Building Code Congress International show that common frame roofing with #2 SPF, 2×6, 24″ o.c. framing with 7/16″ minimum structural panel sheathing is sufficient to withstand the additional forces of partially enclosed/internal pressure worst case design.
Connectors: Additional roof anchorage will be needed for basic wind speeds 110 mph and above.
|
Example: Partially Enclosed, 2 x 4 @ 16 o/c Spruce – Pine – Fir #2 |
|||
| Wind Speed mph 3 sec gusts | Stud Length(from Table 3.20A) | Exposure BAdjustment Factor (.90) | Exposure CAdjustment Factor (.78) |
| 110 | 12′ – 1″ | (12′ – 1″) x (.9) = 10′ – 10″ | 9′ – 5″ |
| 120 | 11′ – 5″ | 10′ – 5″ | 8′ – 11″ |
| 130 | 10′ – 10″ | 9′ – 9″ | 8′ – 5″ |
| 140 | 10′ – 1″ | 9′ – 1″ | 7′ – 10″ |
| 150 | 9′ – 4″ | 8′ – 4″ | 7′ – 3″ |
Note: Exposure B – Suburban and wooded environment
Exposure C – Waterfront
mo\exposure.wpd
TABLE 3.20A
MAXIMUM EXTERIOR LOADBEARING AND NON-LOADBEARING STUD LENGTHS FOR COMMON LUMBER SPECIES RESISTING INTERIOR ZONE WIND LOADS
(Fully Sheathed with a Minimum Sheathing Material)a
| Three Second Gust Wind Speed (mph) | 85 | 90 | 100 | 110 | ||||||||||
| Stud Spacing (in.) |
Species | Grade | 2×4 | 2×6 | 2×8 | 2×4 | 2×6 | 2×8 | 2×4 | 2×6 | 2×8 | 2×4 | 2×6 | 2×8 |
| Maximum Allowable Stud Length (ft.-in.)1 | ||||||||||||||
| 12 | Douglas Fir-LarchDouglas Fir-Larch
Douglas Fir-Larch Douglas Fir-Larch Douglas Fir-Larch Hem-Fir Hem-Fir Hem-Fir Hem-Fir Hem-Fir Southern Pine Southern Pine Southern Pine Southern Pine Southern Pine Spruce-Pine-Fir Spruce-Pine-Fir Spruce-Pine-Fir Spruce-Pine-Fir Spruce-Pine-Fir |
SS#1
#2 Stud Standard SS #1 #2 Stud Standard SS #1 #2 Stud Standard SS #1 #2 Stud Standard |
17-716-11
16-7 15-2 12-7 16-7 16-3 15-6 15-1 12-7 17-3 16-11 16-7 15-10 13-6 16-3 15-10 15-10 15-1 12-7 |
20-020-0
20-0 20-0 – 20-0 20-0 20-0 20-0 – 20-0 20-0 20-0 20-0 – 20-0 20-0 20-0 20-0 – |
20-020-0
20-0 20-0 – 20-0 20-0 20-0 20-0 – 20-0 20-0 20-0 20-0 – 20-0 20-0 20-0 20-0 – |
16-1116-3
15-11 14-3 11-10 15-11 15-7 14-11 14-3 11-10 16-7 16-3 15-11 14-11 12-8 15-7 15-3 15-3 14-3 11-10 |
20-020-0
20-0 20-0 – 20-0 20-0 20-0 20-0 – 20-0 20-0 20-0 20-0 – 20-0 20-0 20-0 20-0 – |
20-020-0
20-0 20-0 – 20-0 20-0 20-0 20-0 – 20-0 20-0 20-0 20-0 – 20-0 20-0 20-0 20-0 – |
15-915-2
14-10 12-9 10-7 14-10 14-7 13-10 12-9 10-7 15-6 15-2 14-10 13-4 11-4 14-7 14-3 14-3 12-9 10-7 |
20-020-0
20-0 19-2 – 20-0 20-0 20-0 19-2 – 20-0 20-0 20-0 20-0 – 20-0 20-0 20-0 19-2 – |
20-020-0
20-0 20-0 – 20-0 20-0 20-0 20-0 – 20-0 20-0 20-0 20-0 – 20-0 20-0 20-0 20-0 – |
14-914-3
13-11 11-6 9-7 13-11 13-8 13-0 11-6 9-7 14-6 14-3 13-11 12-1 10-3 13-8 13-4 13-4 11-6 9-7 |
20-020-0
20-0 17-4 – 20-0 20-0 20-0 17-4 – 20-0 20-0 20-0 18-4 – 20-0 20-0 20-0 17-4 – |
20-020-0
20-0 20-0 – 20-0 20-0 20-0 20-0 – 20-0 20-0 20-0 20-0 – 20-0 20-0 20-0 20-0 – |
|
16 |
Douglas Fir-LarchDouglas Fir-Larch
Douglas Fir-Larch Douglas Fir-Larch Douglas Fir-Larch Hem-Fir Hem-Fir Hem-Fir Hem-Fir Hem-Fir Southern Pine Southern Pine Southern Pine Southern Pine Southern Pine Spruce-Pine-Fir Spruce-Pine-Fir Spruce-Pine-Fir Spruce-Pine-Fir Spruce-Pine-Fir |
SS#1
#2 Stud Standard SS #1 #2 Stud Standard SS #1 #2 Stud Standard SS #1 #2 Stud Standard |
15-1115-4
15-1 13-0 10-10 15-1 14-9 14-1 13-0 10-10 15-8 15-4 15-1 13-7 11-7 14-9 14-5 14-5 13-0 10-10 |
