How To Assemble Treated Plywood Sheathing Outside?

Structural exterior wall sheathing is a crucial part of a building’s wall system, tying framing studs together to strengthen the wall system. It is typically installed horizontally and secured to the slab, plumbed, and braced. The proper way to install exterior OSB wall sheathing depends on the specific needs of the structure. For example, horizontal sheathing can be installed horizontally and a 16 penny nail can be used between the sheets to ensure expansion and reduce moisture swelling.

Exterior wall sheathing strengthens the wall system, provides a nailing base for siding, and provides protection against outside elements. It can be either structural or non-structural. To install exterior wood siding, gather materials and make a plan, remove existing cladding, and allow the sheets to extend over door and window openings.

IAQ concerns may arise with pressure treated plywood for the bottom sheathing course. Apply primer or sealant to the old plywood to create a good bonding surface, then use construction adhesive and screws to attach the new sheathing. Secure the sheathing to the frame with 2 ½ inch 8p ring nails or manufacturer’s recommended fasteners every 6 inches. Nail each panel of sheathing into place by driving one 8d nail every 6-inches along the seams and wherever a stud is behind its plane.

In summary, installing exterior wall sheathing is a crucial step in building a house, providing a secure and weather-resistant structure.

How do you fasten exterior sheathing?

Secure the sheathing with 2 ½ inch 8p ring nails every 6 inches, starting at the top left corner and fastening it to the vertical side stud from top to bottom. Fasten the top part to the top horizontal stud until it reaches the vertical stud adjacent to the vertical side stud. Fasten the bottom part to the bottom horizontal stud until it reaches the vertical stud adjacent to the vertical side stud. Fasten the panel to the first vertical inner stud, moving from top to bottom. Repeat steps until the panel is secure along all studs of the frame.

Cut holes into the sheathing for windows and doors by drilling a 1/2-inch wide hole into each corner of the door and window frames. Wear goggles and cut the sheathing along the edge of the frame with a reciprocating saw. Saw through the sheathing until all four sides are cut. When cutting a door hole, instruct a fellow worker to hold the sheathing inside the door frame to prevent it from falling or tearing away from the wall frame.

Is pressure treated plywood the same as exterior plywood?

Exterior plywood is a versatile material used for various purposes, including construction, cost, and aesthetics. It comes in various types, such as pressure treated plywood, overlaid plywood, oriented strand board (OSB), and T1-11. Pressure treated plywood is infused with chemicals to enhance its resistance against mold and mildew. Overlaid plywood has a cleaner finish and better resistance to wear and tear. OSB is an engineered substitute for semi-exposed areas, while T1-11 is commonly used for siding.

The main differences between exterior plywood types are construction and cost. Marine plywood is the most expensive due to its appearance and construction, while CDX is the least expensive but better suited for projects covered in siding. ACX is a middle ground, less expensive but more attractive than CDX. Each type of exterior plywood has different thickness and weight, which affects its use and durability. Marine plywood is the heaviest, ideal for bench durability but may buckle under weight when used as shelving or siding.

How thick should exterior plywood sheathing be?

In the context of residential construction, the use of a rated sheathing panel, such as oriented strand board (OSB) or plywood, with a thickness of 0. 95 cm (or 3/8 in), is a standard practice. This sheathing is comparable to that used for shear wall sections. Nevertheless, it is customary to utilise sheathing thicknesses that exceed the prescribed minimums, a practice colloquially termed as “over-sheathing.”

Which way do you run plywood sheathing?

The “strength axis” stamp on APA rated sheathing indicates the direction of the board with the most strength. When installing subfloor and roofing, panels must be installed with the strength axis perpendicular to the supports. When installing walls, the strength axis can run either vertically or horizontally to supports. Most 4×8 OSB panels have nailing lines running both directions on the panel, while 4×9 and larger panels have them running parallel with the long edge.

High winds may require sheathing to be run horizontally to stiffen the wall assembly. Stud spacing can also be reduced to meet loads, with balloon framed walls often calling for LVL or LSL studs instead. Thor Matteson in his book Wood-Framed Shear Wall Construction suggests that staggered panel joints will deform about 25 less than walls with all joints lined up.

