Fiberboard Sheathing

Help build strong, energy-efficient walls, economically

Provides Corner Bracing

No supplementary corner bracing is required by the model building codes when structural grade fiberboard sheathing panels, 1/2" or 25/32", are applied vertically or horizontally.

Ideal for Any Siding

Fiberboard sheathing is easy and economical to install with hardboard, wood, or any other siding material. And, there is no fear of crushing when staples or nails are driven securely.


Fiberboard sheathing withstands the wear and tear involved in handling prefabricated wall sections. And, because it doesn't break easily, there is less waste. Fiberboard sheathing is not adversely affected by inclement weather or sunlight.


Fiberboard sheathing's insulating properties help save energy and money.

Reduces Noise

Fiberboard offers more sound transmission resistance than most sheathing materials. When used with sound-deadening board and gypsum wallboard, outside walls become excellent sound barriers against outdoor noise.

Controls Vapors

Fiberboard sheathing is water repellent, forms a weather-tight cover for walls, and eliminates the need for building paper with most sidings. Fiberboard sheathing's high permeance also permits unwanted vapor to escape outward through sidewalls - one of the few sheathing products available with this permeance advantage.

Applies Easily

Fiberboard sheathing offers rapid and efficient applications with nails or staples.

Installation Instructions

Structural Sheathing, 1/2" regular and 1/2" and 25/32", can provide racking strength when applied over studs 16" O.c., and nailed as described in the application portion of these instructions. However, specific racking resistance requirements will be determined by local building codes. Consult your local building code for building paper and vapor retarder requirements.


Regular sheathing is available in nominal 1/2" x 4' x 8', 4' x 9', and 4' x 10' square edge sheets. Structural sheathing is available in nominal 1/2" and 25/32" thickness and 4' x 8' and 4' x 9' square edge.

Product Standards

Applicable product standards are ASTM C208 or CAN/ULC-S706.


Sheathing should be applied vertically with the long edges parallel to the vertical studs. Center all joints over the framing members with a 1/8" gap between edges. Leave a 1/2" gap at the doors and windows. Sheathing should extend from sill to top plate. If not, headers for adequate nailing should be provided at all horizontal joints. Horizontal application is allowed if blocking is provided at all horizontal joints. See ASTM C846 for complete details.


Table 1

Vapor Permeance
1/2" Regular 1.32 5.0 ave. min.
1/2" Structural 1.22 5.0 ave. min.
25/32" Structural 2.06 5.0 ave. min.
*The higher the R-value, the greater the insulating power.

Table 2   For non-structural applications, the following fastening chart should be used.


Fastener Size
Edges                  Field
1/2" Regular 1-3/4" nail ** 6" 12"
1/2" Structural 1-3/4" nail ** 6" 12"
25/32" Structural 2" nail ** 6" 12"
**See local building code. Staples may be used in lieu of nails.

Table 3   For structural applications, use the following fastening chart to take advantage of shear values for sheathing.
Allowable Working Shear Stress for Wind or Seismic Forces on Vertical Shear Walls with Fiberboard Sheathing 1,2,3,4,5

Thickness & Grade

Fastener Type
Shear Stress (plf of wall)
Perimeter Spacing4
2"          3"        4"
1/2" Regular Consult Sheathing Manufacturer Consult Sheathing Manufacturer
1/2" Structural 8d common nail or 11 ga.
galv. roofing nail, 1-1/2" long, 7/16" head
260 230 170
  7/16" crown, 16 ga. galv. staple, 1-1/8" leg 225 200 150
  1" crown, 16 ga. galv. staple, 1-1/8" leg 340 300 230
25/32" Structural 8d common nail or 11 ga.
galv. roofing nail, 1-3/4" long, 7/16" head
270 240 180
  7/16" crown, 16 ga. galv. staple, 1-1/2" leg 220 200 150
  1" crown, 16 ga. galv. staple, 1-1/2" leg 325 290 220
1. All panel edges shall be backed with 2" or wider framing of Douglas Fir, Larch or Southern Pine. 2. Fiberboard sheathing diaphragms shall not be used to brace concrete or masonry walls. 3. Fiberboard sheathing on one side only. 4. Fasteners spaced every 6" in the field. 5. Safety factor used was 2.8.


Cyclical Testing of Fiberboard Shear Walls Final Report |  DOWNLOAD PDF
Support Documents for changes to the 2006 IBC Code For S84 Cyclical Testing of Fiberboard Shear Walls Final Report.pdf Cyclical Testing of Fiberboard Shear Walls with Varying Aspect Ratios NAHB-RC (ASTM 2126) This report compares cyclical shear values for fiberboard shearwalls with aspect ratios from 1 to 1 through 4 to 1 and was used to support a change to an aspect ratio of 3 to 1 for Fiberboard. .

NAFA Report 9660 |  DOWNLOAD PDF
Support Documents for changes to the 2006 IBC Code For S117 NAFA Report 9660.pdf PFS Test Report #96-60 Racking Loads for Fiberboard (ASTM E72) This report is the basis for the monotonic shear values published by the North American Fiberboard Association since 1997. These values were proposed for the Working Draft of the IBC and denied due to lack of cyclical data.

Dolan Report WMEL 2002-03 |  DOWNLOAD PDF
Support Documents for changes to the 2006 IBC Code, Monotonic and Cyclic Tests of Shear Walls with Gypsum Wallboard, Fiberboard, and Hardboard Sheathing Report No. WMEL-2002-03 J.D. Dolan and Adam Toothman This report provides cyclical data which supports the monotonic values from Report 96-60.