Plastering is a crucial part of construction that involves creating a smooth and even surface on the walls and or ceiling. However, one of the most common problems that are likely to be encountered when applying plaster is cracking. These cracks not only affect the appearance of a structure but also its strength and sturdiness.
The solution to this problem is to choose the right cement for plastering – a material that provides better binding and improves crack strength. Of all the types that are available in the market, PPC cement is one of the most reliable in minimizing cracks on plastered surfaces.
What is PPC Cement?
PPC cement also known as Portland Pozzolana Cement is a type of blended cement that contains pozzolanic materials such as fly ash, volcanic ash, or silica fumes. These additives play a major role in improving the characteristics of cement and thus is widely used in construction. One of the benefits is the enhancement of the performance of the plastered surfaces especially in cracking.
Why Do Cracks Occur in Plastering?
It is now important to know how PPC cement can be of assistance in minimizing cracks before explaining how PPC cement can be of assistance in minimizing cracks. Some common reasons include:
- Shrinkage: As plaster dries, it shrinks. If the plaster mix is not well proportioned, it will shrink and crack, and this is undesirable for any construction.
- Thermal Changes: This is because plaster tends to expand and contract with changes in temperature and this results in the formation of cracks.
- Poor Cement Plastering Ratio: If the cement plastering ratio is not correct, then the plaster mix becomes weaker and it is more susceptible to crack.
- Low-Quality Cement: Substandard cement can affect the strength of the plaster and this results in early cracking of the plaster.
How does PPC Cement Addresses Crack Issues?
● Improved tensile strength and toughness
Another advantage that makes PPC cement the best cement for crack-resistant plastering is its improved strength and durability. The pozzolanic materials in PPC combine with calcium hydroxide to produce other cementitious materials. This not only enhances the strength of the plaster but also enhances its durability so that it is not easily cracked.
● Lower Heat of Hydration
The heat of hydration is the heat generated when cement reacts with water to form a gel-like substance. Thermal cracks in plaster can be caused by high heat. PPC cement produces less heat of hydration than the other types, thus it is ideal for plastering in hot and humid areas since it has a low risk of thermal cracking and is water resistant.
● Improved Workability
The fine particles in PPC cement improve the workability of the plaster mix. Improved workability means that the plaster will apply evenly and uniformly on the substrate, thus reducing the chances of cracks. Also, the preparation of a good plaster mix minimizes the formation of air pockets, which are also known to cause cracks.
● The cement plastering ratio has been optimized.
It is important to note that the cement plastering ratio is very important to avoid the formation of cracks. A typical ratio for internal plastering might be 1:6 (one part cement to six parts sand), while external plastering requires a mix of 1:4 cement to sand. The incorporation of PPC cement in these ratios provides the right combination of strength and ductility thus reducing the likelihood of shrinkage cracks.
● Water Resistance
Water seepage is a major cause of cracks, particularly in external plastering works. PPC cement is highly resistant to water. The small pores of the material do not allow water to seep into the plaster, thus reducing the chances of cracks developing due to the expansion and contraction of the material when wet. This property makes it the most preferred in projects that require water-resistant cement.
PPC Cement Plastering Tips
To maximize the benefits of PPC cement, consider the following tips:
- Check the right cement plastering ratio depending on whether it is for internal or external use.
- Ensure that you use good-quality sand and clean water when preparing the plaster mix.
- Properly cure the plastered surface by ensuring that it is moist for at least 7 days. This step assists in attaining the right strength and eliminating shrinkage cracks.
- Do not over-trowel the surface as this results in a poor surface layer that is easily prone to cracking.
Conclusion
Plastering cracks are a major issue, but with the right material and workmanship, they can be avoided or reduced to the barest minimum. PPC cement proves to be the best cement for plastering due to its high strength, durability, and water resistance. To achieve the right cement plastering ratio and take advantage of the special features of PPC cement, you can guarantee a smooth and non-crack surface that will last long.