What is the minimum gap dimension between exterior plywood sheathing?

The American Society of Appraisers (APA) recommends a 1/8-inch space between panel edge and end joints for plywood and oriented strand board (OSB) to minimize expansion and buckling, which can lead to costly and time-consuming callbacks. To ensure best performance, follow these panel spacing and nailing recommendations for APA Rated Sheathing, APA Rated Sturd-I-Floor®, and APA Rated Siding. Spacer-type panel edge clips may be used for roof sheathing applications.

Panel spacing is not a requirement, and some manufacturers may require a space during installation. Panel buckling may be an aesthetic or serviceability issue, not a structural deficiency. Gaps initially present may have closed due to normal moisture-related expansion. If the flatness of sheathing or flooring panels is acceptable, APA generally recommends installing finish flooring, siding, or roofing as planned, regardless of gaps present.

Should exterior sheathing be installed vertically or horizontally?

Structural sheathing panels have a “strength axis” that runs parallel to the panel’s length, and are installed perpendicular to supports on roofs and floors to create the strongest roof or floor. Horizontal sheathing is better at resisting wind pressure, as shown in the American Wood Council’s Wood Frame Construction Manual (WFCM). Horizontal sheathing outperforms vertical sheathing, especially at higher wind speeds.

For instance, a 3/8-in.-thick panel with a span rating of 24/0 can handle three-second gusts up to 195 mph when installed horizontally on studs spaced 24 in. on center, while vertically, it can only handle gusts up to 110 mph on the same stud spacing.

The International Code of Practice (IRC) allows for the orientation of sheathing for wind loads, but it requires the panels to be installed perpendicular to supports when using 3-ply plywood panels on studs spaced greater than 16 in. on center. The grain of the face plies is typically oriented with the long axis of the panel, and the single alternate ply in the middle doesn’t provide enough strength for wind pressure when installed vertically.

In coastal areas of the southeast, where hurricanes are common, the IRC points builders to the WFCM and other resources for guidance.

Do you nail or screw exterior sheathing?

Exterior Jobs Nails are a popular choice for roofing, siding, and sheathing projects due to their lower price point and the need for fasteners. However, there are better times to use nails vs. screws. Historically, nails were chosen over screws due to their quicker fastening in place. Advancements in tool technology, such as electric and pneumatic screwdrivers, led to an increase in the popularity of screws.

The cordless drill/driver, the most popular portable power tool ever invented, also played a significant role in the popularity of power-driving screws. Both nails and screws have their advantages and disadvantages in various applications and situations.

What is the nailing pattern for exterior sheathing?

The most commonly utilized nails are those of 16 gauge, otherwise known as “common nails.” The staples are 5 inches in length and are spaced a maximum of 3 inches along the edge and 6 inches in the material’s field. The aforementioned staples are positioned at a distance of six inches along the edges and twelve inches within the material’s field.

How far apart should screws be for exterior sheathing?

The fasteners utilized are 5/8″ staples or 1 5/8″ type W or S screws, with a maximum spacing of 4″ along the edges and 8″ within the material’s field.

What should never be done with pressure treated wood?

Pressure-treated wood should not be used for food containers or cutting boards, and even playsets should be protected with a sealant. Workers should wear gloves, protective clothing, respirators, and goggles when working with pressure-treated wood. Wash clothes exposed to treated lumber separately and avoid burning it. Applying an oil-based primer and protective sealant can limit pesticide exposure from skin contact, dust, or rain, using sealants labeled as safe for pressure-treated lumber.

Should exterior sheathing be nailed or screwed?

Exterior Jobs Nails are a popular choice for roofing, siding, and sheathing projects due to their lower price point and the need for fasteners. However, there are better times to use nails vs. screws. Historically, nails were chosen over screws due to their quicker fastening in place. Advancements in tool technology, such as electric and pneumatic screwdrivers, led to an increase in the popularity of screws.

The cordless drill/driver, the most popular portable power tool ever invented, also played a significant role in the popularity of power-driving screws. Both nails and screws have their advantages and disadvantages in various applications and situations.