Ga. Comp. R. & Regs. 110-11-1-.06
The following amendments to codes are hereby adopted by the Board of Community Affairs as amendments to the Georgia State Minimum Standard Codes for Construction:
GEORGIA AMENDMENTS TO THE
1994 STANDARD BUILDING CODE
Add to Section 202, Definitions, a definition for "Shearwall Segment" as follows:
SHEARWALL SEGMENT - a wall or portion thereof which transfers in plane lateral shear loads to a wall or foundation below and resists overturning.
* Said building code is further amended by adding an "Exception 5" to Section 1606.1.1 Determination of Wind Forces, as follows:
Exceptions:
5. Provisions of AF&PA "Wood Frame Construction Manual for One-and-Two Family dwellings - 1995 SBC High Wind Edition" shall be permitted for applicable wood frame buildings of Group R3 occupancy
* Said building code is further amended by adding a Section 2313 entitled "Perforated Shearwalls" as follows:
2313 Wind Provisions
2313.1 General
All buildings for which a wind analysis is required, according to 1606.1 and which are constructed partially or wholly of wood or wood based materials shall be designed in accordance with the provisions of 2313 and Chapter 23.
2313.2.1 Shearwall Segments
The total allowable shearwall capacity (lbs.) of each full-height shearwall segment without openings shall be equal to the allowable shear capacity (plf) times the length of the wall segment. Where the dead load stabilizing moment per 1606.4 is not sufficient to prevent overturning due to moment loads on the wall, an anchoring device with a capacity equal to the allowable shear capacity (p11) times the wall height shall be provided at each end of the shearwall segment. All anchoring devices shall maintain a continuous load path to the foundation. The capacity of shearwalls with openings shall be adjusted in accordance with 2313.2.2
2313.2.2 Openings in Shearwalls
Where openings are located within the shearwall segment, the wall shall be entirely sheathed with structural sheathing, including areas above and below openings. If areas above and below remain unsheathed, the height of the unrestrained openings shall be the height of the wall. The allowable shear capacity (p11) determined in 2313.2.1 shall be adjusted in accordance with Table 2313.2.2 based upon the maximum opening height and the percentage of shearwall segments containing full-height sheathing. The total allowable shear capacity (lbs.) shall be equal to the adjusted allowable shear capacity (plf) times the length of full-height sheathing.
Table 2313.2.2
Shear Capacity Adjustment Factors
Maximum Unrestrained Opening Height (H)(1)
(Window or Door Height)
H/3 | H/2 | 2H/3 | 5H/6 | H | |
8' Wall | 2'-8" | 4'-0" | 5'-4" | 6'-8" | 8'-0" |
10' Wall | 3'4" | 5'-0" | 6'-8" | 8'-4" | 10'-0" |
Percent
Full-Height Effective Shear Capacity Factors
Sheathing (2)
| 0% | 1.00 | 0.67 | 0.50 | 0.40 | 0.33 |
| 10% | 1.00 | 0.69 | 0.53 | 0.43 | 0.36 |
| 20% | 1.00 | 0.71 | 0.56 | 0.45 | 0.38 |
| 30% | 1.00 | 0.74 | 0.59 | 0.49 | 0.42 |
| 40% | 1.00 | 0.77 | 0.63 | 0.53 | 0.45 |
| 50% | 1.00 | 0.80 | 0.67 | 0.57 | 0.50 |
| 60% | 1.00 | 0.83 | 0.71 | 0.63 | 0.56 |
| 70% | 1.00 | 0.87 | 0.77 | 0.69 | 0.63 |
| 80% | 1.00 | 0.91 | 0.83 | 0.77 | 0.71 |
| 90% | 1.00 | 0.95 | 0.91 | 0.87 | 0.83 |
| 100% | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 |
1. H - the height of the tallest opening in the shearwall.
2. The sum of the length of a shearwall that is sheathed its full height divided by the length of the shearwall segment.
2313.2.3 Shear Capacities of Dissimilar Materials.
The allowable shear capacity of shearwall segments sheathed on both sides, with similar or dissimilar materials, shall equal the sum of the shear capacity of each separate side.
2313.2.4 Wood Structural Panel Diaphragm Shear Capacities.
The allowable shear capacities in Table 23 l0.2A for horizontal wood structural panel diaphragms shall be increased 40 percent for wind design.
2313.2.5 Wood Structural Panel Shear Wall Capacities.
The allowable shear capacities in Table 23 l0.2B for wood structural panel shear walls shall be increased 40 percent for wind design.
2313.3 Wall Stud Bending Stress Increases
The fiber stress bending (Fb) design values for wood studs, in the NDS supplement shall be increased by the factors in Table 2313.3, in lieu of the 1.15 repetitive member factor to take into consideration the load sharing and composite actions provided by the structural sheathing. Where the studs are designed for bending in accordance with 1606.2.5, spaced no more than 16 inches on center, covered on the inside with a minimum of 1/2 inch gypsum board fastened in accordance with Table 2306.1, or its equivalent, and sheathed with a minimum of 3/8 inch structural sheathing that is attached to the studs using a minimum of 8d common nails spaced a maximum of 6" o.c. at panel edges and 12" o.c. in the field of the panels.
Table 2313.3
Wall Stud Bending Stress Increase Factors
| Stud Size | System Factor |
| 2x4 | 1.5 |
| 2x6 | 1.4 |
| 2x8 | 1.3 |
| 2x10 | 1.2 |
| 2x12 | 1.15 |
GEORGIA AMENDMENTS TO THE
1995 CABO ONE-AND-TWO FAMILY DWELLING CODE
* Section 502.3 of the 155 CABO One-and-Two Family Dwelling Code is amended to read as follows:
502.3 Allowable spans.
Joists, girders and floor sheathing shall comply with Sections 502.3.1 through 502.3.3 and Section 503 or AF&PA "Wood Frame Construction Manual for One-and-Two Family Dwellings - 1995 SBC High Wind Edition."
* Said CABO Code is further amended by amending Section 602.3 to read as follows:
602.3 Exterior Walls.
Exterior walls of wood-frame construction shall be designed and constructed in accordance with the provisions of this chapter and Figures 602.3a and 602.3b or in accordance with the provisions of AF&PA "Wood Frame Construction Manual for One-and-Two Family Dwellings - 1995 SBC High Wind Edition."
* Said CABO Code is further amended by amending Section 802.2 to read as follows:
802.2 Design and construction
Roof Ceilings of wood construction shall be designed and constructed in accordance with the provisions of this chapter, or with the "AF&PA NDS-1991 "National Design Specifications for Wood Construction", the "CWC-1987 'Canadian Dimension Lumber Data Book", the "WWPA- 1992 Western Lumber Span Tables for Floor and Ceiling Joists and Roof Rafters", the "Southern Pine Maximum Spans for Joists and Rafters" or the AF&PA "Wood Frame Construction Manual for One-and-Two Family Dwellings - 1995 SBC High Wind Edition".
* Said CABO Code is further amended by adding the following Reference Standard to Section 4702:
Section 4702
Referenced Standards
AF&PA. Wood Frame Construction Manual for One-and-Two Family Dwellings - 1995- SBC High Wind Edition.
Ga. Comp. R. & Regs. R. 110-11-1-.06
O.C.G.A. Sec. 8-2-20.