What is code for exterior wall sheathing?

1304.13 EXTERIOR WALL SHEATHING. (a) Wooden structural sheathing panels shall be installed on all exterior frame walls.

What size sheathing is used for exterior walls?

For covering existing siding, 1/2-inch and 3/4-inch thicknesses are commonly used. Standard panels are 2 by 8, 4 by 8, and 4 by 9 feet, although some can be purchased in fan-folded panels that run up to 50 feet long.

What size OSB should be on exterior wall?

Exterior walls

Minimum thickness of wall sheathing for use on walls; 3/8" plywood or 5/16" OSB. If you use fibre cement siding, go with 1/2" plywood or 7/16" OSB for the exterior walls.

Do exterior walls need sheathing?

Wood frame exterior walls must be fully sheathed, including areas above or below wall openings, with minimum 7/16-in. wood structural panels. Interior shear walls must be fully sheathed including areas above or below wall openings with minimum 7/16-in. wood structural panels on both wall faces.

How thick should exterior plywood sheathing be?

The International Residential Code specifies 3/8-inch plywood for sheathing walls with a standard stud spacing of 16 inches, if the siding is nailed to the studs through the sheathing. If the nails penetrate the sheathing, but not the studs, the minimum plywood thickness that the IRC designates is 1/2 inch.

How to Install OSB Wall Sheathing or Panels

Can you use 3/8 plywood wall sheathing?

The International Residential Code specifies 3/8-inch plywood for sheathing walls with a standard stud spacing of 16 inches, if the siding is nailed to the studs through the sheathing. If the nails penetrate the sheathing, but not the studs, the minimum plywood thickness that the IRC designates is 1/2 inch.

What is the best plywood for exterior walls?

3. Structural Fiberboard. Plywood and OSB are largely considered the best wall sheathing choices because of their overall abilities to hold fasteners well, create a strong bond between studs, and provide some thermal advantages.

Is plywood or OSB better for sheathing?

Industry voices from panel manufacturers or their main trade group—APA – The Engineered Wood Association—say that there's no real difference between the two panels: OSB's and plywood's structural characteristics are equivalent, and they can be used interchangeably.

How thick should wall sheathing be?

The U.S. Department of Energy has determined that 7/16-inch sheathing is the minimum appropriate thickness for structural wall sheathing with an exception for gable end walls, where the minimum thickness is 3/8 inch.

Does sheathing have to end on a stud?

Securing the sheathing to the frame

Important, DO NOT fasten the four corners first. To secure the panel to the stud, start at the top left corner of the panel and fasten the panel to the vertical side stud from top to bottom.

Can OSB be used for exterior walls?

Install OSB at least 6 inches off the ground to prevent moisture issues from splashing rainwater. OSB is available with a tongue and grove finish; these boards are made to fit together like a puzzle and increase the strength of the exterior finish.

How far down should sheathing go?

The wall sheathing should extend below the rim joist, which is inset on this house to allow for a continuous band of insulation. The wall sheathing below dictates the overhang. It's about 9 inches in this case, and Ben subtracts a quarter inch to allow for inconsistencies.

Should OSB be installed vertically or horizontally?

After much research on the matter – as it impacts tiny houses – I've landed on a rule-of-thumb to follow: If the height of a wall is less than 8-feet, install the plywood (or OSB) vertically. If the height of a wall is greater then 8-feet, install the plywood (or OSB) horizontally.

What is best for exterior walls?

What can I use instead of OSB?

In addition to OSB, builders can choose plywood, fiberboard, rigid foam, diagonal boards, and fiberglass-faced gypsum panels. If you're a dyed-in-the-wool OSB user, it might be time to consider some of the available alternatives to OSB.

How thick are residential exterior walls?

However, the standard thickness of ICF exterior walls is 12 inches, reducing room sizes and minimizing the home's square footage. To maintain the original square footage of a building plan, you must increase the overall dimensions of the house, which also impacts the design of the roof and foundation.

How thick should outside walls be?

External walls are generally 10 to 12 inches wide. Homes that are built with rammed earth or heavy exterior masonry will have thicker walls. There is no limit to how thick an exterior wall can be.

What is used for exterior sheathing?

There are many exterior wall sheathing options available, with wood sheathing being one of the most commonly used materials. Wood sheathing materials include plywood, oriented strand board (OSB), and waferboard. Plywood is made of whole sheets of wood that are cross-laminated.

What is better CDX or OSB?

Although some people will ultimately choose CDX, many experts argue that OSB is better overall for roofing. OSB is far less likely to expand and contract when exposed to humidity and moisture, even though it will take longer to dry. With wrapping, though, it can withstand the elements without issue.

What does CDX stand for?

The letter “X” in CDX refers to the type of glue used in the factory to bond the plywood veneers. Some mistakenly think the “X” stands for “exterior”—which is not true. The letter “X” stands for exposure, which means the plywood is tough enough to withstand a little moisture—but for only a short time.

What type of plywood can be used outside?

CDX is the most common exterior plywood grade. It comes in 3/4-, 5/8- and 1/2-inch thicknesses. Appearance stamps on plywood range from cabinet-grade (A) to construction grade (C and D). Exterior plywood carries an X stamp, which identifies it as suitable for use outdoors.

Is OSB good for sheathing?

OSB is now used for about 70 percent of all floor, wall and roof sheathing in North America. Building codes, the Engineered Wood Association, architects and most builders rate plywood and oriented strand board (OBS sheathing) equal in strength and durability.

Is CDX plywood exterior grade?

CDX plywood is an exterior grade plywood only in the sense of considering the adhesive used for connecting the veneer plys. The wood isn't pressure treated or treated in any other way to make it waterproof, unless it is marked as being “pressure treated” plywood.