Painting Contractor (C-4A) Practice Exam 2025 - Free Painting Contractor License Practice Questions and Study Guide

Using joint compound or spackle is recommended for repairing small cracks in drywall before painting because these materials are specifically designed for this purpose. Joint compound is a versatile substance that provides a smooth, paintable surface once dried. It can effectively fill in small gaps and cracks, adhering well to the drywall and allowing for easy sanding to achieve a seamless finish. Spackle is also suitable for minor repairs as it dries quickly and is easy to apply, making it ideal for small jobs.

In contrast, caulk is typically used for sealing gaps around windows and doors rather than for drywall repairs. Plywood is not appropriate for filling cracks; instead, it is a construction material used for framing or flooring. Wood filler is formulated for use on wood surfaces, making it unsuitable for drywall repair. Therefore, joint compound or spackle is the optimal choice for ensuring a smooth and finished appearance when preparing drywall for painting.