Plastering is a primary way to coat the masonry walls for protection from external agents and provide a polished surface that can be beautified as per your desire. Building Construction uses two popular types of plastering techniques namely Gypsum Plastering and Cement Plastering. Let’s have a look at what they are and the key differences to be noted before choosing one!

Gypsum Plaster VS Cement Plaster

Gypsum Plaster:

Gypsum Plastering is used mainly for plastering ceilings and moldings for windows and elevated ceilings. It is a white cementing material that is made by dehydrating gypsum. It needs to be applied in a plastic state by mixing with water and then hardens and sets by chemical recombination of the mineral gypsum with water. The thickness for walls is generally 11 mm and 8mm for ceilings.

  • Gypsum plaster doesn’t require curing and hence saves a lot of water. Also, the overall drying time is comparatively less than that for cement plaster.
  • Gypsum plaster has higher strength and is less prone to cracking and shrinkage.
  • Gypsum plaster cannot be used in wet areas. However, it is not affected by insects and doesn’t possess the threat of molds and fungus. This is the reason it is advised to use gypsum plastering in hospitals and clinics.
  • It has a fabulous bonding property and hence can be applied on rough as well as smooth surfaces. It gives a clean finished look to the surface for painting.
  • The application time for gypsum plaster is less compared to cement plaster and hence reduces the project cost. But gypsum being costly on its own contributes to the higher cost of gypsum plastering.

Cement Plaster:

Cement Plastering is used for all types of walls and ceilings. It is a mixture of cement with sand and water. The ideal rich cement mixture is made by adding one part of cement with four parts of sand with water. Its typical thickness is between 12 mm to 20 mm depending on the type of wall to be plastered.

  • Pre-curing and Post-curing, both are essentials steps for cement plaster. It requires a lot of water for curing over several days and also is time-consuming when drying the surface.
  • Cement plaster is weak in tension and physical strength and so it can develop cracks over time. Most of this cracking is a cause of shrinkage of the plaster during the drying process.
  • Cement plaster is resistant to moisture but not 100% permeable to vapor. In wet areas like kitchens and bathrooms, the vapor can lead to condensation on the walls that can trigger molds and fungi on the surface and can also become slippery.
  • If a smooth finish is desired, you need to do POP punning after sand cement plaster.
  • The application of plaster is quite a time-consuming process and also the percentage of wastage during application is more, resulting in the increased cost of the project.
  • However, as gypsum is costlier the per square feet cost of cement plasterer is less when compared to gypsum plaster.

Now that you are aware of the basics of both plastering techniques, go through this

 

Comparison between Gypsum Plaster and Cement Plaster

Parameters Gypsum Plaster Cement Plaster
Raw material Gypsum powder commonly with hardeners Cement, Sand and Water
Additional materials Alkali sulfate, alum, borax N/A
Color Pure white Grey
Factory-made Yes No
Curing

Air curing for 24 hours and ready to paint after 72 hours

Wet curing for 7 days and drying plaster for at least 3 days

Application areas

Internal

Internal and External

Minimum thickness

6 mm

10 mm

Final finish

Smooth

Rough

Ease of use

Very easy

Not so easy

Per square feet cost

High

Low

Recyclable

Yes

No

Thermal conductivity

Low

High

Density

Low

High

Fire resistance

High

Low

Rust inhibitor

Yes

No

Gypsum Plaster is advisable for internal plastering and when a smooth finished surface is required. It is also useful for places where sand is not easily available. For external application and plastering in humid areas, cement plaster is the best choice. Overall both of them have their pros and cons so you must decide based on your usage, preferences, and budget.