How to Install Stucco

Stucco is a great candidate for the exterior of houses. This works especially greater on humid-climate areas for its breathability. It’s also available for a low cost and is earthquake resistance. 

To help you in installing stucco, follow these steps:

Prepare the wall’s surface

You may use stucco directly over these stiff, strong surface areas, however just if the surface area is approximately textured and also absorbent. If the wall surface does not soak up a sprinkle of water, or if there’s noticeable surface area contamination, clean the surface area thoroughly. If the wall surface is covered in paint or sealant, or if it’s too smooth to sustain stucco, attempt among the complying with therapies: 

  • Acid etching
  • Sandblasting
  • Bush hammer or roughing device (for unpainted, smooth surface areas)
  • Using a bonding agent, referring to particular product instructions. Do not make use of a bonding agent over water-soluble paint
  • If there is any type of uncertainty that the wall surface can support the stucco, use the stucco as you would to a stud wall surface, connecting metal lath and also plastering over it

Damp the surface area

Damp the wall surface right before you use the first coat of plaster, ideally with a fog spray. This enhances the suction bond as well as decreases the amount of water the wall surface soaks up from the plaster, avoiding early drying. The surface area needs to be damp, but not soaked.

  • Postpone the task if the following week of weather entails cold temperature level, heat (over 90 ºF/ 32 ºC), or high wind. These problems will certainly hinder the curing procedure.

Mix the scratch coat 

This coat must be 1-part cement material (consisting of lime) and also 2 1/4 to 4 parts sand. Plastic cement, which has been pre-mixed with lime, is normally the simplest to blend and deal with. Combine this with plaster sand from a completely dry material yard.

  • Just add sufficient water to permit you to trowel the plaster, or it might sag or fall short to stay with the wall surface.

Apply and score the scratch coat

Trowel on a layer 1/4 inch (6.4 mm) thick. Score this with shallow, horizontal lines utilizing a scratched trowel, maintaining the device perpendicular to the wall surface. These grooves will certainly aid the following coat bond onto the surface area.

  • Acid-etched surface areas (among others) might not be fairly rough enough for a solid bond with this approach. Instead, dash on the scratch coat making use of a cement gun, or by whipping it on with a fiber brush or whisk broom. This dislodges air to produce a stronger bond.
  • Some builders integrate the scratch coat and brown coat right into one base coat. If you pick to do this, plan on an overall stucco thickness of regarding ⅜ inch (9.5 mm) for cast concrete, as well as 1/2 inch (127 mm) for system masonry. Allow about 1/4 inch (6.4 mm) of this thickness for the surface layer.

Apply the brown coat after a couple of hrs.

With modern cement on a stiff surface area, there is no need to wait for the scratch coat to cure entirely. For a more powerful bond, trowel on the 2nd, “brown” coat as quickly as the scratch coat is stiff enough to withstand cracking, normally after 4 or 5 hrs. Rod and also float this surface area till it is level and 1/4 inch (6.4 mm) thick.

  • The brown coat mix ought to have 1-part cement materials and also 3 to 5 parts sand.
  • It might help to compact this layer with a shingle float.

Maintain the brown coat moist while it cures

Over the following 48 hrs., it is vital to keep the stucco moist. If the relative humidity of the air is listed below 70%, you will require to mist or fog the surface area one or two times a day. Wait a minimum of 7 days for the brown coat to cure, moistening regularly if it starts to completely dry too soon. Some organizations suggest 10 or perhaps as much as 21 days of drying out for much more crack resistance.

  • In very hot or windy problems, put up a windbreak and also sunshade. You might even need to cover the moistened surface area with polyethylene.

Put on the finish coat

The decorative finish coat consists of 1-part cement materials as well as 1 1/2 to 3 parts sand.[40] Optionally, it may consist of pigment as well to add color. Trowel and drift this on in a thin layer, concerning ⅛ inch (3 mm) thick.[41] Enable it to cure totally before painting (if wanted), complying with the same damp curing instructions above if the weather is hot.

  • If you’re not experienced with applying textured surfaces, a texture roller is a terrific option for attaining high-grade results. Apply the roller uniformly over the last coat.