Exception: A retrofit stud need not be added where the distance between it and an adjacent retrofit, primary stud would be less than 141/2 inches (368 mm).
1706.2 Piggyback Trusses
Primary studs of piggyback truss assemblies shall have retrofit studs sized and placed such that a single continuous retrofit stud is installed and fastened to the primary stud of both the lower and upper truss. Added studs shall be placed and fastened in accordance with Section 1705. The bottom chord of the upper truss shall be connected to the retrofit stud using an approved connector with minimum tension capacity of 175 pounds (79 kg).
1706.3.4 Method (d): Nailer With Retrofit Stud Method
Retrofit studs and existing studs shall be connected using minimum 2 × 4 nailers as indicated in Figure 1706.3(d), provided the following conditions are met. Nailers may be comprised of multiple members lengthwise.
Both the primary stud and the retrofit stud shall be butted to nailers and both shall be fastened to the nailer with 3-inch fasteners. Fasteners connecting each stud to the nailer shall be spaced 6-inches (152 mm) on center.
Fasteners into nailers through the face of either member shall be offset vertically by a minimum of 23/4 inches (70 mm).
Fasteners into nailers shall be a minimum of 23/4 inches (70 mm) but not more than 6 inches (152 mm) from the end of the shorter of the primary stud or retrofit stud to which they are fastened.
Fasteners shall be placed a minimum 1/2 inch (13 mm) from the edges of studs.
1706.4 Attachment of Retrofit Studs to Primary Studs
Where retrofit studs are placed using the methods of Section 1706.3.1 or 1706.3.4, retrofit studs shall be attached to primary studs and nailers shall be attached to primary studs and retrofit studs using minimum 3-inch long fasteners. Fastener penetration into each member shall be a minimum 11/2 inches (38 mm). Fasteners can be installed from either face of studs or nailers. Fasteners shall be a minimum of 23/4-inches (70 mm) on center along through the face of either member along the length of studs and from ends of studs, and a maximum of 6-inches (152 mm) on center, minimum 1/2 inch (13 mm) to edges of studs, and minimum 1 inch (25 mm) across studs. Fasteners into nailers from any direction shall be offset vertically a minimum of 23/4 inches (70 mm). Fasteners shall be a minimum 23/4 inches (70 mm) from ends of lumber.
Nail plates shall be spaced such that vertical spacing between plates shall be a maximum of 20 inches (508 mm).
There shall be at least three fasteners through each nail plate into both the primary and retrofit studs.
Fasteners used to secure nail plates to studs shall be a minimum 11/2 inches (38 mm) long and fasteners shall be a minimum of 23/4 inches (70 mm) and a maximum of 6 inches (152 mm) from the ends of retrofit studs.
Fasteners placed in nail plates shall be spaced a minimum of 23/4 inches (70 mm) along the length of lumber and 23/4 inches (70 mm) from ends of lumber.
Fasteners shall be placed a minimum of a 1/2 inch (13 mm) from the edges of the studs and a maximum of 11/2 inches (38 mm) from the abutting vertical edges of primary and retrofit studs.
Staggered fasteners used to secure nail plates shall be spaced horizontally a minimum of 1/2 inches (13 mm).
The broad face of retrofit studs may be reduced in width by methods of cutting, boring, or notching at any number of locations along their length provided that all of the following conditions are met.
The wide face of retrofit studs shall be sized such that the remaining minimum width of the member at each location of reduced width shall not be less than that required by Table 1704.1.
The distance between segments of reduced width shall be a minimum of 8 inches (203 mm) and shall be allowable at the ends of retrofit studs.
The average spacing of fasteners connecting retrofit studs to existing studs shall be maximum 6 inches (152 mm) on center.
The minimum vertical distance between fasteners on studs shall be a minimum of 23/4 inches. (70 mm).
Retrofit studs reduced in width shall not be spliced within 12 inches (304.8 mm) of the location of reduced width. Splice members shall not be notched.
1706.6 Omitted Retrofit Stud — Ladder Assembly
Where existing conditions prevent installation of a full length retrofit stud in accordance with Section 1706.1 or 1707.4, the retrofit stud and its associated two lateral braces shall be permitted to be wholly or partially omitted from that location by installation of a ladder assembly for Retrofit Configurations A and B as defined in Table 1704.1 provided all of the following conditions are met. This method is not allowed for Retrofit Configurations C or D.
No more than two ladder assemblies are permitted on a single gable end.
Where both of the retrofit studs on each side of an omitted retrofit stud would be required by Table 1704.1 to be 2 × 4, they shall both be 2 × 6. Where either retrofit stud on the side of an omitted stud would be required by Table 1704.1 to be 2 × 6, they both shall be 2 × 8. Where either retrofit stud on the side of an omitted stud would be required by Table 1704.1 to be 2 × 8, they both shall be 2 × 10.
Lateral braces adjacent to the omitted lateral brace shall be minimum 2 × 6 lumber extended over four roof framing members and be fastened to each of the four attic-framing members crossed, using minimum four (4) 3-inch long fasteners. Fasteners shall be installed in accordance with Section 1706.4.
Ladder rungs shall be of minimum 2 × 4 lumber installed horizontally with their wide face oriented horizontally and installed to span between the retrofit studs on either side of the omitted retrofit stud. The edge of the ladder rung shall bear against the primary stud at the location of the omitted retrofit stud. Ladder rungs shall be vertically spaced a maximum of 16-inches (406 mm) on center.
Where ladder rungs cross and bear against the primary stud at the location of the omitted retrofit stud, they shall be attached to the primary stud using a stud-to-plate connector with a minimum capacity of 175 pounds (79 kg) in the direction perpendicular to the gable end wall. Ladder rungs shall be attached to the retrofit studs on both sides of the location where the retrofit stud is omitted using two 3-inch long fasteners driven through the retrofit stud and into the end of the ladder rung.
Notching of the ladder rungs shall not be permitted unless the net depth of the ladder rung is a minimum of 31/2 inches (89 mm) in the area of the notch.
1706.7 Interrupted Primary Studs
Where primary studs are interrupted because of existing conditions and where existing conditions permit, a retrofit stud shall be installed that bridges the interruption. It shall be attached to the primary stud both below and above the interruption, sized in accordance with Table 1704.1 for the total length, placed in accordance with Section 1706.3, and attached in accordance with Section 1706.4 along the portion of its length that is in contact with the primary stud.
Retrofit studs shall be permitted to be spliced provided all of the following conditions are met.
Retrofit studs shall be butted to one another at the splice joint and a minimum 4 foot (1219 mm) length of splice member shall be centered at the butt joint.
Lumber splice members shall be nominal 2-inch lumber with the wide face width equal to or wider than the face width of the spliced retrofit studs.
Splice members shall be attached to each of the retrofit stud members on each side of the splice with minimum 7 rows of 3 fasteners for a total of 21 fasteners. Rows of fasteners shall be minimum 23/4 inches (70 mm) from the end of the splice member, minimum 23/4 inches (70 mm) from the splice joint and ends of members, and spaced evenly along the 18-inch (457 mm) splice overlap between these two limits.
Where existing conditions are such that a lateral brace installed in accordance with Section 1707 can only be installed at one end of a primary stud ...
