Stucco thickness depends on the backup system and on whether or not lath is present. The additional thickness of stucco on metal base is required to attain the desired hardened cementations properties. Attach the masonry ties securely through the panels and into the steel or wood framing. A 3.2 mm (1/8 in) thick polyethylene spacer. 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. Generally, stucco that is applied directly to solid surfaces is placed in two coats that together total 5/8 inch of thickness. 2. Depending upon your particular climate, expansion and contraction of fiber cement product should be considered. 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. These days, it makes more sense to start with wall sheathing: rigid foam, diagonal boards, or plywood. Secure stucco mesh to your walls and then apply your layers of stucco for a watertight finish. Space the ties as required by masonry courses. Always refer to the fire-rated assembly test before making an assumption. 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). Asphalt felt, then metal lath, then stucco -- that was all. Install casing bead as a plaster stop at the corners of doors … The minimum thickness over framed walls is 3/4-inch. Mix the stucco until it forms the consistency of thick mud. As far as painting, it is not done on new stucco as the color is in the finish. 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. Trowel the 1/8" thick finish coat over the brown coat, starting at the bottom and working to the top of the wall. The siding is 20 years old and we want to get rid of it. thick. 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. Finish Coat Stucco applied to a 1/8" thickness. Place stucco wheelbarrow for each application. I have plywood siding with vertical battens attached to make it look like board & batten. As an insulated stucco assembly, LaHabra Fastwall 100-HE provides a durable exterior with an energy saving layer of continuous insulation. Kraft paper is factory applied to prevent over spray of stucco. For many decades in California, stucco was installed directly over the studs, without any sheathing whatsoever. (stucco) as an exterior finish over plywood wall sheathing is recognized as a “generic” construction system under provisions in the Uniform Building Code (UBC). Make sure to have each joint supported a 2" x 4" wood, with or without plywood backer. However, on metal base the thickness is 5/8 to 7/8 inch. The scratch coat must be scored horizontally on vertical surfaces. It must be solid enough to hold in the lath, but fluid enough to spread easily. Buy a prepared brown coat stucco mix and add water according to package directions. .. Pros. In ASTM C926, the Standard Specification for Application of Portland Cement-Based Plaster, thicknesses are provided for scratch, brown, and finish coats. optional when installed over Tyvek® StuccoWrap™. treated plywood residential EIFS system 1 (optional when Zenith™ is installed over Tyvek®. It is our opinion that major cause for cracked stucco is improper plywood installation during stucco installation process. How do you stucco over plywood? Method 1 of 2: 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. Depending on the contamination, you might only need to wash with water. Fastwall 100-HE is a "High Efficency" Continuous Insulation (CI) stucco assembly with a base thickness between 3/8 to 1/2 in. 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. Our Drainage Mat. Plywood is a dimensionally stable wood, so it resists major expansion, contraction, warping, and swelling. Note the continuity of the thermal control layer via overlapping foam layers at the slab-to-wall interface. See stucco to fill the gaps in the mesh and apply to a thickness of about 3/8 of an inch thick. Professional stucco repair contractor can always recognize stucco cracking originated by plywood because of the different crack directions. CA has a high humidity level and much more rain. Conventional stucco over wood should always be applied as a three-coat system. 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. It can be applied with either a one coat or three coat process, but there is some confusion about the methods. Manufactured stone veneer is a version of hardcoat stucco where the top coat is replaced with an embedded thin stone veneer ( Photograph 3 ). 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. For example, one coat stucco is actually a two-step process. UBC provisions specify 7/8-inch exterior cement plaster over plywood wall sheathing, with 2x wood studs … Simply screw the plywood over the entire window or use clips to install the plywood inside the window frame. Apply two layers of grade D building paper or asphalt felt to the plywood siding. 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. Step 3: Install Galvanized Lath or Netting. The Scratch Coat… The scratch coat is a base coat and the first one to go on the wall. Plywood siding is available in large sheets of 8 feet long or longer, so installation goes faster. One-coat systems may be applied as thin as 3/8-inch. 1. Lets take a look at each technique as well as the advantage that each has to offer. that stucco cladding be installed in three coats with a total thickness of 21 mm. The thickness of stucco on a solid substrate is 5/8 or 1/2 inch. that includes a layer of continuous insulation up to 1-1/2 in. The big advantage to three coat is its strength and durability. 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. Steps. Local codes do not dictate how the stucco is applied or how far it needs to be above the surface of the ground. Stucco cracks develop for quite a few reasons, as we mentioned above. Fasten the netting to the wall, using galvanized nails or … Allow this base material to harden for one hour and scratch lightly with a … 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. 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. This construction, which uses 2x wood studs spaced 16 inches o.c., eliminates the need for a Spread the stucco over the wall with the help of smooth trowel. Spray Lath is a West Coast product, where stucco is spray applied to the surface of the lath to build up the stucco thickness. The thinner finish weighs from 5 to 6 pounds per square foot, compared to 9 pounds for three-coat, and it is cost-competitive with traditional stucco. My only warning using this product is properly hiding the seams (where two or more edges of Hardie panel meet or join. Zenith Spacer. Then feel free to install vertical strapping and stucco. Stucco works different in different climates. What is the correct thickness of stucco? Since it is twice as thick as one co… Although I do agree that six inches at least be done. Sometimes caulk or stucco patch can be used to hide the joints. Successive coats should be applied as soon as possible after the Scratch coat =3/8 inch thick, brown coat =3/8 inch thick, and finish coat =1/8 inch thick. Fortunately, whether your house has vinyl, brick, or stucco siding, the process of installing plywood over the windows is relatively straightforward. A white, 3.2 mm (1/8 in) thick mat composed of open weave polymer threads. 1. Install weep screeds and casing bead. Do The Job Right Proper installation is important if these desirable results are to be ... (stucco exterior finish) over plywood wall sheathing. Adequate protection of the plywood may be accomplished upon application of one layer of Grade B building paper applied over the plywood. You can use caulk or stucco patch, or epoxy on the joints. If water sprinkled on the wall is not readily absorbed, then the surface must be handled differently. 2. It is applied … Let dry for 24 hours. 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