Code of Massachusetts Regulations › 780 CMR - STATE BOARD OF BUILDING REGULATIONS AND STANDARDS › Chapter 23 - Wood › Section 2304 - GENERAL CONSTRUCTION REQUIREMENTS › Subsection 2304.6 - Wall sheathing

Current through Register 1525, July 5, 2024
Except as provided for in Section 1405 for weatherboarding
				  or where stucco construction that complies with Section 2510 is installed,
				  enclosed buildings shall be sheathed with one of the materials of the nominal
				  thickness specified in Table 2304.6 or any other
approved
material of equivalent strength or durability.
TABLE 2304.6 MINIMUM THICKNESS OF WALL
				  SHEATHING
SHEATHING TYPE
MINIMUM THICKNESS
MAXIMUM WALL STUD SPACING
Wood boards
5/8 inch
24 inches on center
Fiberboard
1/2 inch
16 inches on center
Wood structural panel
In accordance with Tables 2308.9.3(2) and 2308.9.3(3)
-
M-S "Exterior Glue" and M-2 "Exterior Glue"
							 Particleboard
In accordance with Tables 2306.5 and 2308.9.3(4)
-
Gypsum sheathing
1/2 inch
16 inches on center
Gypsum wallboard
1/2 inch
24 inches on center
Reinforced cement mortar
1 inch
24 inches on center
For SI: 1 inch = 25.4 mm.
2304.6.1
Wood structural panel sheathing.
Where wood structural panel sheathing
				is used as the exposed finish on the exterior of outside walls, it shall have
				an exterior exposure durability classification. Where wood structural panel
				sheathing is used elsewhere, but not as the exposed finish, it shall be of a
				type manufactured with exterior glue (Exposure 1 or Exterior). Wood structural
				panel wall sheathing or siding used as structural sheathing shall be capable of
				resisting wind pressures in accordance with Section 1609. Maximum wind speeds
				for wood structural panel sheathing used to resist wind pressures shall be in
				accordance with Table 2304.6.1 for enclosed buildings with a mean roof height
				not greater than 30 feet (9144 mm), an importance factor (
I
)
				of 1.0 and a topographic factor (
K
zt)
				of 1.0.
TABLE 2304.6.1 MAXIMUM BASIC WIND SPEED (mph) (3-SECOND
				  GUST) PERMITTED FOR WOOD STRUCTURAL PANEL WALL SHEATHING USED TO RESIST WIND
				  PRESSURESa, b, c
MINIMUM NAIL
MINIMUM WOOD STRUCTURAL PANEL SPAN
							 RATING
MINIMUM NOMINAL PANEL THICKNESS
							 (inches)
MAXIMUM WALL STUD SPACING
							 (inches)
PANEL NAIL SPACING
MAXIMUM WIND SPEED (mph)
Size
Penetration (inches)
Edges
(inches
							 o.c.)
Field
(inches
							 o.c.)
Wind exposure category
B
C
D
6d common (2.0"* 0.113")
1.5
24/0
3/8
16
6
12
110
90
85
24/16
7/16
16
6
12
110
100
90
6
150
125
110
8d common (2.5"* 0.131")
1.75
24/16
7/16
16
6
12
130
110
105
6
150
125
110
24
6
12
110
90
85
6
110
90
85
For SI: 1 inch = 25.4 mm, 1 mile per hour = 0.447 m/s.
a. Panel strength axis shall be parallel or perpendicular to
							 supports. Three-ply plywood sheathing with studs spaced more than 16 inches on
							 center shall be applied with panel strength axis perpendicular to supports.
b. The table is based on wind pressures acting toward and away
							 from building surfaces in accordance with Section 6.4.2.2 of ASCE 7. Lateral
							 requirements shall be in accordance with Section 2305 or 2308.
c.
							 Wood structural panels with span ratings of wall-16 or wall-24 shall be
							 permitted as an alternative to panels with a 24/0 span rating. Plywood siding
							 rated 16 o.c. or 24 o.c. shall be permitted as an alternative to panels with a
							 24/16 span rating. Wall-16 and plywood siding 16 o.c. shall be used with studs
							 spaced a maximum of 16 inches o.c.
2304.6.2
Interior paneling.
Softwood wood structural panels used for interior paneling shall conform to the
				provisions of Chapter 8 and shall be installed in accordance with Table
				2304.9.1. Panels shall comply with DOC PS 1 or PS 2. Prefinished hardboard
				paneling shall meet the requirements of CPA/ANSI A135.5. Hardwood plywood shall
				conform to HPVA HP-1.