Spray Lath is a West Coast product, where stucco is spray applied to the surface of the lath to build up the stucco thickness. Always refer to the fire-rated assembly test before making an assumption. Fortunately, whether your house has vinyl, brick, or stucco siding, the process of installing plywood over the windows is relatively straightforward. UBC provisions specify 7/8-inch exterior cement plaster over plywood wall sheathing, with 2x wood studs … Before applying stucco over wood, you will need to attach a layer of roofing felt to the surface followed by a sheet of wire mesh.Then apply a thin layer of stucco to the wire mesh surface as a base for the final coat. While there are several parts of the North America where stucco always has a strong presence, there appears to be a general renewed interest in portland cement plaster for building finishes everywhere. It is our opinion that major cause for cracked stucco is improper plywood installation during stucco installation process. 1. Install casing bead as a plaster stop at the corners of doors … Stucco thickness depends on the backup system and on whether or not lath is present. Finish Coat Stucco applied to a 1/8" thickness. Local codes do not dictate how the stucco is applied or how far it needs to be above the surface of the ground. Attach the masonry ties securely through the panels and into the steel or wood framing. Buy a prepared brown coat stucco mix and add water according to package directions. Steps. Spread a 3/8-inch thick layer of base or scratch coat stucco over metal lath with a rectangular mason's trowel and roughen the surface with the notched edge of the trowel. However, on metal base the thickness is 5/8 to 7/8 inch. The minimum thickness over framed walls is 3/4-inch. Follow with the three-dimensional drainage mat and two more layers of paper or felt. A 3.2 mm (1/8 in) thick polyethylene spacer. Apply two layers of grade D building paper or asphalt felt to the plywood siding. Step 3: Install Galvanized Lath or Netting. Let dry for 24 hours. Trowel the 1/8" thick finish coat over the brown coat, starting at the bottom and working to the top of the wall. .. Spread the stucco over the wall with the help of smooth trowel. that includes a layer of continuous insulation up to 1-1/2 in. J. Plywood Siding K. Vinyl Siding L. Fiber Cement Siding M. Metal Siding Brick Cavity Wall Masonry or stone veneer can be applied over DensGlass Sheathing just as it would be over any other type of sheathing. (stucco) as an exterior finish over plywood wall sheathing is recognized as a “generic” construction system under provisions in the Uniform Building Code (UBC). Since it is twice as thick as one co… Depending upon your particular climate, expansion and contraction of fiber cement product should be considered. Successive coats should be applied as soon as possible after the CA has a high humidity level and much more rain. These days, it makes more sense to start with wall sheathing: rigid foam, diagonal boards, or plywood. Make sure to have each joint supported a 2" x 4" wood, with or without plywood backer. Do The Job Right Proper installation is important if these desirable results are to be ... (stucco exterior finish) over plywood wall sheathing. Check out our recommended tools right here: https://www.stuccoplastering.com/tools/ Hello, our faithful subscribers and plasterers around the world! treated plywood residential EIFS system 1 (optional when Zenith™ is installed over Tyvek®. Figure 2 - Stucco is installed over rigid insulation, which is installed over a drainage plane consisting of a drainage gap and building wrap layer over the sheathing. Fasten the netting to the wall, using galvanized nails or … The thickness of stucco on a solid substrate is 5/8 or 1/2 inch. The spaces between the strips of Kraft paper allow for the visual alignment of the sheet for mechanical attachment of the ribs to the substrate. Install weep screeds and casing bead. uniform thickness of stucco finish and reduces the risk of wavy wall surfaces. All these systems apply a single base coat and a top coat with a total thickness of 2/8 to 1/2-inch, compared to 7/8 to 1 inch for traditional three-coat stucco. Place stucco wheelbarrow for each application. Manufactured stone veneer is a version of hardcoat stucco where the top coat is replaced with an embedded thin stone veneer ( Photograph 3 ). How do you stucco over plywood? Fastwall 100-HE is a "High Efficency" Continuous Insulation (CI) stucco assembly with a base thickness between 3/8 to 1/2 in. Adequate protection of the plywood may be accomplished upon application of one layer of Grade B building paper applied