20-020-0
20-0 19-7 – 20-0 20-0 20-0 19-7 – 20-0 20-0 20-0 20-0 – 20-0 20-0 20-0 19-7 – |
20-020-0
20-0 20-0 – 20-0 20-0 20-0 20-0 – 20-0 20-0 20-0 20-0 – 20-0 20-0 20-0 20-0 – |
15-414-9
14-6 12-3 10-2 14-6 14-2 13-6 12-3 10-2 15-1 14-9 14-6 12-10 10-10 14-2 13-10 13-10 12-3 10-2 |
20-020-0
20-0 18-5 – 20-0 20-0 20-0 18-5 – 20-0 20-0 20-0 19-6 – 20-0 20-0 20-0 18-5 – |
20-020-0
20-0 20-0 – 20-0 20-0 20-0 20-0 – 20-0 20-0 20-0 20-0 – 20-0 20-0 20-0 20-0 – |
14-413-9
13-6 10-11 9-1 13-6 13-3 12-7 10-11 9-1 14-1 13-9 13-6 11-5 9-9 13-3 12-11 12-11 10-11 9-1 |
20-020-0
20-0 16-5 – 20-0 20-0 19-10 16-5 – 20-0 20-0 20-0 17-5 – 20-0 20-0 20-0 16-5 – |
20-020-0
20-0 20-0 – 20-0 20-0 20-0 20-0 – 20-0 20-0 20-0 20-0 – 20-0 20-0 20-0 20-0 – |
13-512-11
12-8 9-10 8-2 12-8 12-5 11-10 9-10 8-2 13-2 12-11 12-8 10-4 8-9 12-5 12-1 12-1 9-10 8-2 |
20-020-0
19-7 14-10 – 19-11 19-6 18-7 14-10 – 20-0 20-0 19-11 15-8 – 19-6 19-1 19-1 14-10 – |
20-020-0
20-0 19-1 – 20-0 20-0 20-0 19-1 – 20-0 20-0 20-0 20-0 – 20-0 20-0 20-0 19-1 – |
|
24 |
Douglas Fir-LarchDouglas Fir-Larch
Douglas Fir-Larch Douglas Fir-Larch Douglas Fir-Larch Hem-Fir Hem-Fir Hem-Fir Hem-Fir Hem-Fir Southern Pine Southern Pine Southern Pine Southern Pine Southern Pine Spruce-Pine-Fir Spruce-Pine-Fir Spruce-Pine-Fir Spruce-Pine-Fir Spruce-Pine-Fir |
SS#1
#2 Stud Standard SS #1 #2 Stud Standard SS #1 #2 Stud Standard SS #1 #2 Stud Standard |
13-1113-5
13-2 10-6 8-8 13-2 12-10 12-3 10-6 8-8 13-8 13-5 13-2 11-0 9-4 12-10 12-7 12-7 10-6 8-8 |
20-020-0
20-0 15-9 – 20-0 20-0 19-3 15-9 – 20-0 20-0 20-0 16-8 – 20-0 19-9 19-9 15-9 – |
20-020-0
20-0 20-0 – 20-0 20-0 20-0 20-0 – 20-0 20-0 20-0 20-0 – 20-0 20-0 20-0 20-0 – |
13-512-11
12-8 9-10 8-2 12-8 12-5 11-10 9-10 8-2 13-2 12-11 12-8 10-4 8-9 12-5 12-1 12-1 9-10 8-2 |
20-020-0
19-7 14-9 – 19-11 19-6 18-7 14-9 – 20-0 20-0 19-11 15-8 – 19-6 19-0 19-0 14-9 – |
20-020-0
20-0 19-1 – 20-0 20-0 20-0 19-1 – 20-0 20-0 20-0 20-0 – 20-0 20-0 20-0 19-1 – |
12-612-0
11-7 8-9 – 11-10 11-7 11-0 8-9 – 12-3 12-0 11-10 9-3 7-10 11-7 11-3 11-3 8-9 – |
19-818-9
17-6 13-2 – 18-7 18-2 17-3 13-2 – 19-3 18-11 18-5 14-0 – 18-2 17-6 17-6 13-2 – |
20-020-0
20-0 17-0 – 20-0 20-0 20-0 17-0 – 20-0 20-0 20-0 18-1 – 20-0 20-0 20-0 17-0 – |
11-911-3
10-6 7-11 – 11-1 10-10 10-4 7-11 – 11-6 11-4 11-1 8-4 – 10-10 10-6 10-6 7-11 – |
18-516-11
15-9 11-11 – 17-5 16-6 15-6 11-11 – 18-1 17-9 16-7 12-7 – 17-0 15-9 15-9 11-11 – |
20-020-0
20-0 15-4 – 20-0 20-0 20-0 15-4 – 20-0 20-0 20-0 16-4 – 20-0 20-0 20-0 15-4 – |
| – Lumber grade not available or allowable stud length is less than 7′-9″ (For 8′ wall height).a Maximum stud lengths in Table 3.20A are based on interior zone loads and assume that all studs are sheathed with a minimum sheathing material. Studs within 4′ of corners shall be sheathed on the exterior with a minimum of 3/8″ wood structural panels and on the interior with a minimum sheathing material, or stud spacings shall be multiplied by 0.85 for framing located within 4′ of corners to account for the additional end zone loding requirements. The additional bending capacity provided by the wood structural panels or reduced stud spacing is assumed to be sufficient to resist the additional end zone loading requirements.
