Painting a two- or three-story house is a risky proposition. The moment you step on a ladder, safety becomes an issue. Reaching up over your head or reaching over to fill that last, unreachable spot can lead to serious injury. If you're determined to paint the gables, peaks, eaves and trim of a high house, use a combination of ladders and rented scaffolding to do it safely. Paint when light is bright but indirect and humidity is low for best results.
Rent a pressure washer, extension ladder with standoff and scaffolding from an equipment rental or home improvement store. When they are delivered, have them set up in the area where you want to begin.
Put on a dust mask and safety glasses. Scrape areas of loose paint from walls and trim with a scraper and wire brush, starting on the ground and working your way onto ladders and scaffolding. Adjust to working in high areas slowly, a little at a time, taking frequent breaks.
Raise the extension ladder as you need to, making sure the lean of the ladder is at least 25 degrees from vertical. Each time you move the ladder, make sure its feet are firmly braced on level ground. Attach the U-shaped standoff to the top of the ladder to give it extra stability in mid-to-high areas. Keep your center of gravity forward of vertical at all times, and do not try to reach areas beyond your wrist when you stretch your arm out to left or right. Climb the scaffolding to reach peaks, gables and eaves.
Pressure wash the exterior of the house. The hard stream of water will knock off dirt and any loose paint you may have missed. Allow the surface to dry for a day or two, especially if the siding is old.
Prime bare areas with exterior latex primer and a paintbrush, following the safety measures in Step 3. It is usually not necessary to prime areas where paint is still intact. Caulk any gaps in the siding and trim with exterior caulk as you go along. Allow the primer and caulk to cure at least a day.
Apply the topcoat of exterior latex paint with a paintbrush, working in long, smooth strokes for even coverage. This time start high on the scaffold because you're now at ease with the height. Still, keep the safety measures in Step 3 firmly in mind at all times. If you are painting the trim a different color, do it now. When finished, break down the scaffolding and return it, doing the rest with ladders.