Painting Exterior Trim
What you'll need:
Here's everything you'll need to get it right the first time.
  • Trisodium phosphate (TSP) or substitute
  • A painter's hat, goggles, dust masks
  • Cloth or plastic drop cloths
  • Plastic bags (large and small)
  • Paintbrushes, at least one 1" and one 2-3"
  • Paint trays and liners
  • Stirring sticks
  • Paintable caulk
  • Wide blade scraper
  • Coffee cans
  • Sand sponge
  • Appropriate chemical resistant gloves
  • Painter's tape (narrow and wide)
  • Extension poles and/or stepladder
  • Newspaper
  • Wax paper
  • Brush comb
  • Brush hook
  • Goggles, respirator and gloves (for alkyd paints)
  • Turpentine or other solvents (for alkyds)


House trim may appear at corners, along the roof line on gables, around windows and doors, or where the siding meets the foundation.

On older Victorian style houses, trim may also be used to separate areas of siding. Painting trim is the last step of your house painting project. It takes some time, patience, and attention to detail —all of which will pay off in the end.

Step 1 - Select Color and Sheen
You can create a sophisticated look for your home with your trim. For a subtle look, choose a shade lighter or darker than the siding. Be sure to select a higher sheen for trim, like semi-gloss or gloss.
Helpful Information
Cleaning Surfaces
Cleaning Surfaces

Washing Exterior Surfaces

A brush attachment and extension pole transforms an ordinary garden hose into an effective cleaning tool.

Load the brush attachment with trisodium phosphate (TSP) or substitute detergent. Rinse with plain water and let dry thoroughly.

Special Cleaning Problems—Mildew

If your surface looks dirty after washing, check to see if the problem is mildew. To check for mildew, first put on chemical-resistant gloves. Then apply a few drops of chlorine bleach to the surface. When working with bleach, protect your eyes by wearing eye goggles. If the dark areas lighten substantially after a minute—without rubbing—you may have mildew.

Mildew discoloration, which resembles dirt, is due to either fungi feeding on oil contained in solvent-based paint or protein thickeners in latex paint. Moisture is the most important single factor in the growth of mildew, which can lie dormant for years. For this reason, discoloration is usually found in damp, dark areas or during prolonged humid conditions.
The mildew must be removed completely before repainting, or else any new coat will soon show signs of discoloration. Paint cannot adhere to a mildewed surface. Spray mildewed areas with a solution of 3 parts water to 1 part chlorine bleach and let the anti-fungal treatment dry thoroughly—do not rinse with water. Let the agent work its magic on your exterior surface.
Masking Exterior Surfaces
Step 1
Use paper and tape to mask exterior water fixtures, drains, and metal work.
Step 2
Mask windows with plastic sheeting and tape. Use your single-sided blade to cut the plastic to fit. First, lay down the tape. Then place the precut plastic over the windows.
Step 3
Throw drop cloths over sidewalks, plants and shrubs. (Be sure to water your plants first and remove the drop cloths at the earliest opportunity.)
Step 2 - Plan
When painting exterior trim, work from the top down —gables, dormers, eaves and gutters, second-story windows, porches and stairs and foundations. If you don't want to mask around window panes, use a paint shield as you work. Scrape off any spatters and drips later. On porch railings, paint all the spindles first, and then paint the horizontal rail pieces. Be careful that paint doesn't "glob" or drip as you work in all the crevices and joints.
Step 3 - Choose the Right Brush
Use the largest size brush that will fit your trim.
Step 4 - Clean and Be Green

More painting to do tomorrow with the same color? You don't have to clean brushes and rollers when you take a break. Wrap them in sealed plastic to stay moist until you are ready to paint again.

Tip: If paint has hardened on the handle or along the edge of the bristles, soften it with warm water so you can remove it before you begin to paint. Make sure you dry the brush before you dip it.

Locate a store
Retail Locator
See How-To Videos
Watch a project from start to finish.
Watch Videos