How to Paint Fiberglass Columns

Clean the column of any dust or dirt by wiping it down with a damp cloth. Dirty areas may need to be cleaned using a solution of water and soap and then rinsed with clean water. Allow the column to dry before continuing on

Caulk the joints between the caps and the column and the base and the column. If the gaps are large, insert a foam backer rod to fill most of the space and caulk on top of this. These rods are available at most hardware and home improvement stores and are designed to fill large cracks before caulking them. Let the caulking dry and apply another coat if needed. It is best to apply smaller beads of caulking to minimize the risk of the caulking shrinking and pulling away from the edges as it dries.

Use a 3-inch paintbrush to apply a coat of primer to the columns. The primer should be chosen according to location (interior/exterior) and type of paint to be used (oil/latex and flat/gloss). Check with your local paint store for the right primer for your particular combination of factors. In general, an exterior latex semigloss paint will require an exterior latex primer designed for gloss paints. You can substitute oil for latex, interior for exterior, and flat for gloss in the formula to get the right kind of primer, but it is best to consult your local paint store.

Lightly sand the primer coat with 220-grit sandpaper and wipe the sanding dust off with a rag soaked in denatured alcohol.

Apply the first coat of paint to the columns using a 3-inch paintbrush. Start painting at the top and work your way to the bottom. Dip at least half of the brush in the paint can and remove the excess paint on one side of the brush by wiping it against the can.

Allow the paint to dry and sand the first coat using 400-grit sandpaper and remove the sanding dust like before.

Apply the second and final coat of paint, painting just like in Step 5. You may lightly sand it with 400- or 600-grit sandpaper after it dries, although this is not required and rarely done.