See Footnote 1 |
||||||||||||||
TABLE 3.20A
MAXIMUM EXTERIOR LOADBEARING AND NON-LOADBEARING STUD LENGTHS FOR COMMON LUMBER SPECIES RESISTING INTERIOR ZONE WIND LOADS
(Fully Sheathed with a Minimum Sheathing Material)a
| Three Second Gust Wind Speed (mph) | 120 | 130 | 140 | 150 | ||||||||||
| Stud Spacing (in.) |
Species | Grade | 2×4 | 2×6 | 2×8 | 2×4 | 2×6 | 2×8 | 2×4 | 2×6 | 2×8 | 2×4 | 2×6 | 2×8 |
| Maximum Allowable Stud Length (ft.-in.)1 | ||||||||||||||
| 12 | Douglas Fir-LarchDouglas Fir-Larch
Douglas Fir-Larch Douglas Fir-Larch Douglas Fir-Larch Hem-Fir Hem-Fir Hem-Fir Hem-Fir Hem-Fir Southern Pine Southern Pine Southern Pine Southern Pine Southern Pine Spruce-Pine-Fir Spruce-Pine-Fir Spruce-Pine-Fir Spruce-Pine-Fir Spruce-Pine-Fir |
SS#1
#2 Stud Standard SS #1 #2 Stud Standard SS #1 #2 Stud Standard SS #1 #2 Stud Standard |
13-1113-5
13-2 10-6 8-8 13-2 12-11 12-3 10-6 8-8 13-8 13-5 13-2 11-0 9-4 12-11 12-7 12-7 10-6 8-8 |
20-020-0
20-0 15-9 – 20-0 20-0 19-4 15-9 – 20-0 20-0 20-0 16-8 – 20-0 19-9 19-9 15-9 – |
20-020-0
20-0 20-0 – 20-0 20-0 20-0 20-0 – 20-0 20-0 20-0 20-0 – 20-0 20-0 20-0 20-0 – |
13-312-9
12-6 9-8 8-0 12-6 12-3 11-8 9-8 8-0 13-0 12-9 12-6 10-1 8-7 12-3 11-11 11-11 9-8 8-0 |
20-020-0
19-2 14-5 – 19-7 19-2 18-4 14-5 – 20-0 20-0 19-7 15-4 – 19-2 18-9 18-9 14-5 – |
20-020-0
20-0 18-8 – 20-0 20-0 20-0 18-8 – 20-0 20-0 20-0 19-10 – 20-0 20-0 20-0 18-8 – |
12-712-1
11-9 8-11 – 11-11 11-8 11-1 8-11 – 12-4 12-1 11-11 9-4 7-11 11-8 11-4 11-4 8-11 – |
19-919-0
17-8 13-4 – 18-8 18-3 17-5 13-4 – 19-5 19-1 18-7 14-2 – 18-3 17-8 17-8 13-4 – |
20-020-0
20-0 17-2 – 20-0 20-0 20-0 17-2 – 20-0 20-0 20-0 18-4 – 20-0 20-0 20-0 17-2 – |
12-011-7
10-11 8-3 – 11-4 11-1 10-7 8-3 – 11-10 11-7 11-4 8-8 – 11-1 10-10 10-10 8-3 – |
18-1117-8
16-5 12-5 – 17-10 17-2 16-2 12-5 – 18-7 18-2 17-3 13-1 – 17-5 16-5 16-5 12-5 – |
20-020-0
20-0 16-0 – 20-0 20-0 20-0 16-0 – 20-0 20-0 20-0 17-0 – 20-0 20-0 20-0 16-0 – |
|
16 |
Douglas Fir-LarchDouglas Fir-Larch
Douglas Fir-Larch Douglas Fir-Larch Douglas Fir-Larch Hem-Fir Hem-Fir Hem-Fir Hem-Fir Hem-Fir Southern Pine Southern Pine Southern Pine Southern Pine Southern Pine Spruce-Pine-Fir Spruce-Pine-Fir Spruce-Pine-Fir Spruce-Pine-Fir Spruce-Pine-Fir |
SS#1
#2 Stud Standard SS #1 #2 Stud Standard SS #1 #2 Stud Standard SS #1 #2 Stud Standard |
12-812-2
11-11 9-0 – 12-0 11-8 11-2 9-0 – 12-5 12-2 12-0 9-5 8-0 11-8 11-5 11-5 9-0 – |
19-1119-2
17-10 13-6 – 18-10 18-5 17-6 13-6 – 19-7 19-2 18-10 14-3 – 18-5 17-10 17-10 13-6 – |
20-020-0
20-0 17-5 – 20-0 20-0 20-0 17-5 – 20-0 20-0 20-0 18-6 – 20-0 20-0 20-0 17-5 – |
12-011-7
10-11 8-3 – 11-4 11-1 10-7 8-3 – 11-10 11-7 11-4 8-8 – 11-1 10-10 10-10 8-3 – |
18-1017-7
16-5 12-5 – 17-10 17-2 16-2 12-5 – 18-6 18-2 17-3 13-1 – 17-5 16-5 16-5 12-5 – |
