CSLB C-33 Painting & DecoratingSurface PreparationEasy

A painting contractor is preparing an interior plaster wall that has several small, non-moving cracks, typically less than 1/16 inch wide. The client wants a smooth finish. What is the most appropriate material to fill these cracks before priming?

  1. ADrywall joint compound
  2. BAcrylic latex caulk
  3. CEpoxy filler
  4. DSpackling paste
Show answer & explanation

Correct answer: D. Spackling paste

Spackling paste is ideal for filling small, non-moving cracks and nail holes in plaster or drywall, providing a smooth finish that can be easily sanded and painted.

Why the other options are wrong

  • A. Drywall joint compound is typically used for taping seams and larger areas, and may shrink more in small cracks.
  • B. Acrylic latex caulk is flexible and used for sealing gaps where movement is expected, not for filling non-moving cracks in a wall surface that needs to be sanded smooth.
  • C. Epoxy filler is generally used for structural repairs or very large, deep cracks, and is overkill for small hairline cracks.

Spackling Paste

A gypsum-based or vinyl-based compound used to fill small holes, cracks, and imperfections in interior walls and ceilings.

  • Dries quickly and sands easily to a smooth finish.
  • Suitable for plaster, drywall, and wood.
  • Not designed for structural repairs or moving joints.

Memory trick: Small crack? Spackle it back, then smooth and paint, no turning back.

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