Paint, like skin, is sensitive stuff. So for best results, apply exterior paint when conditions are mild as possible. The main cause of paint failure or premature deterioration is moisture. That means the first requisite is a dry day. Check the paint can label for the recommended drying time, especially if the weather is expected to change soon. Wait several days after a rain, and allow morning mists to evaporate before you begin.
Temperature is another important consideration. Paint needs time to set before the temperature drops below 40 degrees, so it's best not to paint within two hours of sundown if you're expecting cold nighttime temperatures. High temperatures are a problem, too: if the surface gets too hot, paint will blister. In general, avoid painting when in weather above 90 degrees.
The best way to avoid strong sunlight is to paint in the shade. As our animated painter shows, paint the south side of your house in the early morning, then move quickly to the west side as the day progresses. Noontime should find you working on the north side. In the afternoon, do the east side and anything you missed on the south face. Paint the house from top to bottom in horizontal sections all the way across, working around window or door trim. This minimizes overlap marks. After you paint a large section, go back and paint the trim, again from top to bottom. You may want to paint it the next day, following the sun as you did before. Do porches and decks last. Finally, if you can remove things like shutters or doors, do so. Paint them on sawhorses or leaning against your house in the shade.