20-020-0
20-0 16-0 – 20-0 20-0 20-0 16-0 – 20-0 20-0 20-0 17-0 – 20-0 20-0 20-0 16-0 – |
11-510-10
10-1 – – 10-10 10-6 9-11 – – 11-3 11-0 10-10 8-0 – 10-7 10-1 10-1 – – |
18-016-3
15-2 11-5 – 17-0 15-10 14-11 11-5 – 17-8 17-4 15-11 12-1 – 16-7 15-2 15-2 11-5 – |
20-020-0
19-6 14-9 – 20-0 20-0 19-3 14-9 – 20-0 20-0 20-0 15-8 – 20-0 19-6 19-6 14-9 – |
10-1110-1
9-4 – – 10-4 9-9 9-3 – – 10-9 10-6 10-1 – – 10-1 9-4 9-4 – – |
17-215-1
14-1 10-8 – 16-2 14-8 13-10 10-8 – 16-10 16-6 14-9 11-3 – 15-10 14-1 14-1 10-8 – |
20-019-6
18-1 13-8 – 20-0 18-11 17-10 13-8 – 20-0 20-0 19-6 14-7 – 20-0 18-1 18-1 13-8 – |
|
24 |
Douglas Fir-LarchDouglas Fir-Larch
Douglas Fir-Larch Douglas Fir-Larch Douglas Fir-Larch Hem-Fir Hem-Fir Hem-Fir Hem-Fir Hem-Fir Southern Pine Southern Pine Southern Pine Southern Pine Southern Pine Spruce-Pine-Fir Spruce-Pine-Fir Spruce-Pine-Fir Spruce-Pine-Fir Spruce-Pine-Fir |
SS#1
#2 Stud Standard SS #1 #2 Stud Standard SS #1 #2 Stud Standard SS #1 #2 Stud Standard |
11-110-3
9-7 – – 10-5 10-0 9-5 – – 10-10 10-8 10-3 – – 10-3 9-7 9-7 – – |
17-515-5
14-4 10-10 – 16-5 15-0 14-2 10-10 – 17-1 16-9 15-1 11-6 – 16-1 14-4 14-4 10-10 – |
20-019-11
18-6 14-0 – 20-0 19-4 18-3 14-0 – 20-0 20-0 19-11 14-11 – 20-0 18-6 18-6 14-0 – |
10-69-5
8-9 – – 9-11 9-2 8-8 – – 10-4 10-1 9-5 – – 9-8 8-9 8-9 – – |
16-614-2
13-2 10-0 – 15-7 13-9 13-0 10-0 – 16-2 15-11 13-10 10-7 – 15-3 13-2 13-2 10-0 – |
20-018-3
17-0 12-10 – 20-0 17-9 16-9 12-10 – 20-0 20-0 18-3 13-8 – 20-0 17-0 17-0 12-10 – |
10-08-9
8-1 – – 9-5 8-6 8-0 – – 9-10 9-7 8-9 – – 9-3 8-1 8-1 – – |
15-813-1
12-2 9-3 – 14-10 12-9 12-0 9-3 – 15-5 14-10 12-10 9-9 – 14-6 12-2 12-2 9-3 – |
20-016-10
15-8 11-10 – 19-6 16-5 15-5 11-10 – 20-0 19-0 16-10 12-8 – 19-0 15-8 15-8 11-10 – |
9-68-1
– – – 9-0 7-11 – – – 9-4 9-1 8-1 – – 8-10 – – – – |
14-1012-2
11-4 8-7 – 14-2 11-10 11-2 8-7 – 14-9 13-10 11-11 9-1 – 13-8 11-4 11-4 8-7 – |
19-115-8
14-7 11-0 – 18-8 15-3 14-4 11-0 – 19-5 17-8 15-8 11-9 – 17-8 14-7 14-7 11-0 – |
| – Lumber grade not available or allowable stud length is less than 7′-9″ (For 8′ wall height).a Maximum stud lengths in Table 3.20A are based on interior zone loads and assume that all studs are sheathed with a minimum sheathing material. Studs within 4′ of corners shall be sheathed on the exterior with a minimum of 3/8″ wood structural panels and on the interior with a minimum sheathing material, or stud spacings shall be multiplied by 0.85 for framing located within 4′ of corners to account for the additional end zone loding requirements. The additional bending capacity provided by the wood structural panels or reduced stud spacing is assumed to be sufficient to resist the additional end zone loading requirements.
