How to Plaster Internal Walls
- 1). Apply a thin, less than 1/2 inch, layer of plaster to the wall with the trowel. This first layer is called the base, the render, or the key layer. Cover the entire surface evenly, making sure that the plaster adheres to the wall and packs into any gaps or voids in the wall. Dip the trowel periodically into the bucket of water to keep clumps of plaster from sticking to the tool.
- 2). Draw a criss-cross pattern of thin, shallow notches in the render with the edge of the trowel. Allow the render to dry overnight.
- 3). Apply a second, "floating" layer of plaster over the base, using the same techniques with the trowel. Make the second layer thicker and ensure that the surface is flat and even. Again, draw notches in this layer before allowing it to dry overnight.
- 4). Add a final "skim" coat of plaster over the floating layer. Use a plaster mix with a higher proportion of gypsum and lime and less of cement or sand. Use the same technique to apply plaster with the trowel. Create a decorative pattern, such as peaks or etching, with the trowel. Otherwise, do not notch the surface, instead making it as smooth as possible. Allow the plaster to dry thoroughly.
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