How to Prep a Room for Paint
Take off hardware. Take off window locks, lifts, doorknobs, strikes, electrical cover plates, and light fixtures. Tape the screws to each piece of hardware and mark its location; store the items together in a bucket, making reinstalling them easier later on.
Clear out obstacles. Whenever possible, relocate furniture to another space so you can easily navigate the space where you’ll paint. Cover whatever can’t be removed with plastic sheeting, and clear a pathway that’s at least 3 feet wide.
Protect floors. Pros generally avoid using painter’s tape—it’s time-consuming to use. One place we always tape along the bottom of baseboards. Then we tape a broad border of rosin paper to this strip and cover the rest of the floor with plastic-lined canvas drop cloths—these control spilled paint from seeping through. “Protecting the floor will save you time and headaches in the long run.”
Fill holes, gaps, and cracks. Closely check walls and trim for flaws; patch holes, dents, and dings by using ready-mix spackle on walls or wood filler on trim. We use joint compound and mesh tape on wide cracks on plaster walls and flexible patching compound on smaller ones. Fill gaps around the trim by cutting a caulk tube close to the tip, running a small bead, pressing down, and pulling the caulk gun toward you as you work; then, run a wet finger on it to smooth it out.
Sand and remove dust. To make a smooth and even surface for painting, scuff-sand moldings, doors, and windows with 220-grit paper. Use a pole sander with 120-grit paper to smooth walls. (If you’re working on paint that could be more than 45 years old, test for lead first.) Thoroughly remove sanding dust with a vacuum equipped with a HEPA filter, followed by a damp rag or tack cloth
Tip: Don’t over-caulk gaps. Cutting the tip of the tube too big results in dirty joints. Measure the gap, and use a caulk tube labeled with lines showing where to cut depending on the size of the gap. Or start small, near the end of the tip, and adjust as needed.