See Footnote 1 |
||||||||||||||
stjohns2007
TABLE 3.20B
MAXIMUM EXTERIOR LOADBEARING AND NON-LOADBEARING STUD LENGTHS FOR COMMON LUMBER SPECIES RESISTING INTERIOR ZONE WIND LOADS
(Fully Sheathed with a Minimum of 3/8″ Wood Structural Panels)a
| Three Second Gust Wind Speed (mph) | 85 | 90 | 100 | 110 | ||||||||||
| Stud Spacing (in.) |
Species | Grade | 2×4 | 2×6 | 2×8 | 2×4 | 2×6 | 2×8 | 2×4 | 2×6 | 2×8 | 2×4 | 2×6 | 2×8 |
| Maximum Allowable Stud Length (ft.-in.)1 | ||||||||||||||
|
12 |
Douglas Fir-LarchDouglas Fir-Larch
Douglas Fir-Larch Douglas Fir-Larch Douglas Fir-Larch Hem-Fir Hem-Fir Hem-Fir Hem-Fir Hem-Fir Southern Pine Southern Pine Southern Pine Southern Pine Southern Pine Spruce-Pine-Fir Spruce-Pine-Fir Spruce-Pine-Fir Spruce-Pine-Fir Spruce-Pine-Fir |
SS#1
#2 Stud Standard SS #1 #2 Stud Standard SS #1 #2 Stud Standard SS #1 #2 Stud Standard |
17-716-11
16-7 15-10 14-6 16-7 16-3 15-6 15-1 14-6 17-3 16-11 16-7 15-10 15-6 16-3 15-10 15-10 15-1 14-6 |
20-020-0
20-0 20-0 – 20-0 20-0 20-0 20-0 – 20-0 20-0 20-0 20-0 – 20-0 20-0 20-0 20-0 – |
20-020-0
20-0 20-0 – 20-0 20-0 20-0 20-0 – 20-0 20-0 20-0 20-0 – 20-0 20-0 20-0 20-0 – |
16-1116-3
15-11 15-3 13-8 15-11 15-7 14-11 14-6 13-8 16-7 16-3 15-11 15-3 14-7 15-7 15-3 15-3 14-6 13-8 |
20-020-0
20-0 20-0 – 20-0 20-0 20-0 20-0 – 20-0 20-0 20-0 20-0 – 20-0 20-0 20-0 20-0 – |
20-020-0
20-0 20-0 – 20-0 20-0 20-0 20-0 – 20-0 20-0 20-0 20-0 – 20-0 20-0 20-0 20-0 – |
15-915-2
14-10 14-3 12-2 14-10 14-7 13-10 13-6 12-2 15-6 15-2 14-10 14-3 13-1 14-7 14-3 14-3 13-6 12-2 |
20-020-0
20-0 20-0 – 20-0 20-0 20-0 20-0 – 20-0 20-0 20-0 20-0 – 20-0 20-0 20-0 20-0 – |
20-020-0
20-0 20-0 – 20-0 20-0 20-0 20-0 – 20-0 20-0 20-0 20-0 – 20-0 20-0 20-0 20-0 – |
14-914-3
13-11 13-3 11-0 13-11 13-8 13-0 12-8 11-0 14-6 14-3 13-11 13-4 11-9 13-8 13-4 13-4 12-8 11-0 |
20-020-0
20-0 18-10 – 20-0 20-0 20-0 18-10 – 20-0 20-0 20-0 19-11 – 20-0 20-0 20-0 18-10 – |
20-020-0
20-0 20-0 – 20-0 20-0 20-0 20-0 – 20-0 20-0 20-0 20-0 – 20-0 20-0 20-0 20-0 – |
| 16 | Douglas Fir-LarchDouglas Fir-Larch
Douglas Fir-Larch Douglas Fir-Larch Douglas Fir-Larch Hem-Fir Hem-Fir Hem-Fir Hem-Fir Hem-Fir Southern Pine Southern Pine Southern Pine Southern Pine Southern Pine Spruce-Pine-Fir Spruce-Pine-Fir Spruce-Pine-Fir Spruce-Pine-Fir Spruce-Pine-Fir |
SS#1
#2 Stud Standard SS #1 #2 Stud Standard SS #1 #2 Stud Standard SS #1 #2 Stud Standard |
15-1115-4
15-1 14-5 12-5 15-1 14-9 14-1 13-8 12-5 15-8 15-4 15-1 14-5 13-4 14-9 14-5 14-5 13-8 12-5 |
20-020-0
20-0 20-0 – 20-0 20-0 20-0 20-0 – 20-0 20-0 20-0 20-0 – 20-0 20-0 20-0 20-0 – |
20-020-0
20-0 20-0 – 20-0 20-0 20-0 20-0 – 20-0 20-0 20-0 20-0 – 20-0 20-0 20-0 20-0 – |
15-414-9
14-6 13-10 11-8 14-6 14-2 13-6 13-2 11-8 15-1 14-9 14-6 13-10 12-6 14-2 13-10 13-10 13-2 11-8 |
