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.
- There shall be at least two retrofit studs and lateral brace assemblies on each side of the location where a retrofit stud is omitted.
- 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.