How to Prepare Straw Bale Walls for Plaster
- 1). Pack any gaps between the straw bales with a mixture of clay and loose straw. Create this mixture by mixing equal parts granular clay and loose straw in a bucket or other large container. If the clay is too dry to be pliable, add a small amount of water. It should be easy to spread but also hold its shape.
- 2). Mix a small batch of plaster in a large bucket. The plaster should be pliable enough to spread easily but firm enough to hold its shape without running. If you are using a prepackaged plaster mixture, there will be directions on the package. If you're mixing your own plaster, there are hundreds of varieties you can use.
- 3). Fill in holes or level uneven areas in the straw bale wall with the plaster mixture. Use your hands or a plaster trowel. You won't need to cover the whole straw wall, just areas that are bumpy. Apply plaster so it is flat to make it easier to cover over again later. The plastering does not have to be perfect because you will cover it up with more plaster.
- 4). Mist the straw walls with a garden hose that has a mister attachment. Mist the walls lightly but don't soak them. Wet only the section you're about to plaster.
- 5). Apply a thin layer of plaster. This will give your main layer of plaster a better grip on the straw bales. Apply the plaster when the wall you're working on is not in direct sunlight. If you can't work out of direct sunlight, string up tarps or other blockades to create shade.
- 6). Mist the first layer of plaster lightly before applying the second layer of plaster.
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