20-020-0
20-0 20-0 – 20-0 20-0 20-0 20-0 – 20-0 20-0 20-0 20-0 – 20-0 20-0 20-0 20-0 – |
20-020-0
20-0 20-0 – 20-0 20-0 20-0 20-0 – 20-0 20-0 20-0 20-0 – 20-0 20-0 20-0 20-0 – |
14-413-9
13-6 12-7 10-5 13-6 13-3 12-7 12-3 10-5 14-1 13-9 13-6 12-11 11-2 13-3 12-11 12-11 12-3 10-5 |
20-020-0
20-0 17-11 – 20-0 20-0 19-10 17-11 – 20-0 20-0 20-0 18-11 – 20-0 20-0 20-0 17-11 – |
20-020-0
20-0 20-0 – 20-0 20-0 20-0 20-0 – 20-0 20-0 20-0 20-0 – 20-0 20-0 20-0 20-0 – |
13-512-11
12-8 11-4 9-5 12-8 12-5 11-10 11-4 9-5 13-2 12-11 12-8 11-11 10-1 12-5 12-1 12-1 11-4 9-5 |
20-020-0
19-11 16-2 – 19-11 19-6 18-7 16-2 – 20-0 20-0 19-11 17-1 – 19-6 19-1 19-1 16-2 – |
20-020-0
20-0 20-0 – 20-0 20-0 20-0 20-0 – 20-0 20-0 20-0 20-0 – 20-0 20-0 20-0 20-0 – |
| 24 | Douglas Fir-LarchDouglas Fir-Larch
Douglas Fir-Larch Douglas Fir-Larch Douglas Fir-Larch Hem-Fir Hem-Fir Hem-Fir Hem-Fir Hem-Fir Southern Pine Southern Pine Southern Pine Southern Pine Southern Pine Spruce-Pine-Fir Spruce-Pine-Fir Spruce-Pine-Fir Spruce-Pine-Fir Spruce-Pine-Fir |
SS#1
#2 Stud Standard SS #1 #2 Stud Standard SS #1 #2 Stud Standard SS #1 #2 Stud Standard |
13-1113-5
13-2 12-1 10-0 13-2 12-10 12-3 11-11 10-0 13-8 13-5 13-2 12-7 10-9 12-10 12-7 12-7 11-11 10-0 |
20-020-0
20-0 17-2 – 20-0 20-0 19-3 17-2 – 20-0 20-0 20-0 18-2 – 20-0 19-9 19-9 17-2 – |
20-020-0
20-0 20-0 – 20-0 20-0 20-0 20-0 – 20-0 20-0 20-0 20-0 – 20-0 20-0 20-0 20-0 – |
13-512-11
12-8 11-4 9-5 12-8 12-5 11-10 11-4 9-5 13-2 12-11 12-8 11-11 10-1 12-5 12-1 12-1 11-4 9-5 |
20-020-0
19-11 16-1 – 19-11 19-6 18-7 16-1 – 20-0 20-0 19-11 17-1 – 19-6 19-0 19-0 16-1 – |
20-020-0
20-0 19-11 – 20-0 20-0 20-0 19-11 – 20-0 20-0 20-0 20-0 – 20-0 20-0 20-0 19-11 – |
12-612-0
11-10 10-2 8-5 11-10 11-7 11-0 10-2 8-5 12-3 12-0 11-10 10-7 9-0 11-7 11-3 11-3 10-2 8-5 |
19-818-11
18-7 14-5 – 18-7 18-2 17-4 14-5 – 19-3 18-11 18-7 15-3 – 18-2 17-9 17-9 14-5 – |
20-020-0
20-0 17-10 – 20-0 20-0 20-0 17-10 – 20-0 20-0 20-0 18-11 – 20-0 20-0 20-0 17-10 – |
11-911-4
11-1 9-2 – 11-1 10-10 10-4 9-2 – 11-6 11-4 11-1 9-7 8-2 10-10 10-7 10-7 9-2 – |
18-517-9
17-2 13-0 – 17-5 17-0 16-3 13-0 – 18-1 17-9 17-5 13-9 – 17-0 16-8 16-8 13-0 – |
20-020-0
20-0 16-1 – 20-0 20-0 20-0 16-1 – 20-0 20-0 20-0 17-1 – 20-0 20-0 20-0 16-1 – |
| – Lumber grade not available or allowable stud length is less than 7′-9″ (For 8′ wall height).a Maximum stud lengths in Table 3.20B are based on interior zone loads and assume that all studs are sheathed on the exterior with a minimum of 3/8″ wood structural panels and on the interior with a minimum sheathing material. Stud spacings shall be multiplied by 0.85 for framing located within 4′ of corners to account for the additional end zone loading requirements.
