Plaster is applied to walls by spreading it firmly with an upwards stroke using a plastering trowel, angled slightly away from the wall, and then flattening the trowel at the end of each stroke to smooth the plaster down.
Here's a more detailed breakdown of the plastering process:
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Preparation: Before applying plaster, the wall needs to be properly prepared. This may involve cleaning the wall surface, applying a bonding agent, and/or installing lath.
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Mixing: The plaster mix needs to be correctly prepared to achieve the right consistency. Typically, this involves mixing plaster powder with water according to the manufacturer's instructions.
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Loading the Trowel: Use the plastering trowel to pick up a manageable amount of plaster from a hawk board (a flat, handheld board used to hold the plaster).
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Application:
- Initial Coat (Scratch Coat): Apply the first coat of plaster (the scratch coat) to the wall using a firm, upward stroke. The trowel should be angled slightly away from the wall. The goal is to get the plaster to adhere well to the wall and create a rough surface for the next coat to grab onto. It isn't perfectly smooth at this stage. Score the surface horizontally with a scratch tool after application.
- Second Coat (Brown Coat or Float Coat): After the scratch coat has partially dried, apply a second coat, building on the first. Again, use firm, upward strokes. This coat is typically leveled and smoothed using a tool called a float.
- Final Coat (Top Coat or Finish Coat): The final coat is applied much thinner and is for creating a smooth, even finish.
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Smoothing: Flatten the trowel at the end of each stroke to smooth the plaster down. Use various troweling techniques to achieve the desired finish.
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Drying: Allow the plaster to dry completely. The drying time will vary depending on the type of plaster, the thickness of the coats, and the environmental conditions.
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Sanding (if needed): Once dry, the plaster may need light sanding to remove any imperfections.
