To give walls a smooth finish and a neat appearance, plastering is the best way. .
Plastering over masonry, stone and concrete walls level up the undulating surfaces while providing an even layer for painting or cladding. It also helps to hide any defects on walls, where it can be done decoratively, by moulding or carving. It provides a great canvas for further enhancement of walls. Furthermore, it protects the wall from atmospheric influences and conceals porous surfaces.
It is essentially a layer of mortar applied over walls and come in 3 main types:
- Cement Plaster,
- Gypsum Plaster
- Lime Plaster.
Plaster is mixed with sand and water in a specific ratio, known as the ‘plaster mix’. This ratio is extremely crucial to create the correct consistency that would enable binding the plaster with the wall surface firmly. Plaster has the ability to stick on to the wall and it stays intact until any external force removes it. To know more, visit www.myplasterersmelbourne.com.
Plaster is extremely easy to apply but is better done by experts, the process is as follows.
Step 1: Surface Preparation
The wall surface must be prepped up in order to be a stable base for the plaster.
- Mortar joints of the wall must be kept rough and so should be the entire wall so that it can hold onto the plaster easily.
- The surface must also be cleaned thoroughly with wire brushes and water to remove all dirt, oil and grease.
- An already smooth surface must be raked to create a good bond with the plaster and any large cavities must be filled in.
- Wall must be kept wet for at least 6 hours before applying.
Step 2: Pre-preparation
Preliminary work must be done before applying the plaster.
- Dot and Dab: Patches of plaster must be placed horizontally then vertically at regular intervals. The vertical rows are then checked with a plumb bob. Vertical strips known as ‘Screeds’ are formed which become a base/ guide for further plastering to be done.
Step 3: First Coat
- The first layer of plaster must be added between the screeds and levelled with a trowel.
- For undulating surfaces like brick masonry, a thickness of 12mm plaster can be applied and it should be 9mm-15mm for concrete surfaces. An ideal ratio of cement: sand would be 1:3 or 1:6
- The plaster surface is scratched while it is still wet to enable a good bond between this layer and the next one.
Step 4: Finishing Coat
- A finishing layer of plaster, usually 3-4mm in thickness is applied to the wetted base coat. For finish coats, the plaster mix of ratio 1:4 or 1:6 is used.
- The application must be done with wooden floats and steel trowels to ensure an even and smooth surface.
- It must also be done from the top to bottom to collect any excess plaster accumulated and the entire process must be done in one sitting.
Step 5: Post-Plaster Work
- The wall must be cured daily for a week, 3 hours a day, 24 hours after the final layer is applied.
- Any further painting or cladding work can be done after the wall is completely dry.
Since the process requires less time, effort and money, it is very easy to achieve. Plastering offers remarkable benefits in terms of decorative and aesthetic appeal. It assures a great appearance and protects the wall from external forces, ensuring that the wall is well rounded in terms of aesthetic and functionality.