What is spack (spray plaster)?
Spack is a wall and ceiling finish that is applied by machine spraying and has a granular texture. In Dutch it is also called spuitspack or spackspuitwerk. Spack is widely used in new-build housing, especially on concrete ceilings and on walls of calcium silicate or concrete. It is white as standard, but can also be supplied in other, usually light, colours. The grain is available from very fine to very coarse.
Method
Spack is usually applied in two coats:
- First coat. This is sprayed and then levelled off with a straightedge, so that the substrate becomes even and small irregularities disappear.
- Texture coat. Once the first coat is dry, the second coat is sprayed. This gives the characteristic granular texture.
The spraying machine feeds the material through a pump and hose to a spray gun, where compressed air atomises it onto the substrate.
Application and tips
- Mask everything. Spray mist gets everywhere. Frames, glass, floors, pipes and sockets must be completely masked beforehand.
- Substrate. Fill joints between concrete slabs, construction joints and holes beforehand. Spack hides small irregularities, but not cracks that keep moving.
- Touching up. Small damage can be repaired with a spack roller or an aerosol with texture, but a repaired spot often remains visible under raking light.
- Painting over. Spack can be painted with a suitable wall paint; because of the texture, more paint is needed than on a smooth surface.
- Removal. If you want a smooth ceiling, spack can be scraped off or (more often) plastered over with a bonding coat in between.
Common mistake: “touching up” spack with an ordinary roller and ordinary wall paint. The texture gets clogged and the spot becomes more noticeable rather than less. Choose the same grain or have an entire wall or ceiling resprayed.
Related terms
- Airless spraying
- Decorative plaster
- Spachtelputz
- Plaster coat
- Rubbed finish
- Concrete stucco
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