See Footnote 1 |
||||||||||||||
TABLE 3.20B
MAXIMUM EXTERIOR LOADBEARING AND NON-LOADBEARING STUD LENGTHS FOR COMMON LUMBER SPECIES RESISTING INTERIOR ZONE WIND LOADS
(Fully Sheathed with a Minimum of 3/8″ Wood Structural Panels)a
| Three Second Gust Wind Speed (mph) | 120 | 130 | 140 | 150 | ||||||||||
| Stud Spacing (in.) |
Species | Grade | 2×4 | 2×6 | 2×8 | 2×4 | 2×6 | 2×8 | 2×4 | 2×6 | 2×8 | 2×4 | 2×6 | 2×8 |
| Maximum Allowable Stud Length (ft.-in.)1 | ||||||||||||||
| 12 | Douglas Fir-LarchDouglas Fir-Larch
Douglas Fir-Larch Douglas Fir-Larch Douglas Fir-Larch Hem-Fir Hem-Fir Hem-Fir Hem-Fir Hem-Fir Southern Pine Southern Pine Southern Pine Southern Pine Southern Pine Spruce-Pine-Fir Spruce-Pine-Fir Spruce-Pine-Fir Spruce-Pine-Fir Spruce-Pine-Fir |
SS#1
#2 Stud Standard SS #1 #2 Stud Standard SS #1 #2 Stud Standard SS #1 #2 Stud Standard |
13-1113-5
13-2 12-1 10-0 13-2 12-11 12-3 12-0 10-0 13-8 13-5 13-2 12-7 10-9 12-11 12-7 12-7 12-0 10-0 |
20-020-0
20-0 17-2 – 20-0 20-0 19-4 17-2 – 20-0 20-0 20-0 18-2 – 20-0 19-9 19-9 17-2 – |
20-020-0
20-0 20-0 – 20-0 20-0 20-0 20-0 – 20-0 20-0 20-0 20-0 – 20-0 20-0 20-0 20-0 – |
13-312-9
12-6 11-1 9-3 12-6 12-3 11-8 11-1 9-3 13-0 12-9 12-6 11-7 9-10 12-3 11-11 11-11 11-1 9-3 |
20-020-0
19-7 15-9 – 19-7 19-2 18-4 15-9 – 20-0 20-0 19-7 16-8 – 19-2 18-9 18-9 15-9 – |
20-020-0
20-0 19-6 – 20-0 20-0 20-0 19-6 – 20-0 20-0 20-0 20-0 – 20-0 20-0 20-0 19-6 – |
12-712-1
11-11 10-3 8-6 11-11 11-8 11-1 10-3 8-6 12-4 12-1 11-11 10-9 9-1 11-8 11-4 11-4 10-3 8-6 |
19-919-1
18-8 14-7 – 18-8 18-3 17-5 14-7 – 19-5 19-1 18-8 15-5 – 18-3 17-10 17-10 14-7 – |
20-020-0
20-0 18-0 – 20-0 20-0 20-0 18-0 – 20-0 20-0 20-0 19-2 – 20-0 20-0 20-0 18-0 – |
12-011-7
11-4 9-6 7-11 11-4 11-1 10-7 9-6 7-11 11-10 11-7 11-4 10-0 8-6 11-1 10-10 10-10 9-6 7-11 |
18-1118-2
17-10 13-6 – 17-10 17-5 16-8 13-6 – 18-7 18-2 17-10 14-4 – 17-5 17-1 17-1 13-6 – |
20-020-0
20-0 16-8 – 20-0 20-0 20-0 16-8 – 20-0 20-0 20-0 17-9 – 20-0 20-0 20-0 16-8 – |
| 16 | Douglas Fir-LarchDouglas Fir-Larch
Douglas Fir-Larch Douglas Fir-Larch Douglas Fir-Larch Hem-Fir Hem-Fir Hem-Fir Hem-Fir Hem-Fir Southern Pine Southern Pine Southern Pine Southern Pine Southern Pine Spruce-Pine-Fir Spruce-Pine-Fir Spruce-Pine-Fir Spruce-Pine-Fir Spruce-Pine-Fir |
SS#1
#2 Stud Standard SS #1 #2 Stud Standard SS #1 #2 Stud Standard SS #1 #2 Stud Standard |
12-812-2
12-0 10-4 8-7 12-0 11-8 11-2 10-4 8-7 12-5 12-2 12-0 10-10 9-3 11-8 11-5 11-5 10-4 8-7 |
19-1119-2
18-10 14-9 – 18-10 18-5 17-6 14-9 – 19-7 19-2 18-10 15-7 – 18-5 18-0 18-0 14-9 – |
20-020-0
20-0 18-2 – 20-0 20-0 20-0 18-2 – 20-0 20-0 20-0 19-4 – 20-0 20-0 20-0 18-2 – |
12-011-7
11-4 9-6 7-11 11-4 11-1 10-7 9-6 7-11 11-10 11-7 11-4 10-0 8-5 11-1 10-10 10-10 9-6 7-11 |
18-1018-2
17-10 13-6 – 17-10 17-5 16-8 13-6 – 18-6 18-2 17-10 14-3 – 17-5 17-1 17-1 13-6 – |
20-020-0
20-0 16-8 – 20-0 20-0 20-0 16-8 – 20-0 20-0 20-0 17-9 – 20-0 20-0 20-0 16-8 – |
11-511-0
10-10 8-9 – 10-10 10-7 10-1 8-9 – 11-3 11-0 10-10 9-2 7-10 10-7 10-4 10-4 8-9 – |
18-017-4
