Applying cement plaster to a wall involves a structured process to ensure a smooth and durable finish. Based on standard practices and the provided steps, here's how you can plaster a wall.
Applying plaster is typically done in multiple stages, building up layers and smoothing the surface. The following steps outline the process:
Step-by-Step Plastering Guide
Successfully plastering a wall relies on careful preparation and precise application. Follow these key stages:
1. Step 1: Preparation
- Clean the surface: Ensure the wall is free from dust, debris, loose paint, or old plaster. A clean surface promotes better adhesion.
- Repair imperfections: Fill any holes, cracks, or uneven areas in the wall substrate before applying plaster.
- Protect surrounding areas: Cover floors, windows, and adjacent surfaces with protective sheeting or drop cloths.
2. Step 2: Apply PVA To The Wall(s)
Apply a coat of PVA (Polyvinyl Acetate) bonding agent or a suitable primer specifically designed for plastering. This helps seal the surface and improves the bond between the wall and the fresh plaster, preventing it from drying too quickly.
3. Step 3: Mix The Plaster
- Follow manufacturer instructions: Mix the cement plaster powder with the recommended amount of water in a clean container.
- Achieve the right consistency: Mix thoroughly until the mixture is lump-free and has a workable consistency – not too runny and not too stiff. It should cling to the trowel but be easy to spread.
4. Step 4: Apply Plaster Onto The Walls
- Using a trowel: Scoop a workable amount of mixed plaster onto a hawk or spot board.
- Start applying: Using a plastering trowel, apply the plaster to the wall surface, starting from a corner or edge. Use upward strokes to press the plaster onto the wall firmly.
- Cover the area: Apply the first coat evenly across the desired section of the wall, aiming for consistent thickness.
5. Step 5: Skim And Smooth
- Initial leveling: Once the first coat is applied to a section, use a clean trowel or a darby to level and flatten the surface.
- Remove excess: Scrape off any excess plaster and fill in low spots as you work. The goal is to create a relatively flat surface for subsequent layers.
6. Step 6: Scrape
- Control drying: At a specific stage of drying (when the plaster has stiffened but is still workable), the surface may be scraped or keyed depending on the plaster type and desired finish. This step helps to level the surface further and can provide a key for the next coat.
7. Step 7: Second Coat
- Apply the next layer: Once the first coat has adequately dried (but is often still 'green' or slightly damp), apply a second coat of plaster. This coat is typically thinner and is used to refine the surface further.
- Leveling and filling: Apply and level the second coat carefully, filling any remaining imperfections and achieving a smoother surface.
8. Step 8: Finishing Touches
- Final smoothing: Once the second coat has set sufficiently, use a clean, damp trowel or float to polish and smooth the surface to the desired finish. This involves working the surface to close up pores and achieve a glass-like smoothness if required.
- Curing: Allow the plaster to cure properly according to the plaster type and environmental conditions. This often involves keeping the plaster moist during the initial drying phase to prevent cracking.
Following these steps helps ensure a well-plastered wall, ready for painting or other finishes.
