What Is The Purpose Of Roughcast? Difference Between Render And Roughcast?
What Is The Purpose Of Roughcast?
Roughcast is a type of wall plastering material used to create an attractive and durable finish on external walls.
It is typically composed of sand, cement, and lime mixed with small stones or gravel to form a textured surface. This rough texture gives the walls a stippled or irregularly dimpled appearance.
The purpose of roughcast is to provide protection against adverse weather conditions such as rain, wind, frost and ultraviolet radiation from the sun.
It also provides insulation against heat loss in cold climates and helps prevent structural damage caused by moisture build-up over time.
By creating a continuous seal around windows and doors, roughcast also prevents air leakage from gaining access into the property from outside.
Furthermore, it can give a modern look to older buildings and disguise any irregularities within existing plasterwork.
What Is The Difference Between Render And Roughcast?
Render and roughcast are two different types of wall finishes. Render is a slurry mix made of sand, water, cement and sometimes lime that is applied to the walls and left to dry in layers until it forms a waterproof surface.
Roughcast is a wet plaster made out of sand, cement and sometimes lime that leaves a more textured finish than render as it is applied with a trowel or brush.
Render provides better protection against weathering while roughcast offers more decorative options due to its texture.
Is Roughcast The Same As Stucco?
No, roughcast and stucco are not the same – they are two different types of exterior wall finishings. Roughcast is a type of plaster that is textured with an impression from a wet brush.
This texture can be seen on the finished product as a series of ridges and troughs which create a unique appearance to the wall’s exterior.
Stucco is made up of an aggregate material, usually sand or crushed stone along with Portland cement and water.
Unlike roughcast, stucco can be created in both smooth and textured finishes depending on the desired look.
Additionally, while both materials are very durable, stucco is even more resilient against harsh weather conditions such as heavy rains or freezing temperatures making it more suitable for areas with severe climates than its counterpart.
What Is Needed To Roughcast?
Roughcasting is the process of preparing a surface for painting or other coatings. In order to prepare the wall for roughcasting, all loose material should be brushed away and dust and dirt must be removed.
All flaking and cracked plaster must be removed before any work can begin. Primer should then be applied to ensure that the surface is completely sealed from moisture before any further work is carried out.
The primer should then be sanded down with fine-grade sandpaper to create a smooth surface ready for application of the roughcast material. Depending on your preference, this can either come in pre-mixed or dry bag mix form.
Using a hawk and trowel, carefully spread the roughcast material evenly across the wall until desired coverage is achieved, ensuring all holes or cracks are filled as necessary. Finally, once dry and settled, use a stiff brush to give it its signature ridged finish.
How Long Does Roughcast Last?
Roughcast is a durable material that can last for many years. It is generally expected to remain intact for over 25 years, with proper maintenance and care.
However, since it is composed of sand, cement and water–all of which are prone to erosion over time–the lifespan may be affected by several factors, such as the climate in which roughcast has been applied or how frequently it has been exposed to environmental stresses like wind or rain.
Regular inspections and maintenance should be carried out every 2-3 years to ensure the roughcast remains in good condition.
Additionally, a variety of protective coatings can be applied to help protect the surface from weathering and reduce its chances of cracking or fading.
Can You Waterproof Roughcast?
Yes, you can waterproof roughcast with a primer that seals the surface and prevents moisture from entering.
The primer also helps to improve the adhesion of any waterproof coatings that are then applied, like silicone or rubber membranes.
Afterward, two or more coats of a high quality masonry paint should be used to ensure complete exterior protection.
The paint should be able to offer resistance against UV light, mould, mildew and water penetration.
If you choose a breathable paint it can even allow trapped moisture inside the wall to escape making sure that no damp patches form on your walls after rain.