16-6 12-6 – 17-0 16-7 15-10 12-6 – 17-8 17-4 17-0 13-2 – 16-7 16-3 16-3 12-6 – |
20-020-0
20-0 15-5 – 20-0 20-0 20-0 15-5 – 20-0 20-0 20-0 16-5 – 20-0 20-0 20-0 15-5 – |
10-1110-6
10-4 8-2 – 10-4 10-1 9-7 8-2 – 10-9 10-6 10-4 8-7 – 10-1 9-10 9-10 8-2 – |
17-216-6
15-4 11-7 – 16-2 15-10 15-1 11-7 – 16-10 16-6 16-1 12-3 – 15-10 15-4 15-4 11-7 – |
20-020-0
18-11 14-4 – 20-0 19-10 18-8 14-4 – 20-0 20-0 20-0 15-3 – 20-0 18-11 18-11 14-4 – |
| 24 | Douglas Fir-LarchDouglas Fir-Larch
Douglas Fir-Larch Douglas Fir-Larch Douglas Fir-Larch Hem-Fir Hem-Fir Hem-Fir Hem-Fir Hem-Fir Southern Pine Southern Pine Southern Pine Southern Pine Southern Pine Spruce-Pine-Fir Spruce-Pine-Fir Spruce-Pine-Fir Spruce-Pine-Fir Spruce-Pine-Fir |
SS#1
#2 Stud Standard SS #1 #2 Stud Standard SS #1 #2 Stud Standard SS #1 #2 Stud Standard |
11-110-8
10-5 8-4 – 10-5 10-3 9-9 8-4 – 10-10 10-8 10-5 8-9 – 10-3 10-0 10-0 8-4 – |
17-516-9
15-8 11-10 – 16-5 16-1 15-4 11-10 – 17-1 16-9 16-5 12-6 – 16-1 15-8 15-8 11-10 – |
20-020-0
19-4 14-8 – 20-0 20-0 19-1 14-8 – 20-0 20-0 20-0 15-7 – 20-0 19-4 19-4 14-8 – |
10-610-1
9-11 – – 9-11 9-8 9-3 – – 10-4 10-1 9-11 8-0 – 9-8 9-6 9-6 – – |
16-615-5
14-4 10-10 – 15-7 15-0 14-2 10-10 – 16-2 15-11 15-1 11-6 – 15-3 14-4 14-4 10-10 – |
20-019-1
17-9 13-5 – 20-0 18-7 17-6 13-5 – 20-0 20-0 19-1 14-4 – 20-0 17-9 17-9 13-5 – |
10-09-7
9-4 – – 9-5 9-3 8-10 – – 9-10 9-7 9-5 – – 9-3 9-0 9-0 – – |
15-814-3
13-3 10-0 – 14-10 13-10 13-1 10-0 – 15-5 15-1 14-0 10-7 – 14-6 13-3 13-3 10-0 – |
20-017-8
16-5 12-5 – 19-6 17-2 16-2 12-5 – 20-0 19-11 17-8 13-2 – 19-1 16-5 16-5 12-5 – |
9-69-2
8-8 – – 9-0 8-10 8-5 – – 9-4 9-2 9-0 – – 8-10 8-7 8-7 – – |
15-013-3
12-4 9-4 – 14-2 12-11 12-2 9-4 – 14-9 14-5 13-0 9-10 – 13-10 12-4 12-4 9-4 – |
19-916-5
15-3 11-6 – 18-8 15-11 15-0 11-6 – 19-5 18-6 16-5 12-3 – 18-3 15-3 15-3 11-6 – |
| – Lumber grade not available or allowable stud length is less than 7′-9″ (For 8′ wall height).a Maximum stud lengths in Table 3.20B are based on interior zone loads and assume that all studs are sheathed on the exterior with a minimum of 3/8″ wood structural panels and on the interior with a minimum sheathing material. Stud spacings shall be multiplied by 0.85 for framing located within 4′ of corners to account for the additional end zone loading requirements.
See Footnote 1 |
||||||||||||||
Footnotes to Tables 3.20A&B
1 Maximum stud lengths in Tables 3.20A&B are based on wind loads. For dead and live loads, stud lengths shall be limited to the requirements in the following table:
| 2×3 | 2×4 | 2×5 | 2×6 | 2×8 | ||
| Maximum Unsupported Stud Length (ft.) | ||||||
| – | 10 | 10 | 10 | 10 | ||
| Loadbearing Studs Supporting: | Maximum Stud Spacing (in. o.c.) | |||||
| Roof & Ceiling Only 1 Floor Only
Roof, Ceiling & 1 Floor 2 Floors Only Roof, Ceiling & 2 Floors |
– –
– – – |
2424
16 16 – |
2424
16 16 – |
2424
24 24 16 |
2424
24 24 24 |
|
| stjohns2007 | Maximum Unsupported Stud Length (ft.) | |||||
| Non-loadbearing Studs | 10 | 14 | 16 | 20 | 20 | |
| Maximum Stud Spacing (in. o.c.) | ||||||
| 16 | 24 | 24 | 24 | 2 | ||