over the plywood. optional when installed over Tyvek® StuccoWrap™. Secure stucco mesh to your walls and then apply your layers of stucco for a watertight finish. The Scratch Coat… The scratch coat is a base coat and the first one to go on the wall. Sometimes caulk or stucco patch can be used to hide the joints. As far as painting, it is not done on new stucco as the color is in the finish. For example, one coat stucco is actually a two-step process. A white, 3.2 mm (1/8 in) thick mat composed of open weave polymer threads. For many decades in California, stucco was installed directly over the studs, without any sheathing whatsoever. My only warning using this product is properly hiding the seams (where two or more edges of Hardie panel meet or join. The additional thickness of stucco on metal base is required to attain the desired hardened cementations properties. You can use caulk or stucco patch, or epoxy on the joints. Hardcoat stucco is typically a three layer cementitious rendering (scratch coat, brown coat and top coat) applied over a building paper, metal lath and sheathing (Photograph 2). 2. Use a trowel to dance stucco. Rather than using drywall on the ceiling, stucco installations that go beyond the basic troweled-on layer need plywood backing to hold the metal lath in place. Professional stucco repair contractor can always recognize stucco cracking originated by plywood because of the different crack directions. Then feel free to install vertical strapping and stucco. Plywood siding is available in large sheets of 8 feet long or longer, so installation goes faster. Simply screw the plywood over the entire window or use clips to install the plywood inside the window frame. Zenith Spacer. Depending on the contamination, you might only need to wash with water. If water sprinkled on the wall is not readily absorbed, then the surface must be handled differently. 2. Pros. Stucco provides a durable, low maintenance finish that adds lots of character to a house. This construction, which uses 2x wood studs spaced 16 inches o.c., eliminates the need for a Plywood is a dimensionally stable wood, so it resists major expansion, contraction, warping, and swelling. It must be solid enough to hold in the lath, but fluid enough to spread easily. What is the correct thickness of stucco? Kraft paper is factory applied to prevent over spray of stucco. Asphalt felt, then metal lath, then stucco -- that was all. Scratch coat =3/8 inch thick, brown coat =3/8 inch thick, and finish coat =1/8 inch thick. Stucco works different in different climates. The Alberta Building Code (ABC), which is the legislated building code in Alberta, is based on the NBC but also permits two-coat stucco with a total thickness of not less th an 19 mm. It is applied … Our Drainage Mat. See stucco to fill the gaps in the mesh and apply to a thickness of about 3/8 of an inch thick. The siding is 20 years old and we want to get rid of it. One-coat systems may be applied as thin as 3/8-inch. The layer of Grade B paper may be applied as aWhen plywood ex-separate sheet or attached to and a part of paperback stucco mesh. Although I do agree that six inches at least be done. For example, three sides of the house might be plywood, with the front being made of manufactured veneer stone or cedar shingles. thick. The big advantage to three coat is its strength and durability. We are often asked if stucco and plaster are the same thing, and if plaster and exterior insulation finishing systems (EIFS)are the same thing. 1. Generally, stucco that is applied directly to solid surfaces is placed in two coats that together total 5/8 inch of thickness. Note the continuity of the thermal control layer via overlapping foam layers at the slab-to-wall interface. As an insulated stucco assembly, LaHabra Fastwall 100-HE provides a durable exterior with an energy saving layer of continuous insulation. I have plywood siding with vertical battens attached to make it look like board & batten. Lets take a look at each technique as well as the advantage that each has to offer. Conventional stucco over wood should always be applied as a three-coat system. As with the brown coat, mix only enough stucco that can be applied in 1 hour and complete the entire wall or major section in one session to reduce possible color variations. In ASTM C926, the Standard Specification for Application of Portland Cement-Based Plaster, thicknesses are provided for scratch, brown, and finish coats. that stucco cladding be installed in three coats with a total thickness of 21 mm. Mix the stucco until it forms the consistency of thick mud. 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