Appendix BN Extended Plate Wall Construction
Section BN101 General
BN101.1 General.
Detached one- and two-family or townhouse buildings using extended plate wall (EPW) construction shall comply with this code and all of the following:
- 1.
Not more than two stories above grade plane in height.
- 2.
Limited to Seismic Design Categories A and B as determined from Figures R301.2.2.1(1) through (7).
- 3.
Limited to ultimate design wind speeds not more than 115 mph (185 kph) as determined from Figure R301.2(2).
- 4.
Comply with the provisions of Section R602, except as modified by the provisions of this appendix.
Exception: Buildings using EPW construction in accordance with an approved design by a registered design professional.
Section BN102 Construction Requirements
BN102.1 Framing.
The 2 × 6 top and bottom plates and 2 × 4 studs shall be used in accordance with Figures BN102.1(1) and BN102.1(2). A single top plate shall not be permitted. Wall framing shall comply with the requirements for 2 × 4 framing in accordance with Section R602.
BN102.2 Wood structural panel sheathing.
Wood structural panel sheathing with a nominal thickness of 7/16 inch (11 mm) to 1/2 inch (12.7 mm) shall be installed vertically and attached to wall plates and studs in accordance with Figure BN102.1(2) and Table BN102.2. The vertical joints between adjacent wood structural panels shall occur only at framing members. Where used as part of wall bracing, each wood structural panel shall be installed without horizontal joints between the extended top and bottom plates.
MINIMUM NAIL LENGTH AND DIAMETER | MAXIMUM FASTENER SPACING | |
At perimeter of wood structural panels (inches) | In field of wood structural panels (inches) | |
No. 37 power-tool driven common nail (3 1/2″ × 0.131″)a, b, c | 3″ o.c. | 6″ o.c. |
16d box nail (3 1/2″ × 0.135″)a, c | 3″ o.c. | 6″ o.c. |
For SI: 1 inch = 25.4 mm.
- a.
At top and bottom plates where the wood structural panel is in direct contact with the framing, 8d common nail (2 1/2 inches × 0.131 inch) shall be permitted.
- b.
Full round head nail with minimum head diameter of 0.281 inch (7 mm).
- c.
Nails are in accordance with ASTM F1667.
BN102.3 Wall bracing.
Wall bracing for EPW construction shall comply with the requirements for WSP or CS-WSP or CS-G bracing methods in Section R602.10, except that the sheathing fasteners shall comply with Table BN102.2.
BN102.4 Rim joists.
Rim joists supporting an EPW shall comply with Figure BN102.4(1) or BN102.4(2). Sawn 2× lumber or engineered wood rim board shall be used to construct rim (band) joists. Engineered wood rim board shall comply with Section R602.1.7. The minimum bearing length requirements for the floor joists shall be satisfied or joists shall be supported with metal hangers.
For SI: 1 inch = 25.4 mm.
For SI: 1 inch = 25.4 mm.
BN102.5 Foam plastic insulating sheathing.
Foam plastic insulating sheathing with a total thickness of 2 inches (51 mm) shall be installed directly to the exterior surface of the 2 × 4 studs between top and bottom plates and flush with the 2 × 6 top and bottom plates as shown in Figure BN102.1(1). The foam plastic insulating sheathing shall comply with ASTM C578 or ASTM C1289 with a minimum compressive strength of 15 psi and shall be permitted to be installed in one or more layers.
BN102.7 Uplift connections.
Where roof uplift tie-downs are required in accordance with Section R802.11, the roof tie-downs shall be fastened to either side of the double top plate or, where required to be fastened to studs, shall be installed on the interior face of the EPW in accordance with the manufacturer’s installation instructions. Where uplift forces determined in accordance with Section R602.3.5 require approved uplift connectors between floors or between the foundation and the floor, these uplift connectors shall not rely on wood structural panel sheathing for resisting the wind uplift forces.