What is Stucco?
Stucco is cement plaster applied either to the indoor or outdoor surfaces of buildings. Stucco is hard and durable. It’s also rot and fungus resistant. It’s a great low-cost home exterior material. It does not require a lot of maintenance. The stucco is a plaster type material that is made from cement, sand, and lime. Stucco provides a hard, reliable, durable and low-cost surface that requires little maintenance and can be used to obtain different textures and finishes. Stucco might be applied over metal lath, a galvanized wire mesh used that must be covered that needs to be covered protecting it against rust.
The Advantages of Stucco
Stucco is a low-cost, strong, and durable finish. It can be used in a wide variety of climates. It is versatile and can be applied to concrete, concrete masonry, brick, wood frame, or steel frame. It is fire resistant and colour retentive. Thus, various pigments can be added to the plaster to give your stucco exactly the appearance that you are looking for.
The purpose of the metal lath allows the stucco to adhere to become stronger.
How Many Coats of Stucco Are Needed
The stucco must be applied over lath to keep it away from the frame sheathing by about one-quarter of an inch. Stucco must be applied using thin coats, the first one must be forced into the lath so the mesh is entirely embedded within the stucco mix. It is recommended to apply stucco in three different coats, adding over one inch of stucco surface once the plaster has been applied. A 3-coat stucco system consists of a scratch coat, brown coat, and finish coat. The scratch coat is applied first to provide a strong base for the system. It’s embedded in metal lath, which strengthens and secures the coat. The brown coat is applied next to create an even surface for the finish coat. The finish coat is applied last, creating the decorative finish on the wall surface.
Building Codes Standards on Stucco
One of the major secrets to applying stucco is mixing stucco so every batch has the same perfect consistency The International Building Code (IBC) provides rules for the minimum time delay between each coat of plaster.
The two standards from the ASTM that regulate the application of stucco are:
ASTM C 926 Standard specification for application of Portland Cement-based plaster
ASTM C 1063 Standard specification for installation of lathing and furring to receive interior and exterior Portland Cement-based plaster.
Pre-Mixed or On-Site Mixed Stucco
Stucco is mixed on site and applied in various layers of the walls.
Commercially prepared stucco mixes can be an easy solution on your construction project.
One of the major secrets to applying stucco is mixing stucco so every batch has the same perfect consistency. However, stucco can also be mixed by you using:
Three parts sand
One part Portland cement
Hydrated lime to ten percent of the cement by the volume.
Mixing stucco is commonly on a one cubic foot basis, mixing Portland cement, blended hydraulic cement, masonry cement, plastic cement, hydrated lime and fly ash, three cubic feet of plaster sand (coarser than masonry sand), and from four to seven gallons of water. The formula used to create the stucco will determine if admixtures are needed.
The slower the stucco dries the stronger it will become. In sunny and hot locations stucco must be shaded to prevent the dehydration of the stucco mix. If using commercially prepared stucco, you must follow manufacturer’s instructions. Do not apply stucco if the weather temperature is less than forty degrees.
Colour and Texture
Despite being a low-cost construction surface, stucco is widely used because it has a wide colour and texture range. This gives stucco huge potential for home customization. Colour aggregate and pigments can change the colour of the material. Specialists will use white cement as a base to achieve the broadest colour range.
Can Stucco be Stained?
Stucco can be finished with natural color or can be mixed to produce any preferred color. Some contractors tend to use warm colors such as yellow, pink, or orange. Beige is one of the most favorite colors used in stucco. However, when speaking of colors, white has always been preferred over other colors. Of course, white is always good for any home. Leave the mortar to dry out for at least six weeks before applying cement paint or color wash if required.