Guidelines for Painting Your Home’s Exterior Throughout Monsoon Season

By Jimmy Cordier, Owner, Pinon Painting

At this time of year, we get plenty of customers who are concerned about painting their home’s exterior. While this—monsoon season—is generally a wetter time of the year, on most days, the rain is usually not a big concern.

In Ohio, where I come from, you could count on rain three or four days a week. Between mid-October and mid-April, you could not paint outside. The temperatures were too low, the humidity too high, or there was a total lack of sunshine to dry out wet surfaces. So, we had to figure out how to do all of our exterior painting during the other six months, around the rain (and still, some areas of the country are worse with fog and mist).

Here are a few guidelines for painting the exterior of your home during monsoon season:

Monsoon season typically lasts just 75 days. And of those 75 days, it probably rains only on 30. Even then, your area might not see rain on any given rainy day. Maybe you get less. Maybe you get more.

Certainly, you don’t want to paint on a visibly wet surface. We use a moisture meter to check all raw wood, raw masonry, or semi-transparent finishes. This is the only way to make sure it’s safe to paint because some surfaces can look dry and still be too wet to paint. Painting over a surface that has too high moisture content will cause a paint failure within a year. While a moisture meter used to cost a few hundred dollars, now you can get one at Lowe’s or Home Depot for about 25 dollars. Choose one with probes, and don’t paint until you get a reading of 18 percent moisture content or less.

Pressure washing a home drives the moisture content to 100 percent. But it only lasts for a short time. Your surfaces will be back to zero percent within two to four hours. When it is 18 percent or less, you are ready to paint. Remember that you are actually wetting the surface with paint. It is formulated to work about 18 percent moisture or less.

Of course, you have to consider when the next round of monsoon showers is coming. Paint manufacturers recommend paint dry 18-24 hours at 70 degrees and 50 percent humidity before the rain; that’s a cloudy, wet day in our climate. (Keep in mind: this is just their liability attorneys speaking. If I needed 18-24 hours of drying time, I never would have been able to paint exteriors in Ohio. And no painters along the coasts would be able to work outside, either.) Our sun and low humidity accelerate the drying process.

You should be safe painting up to four hours before the rain. I recommend you allow eight to 12 hours before the rain on deck tops. If for some reason, your home does get hit by rain, it probably won’t do irreparable damage. It won’t affect your prep work. You may just have to put a fresh coat on the affected areas. Rain hitting a freshly coated surface leaves blemishes that are easily touched up or repainted. Of course, this assumes that you didn’t get caught in a downpour that washed off your paint (you’d have to get rained on less than 30 minutes after painting for that to happen).

As always, if you have any questions, visit or call 928.778.2902.