Painting In High Humidity
When it comes to painting, we paint outside when the weather dictates and inside when our schedule allows for it. But, should we be taking more into consideration? Like the humidity?
Humidity creates moisture, and we would never paint in the rain, so does that mean we should not paint when it is humid?
We explore that here, so you don’t have to worry about it.
Moisture And Paint
You wouldn’t paint in the rain, and for good reason. The paint would be washed from the wall. But what about moisture? Have you ever painted on a wet surface? Probably not. But paint has water and dries just fine, so is there anything to worry about when it comes to painting and moisture?
The main problem you are going to face here is the drying time. The more humid it is, the more moisture there will be in the air, and the longer it will take paint to dry. Depending on what you are painting, this can pose a problem. You can overcome this by giving lots of drying time, but that is not always possible.
If there is a lot of moisture caused by humidity, the paint's water will take longer to evaporate. This will result in an uneven finish that does not look good.
And, you must be careful that a wall is not moist before you paint it. If there is a lot of moisture in the wall, mold can grow, showing through the paint.
What Is The Correct Level Of Humidity For Painting?
If you are worried about the humidity levels when you paint, there are two ways to measure the humidity before you start. You can check the weather report and base your decision on that, although you might not have an accurate reading for the area you are painting. Or, you can use a humidity sensor for an accurate reading. When humidity is low, you won’t need a specific reading, but you might as the humidity rises and you reach a too high level.
We recommend paining when the humidity is no more than 50%. This gives optimal drying conditions.
You can paint when the humidity is higher than this as long as you are careful, but we recommend avoiding painting when the humidity reaches 85% or more.
Humidity: Wood vs. Metal
We already mentioned mold; you can undoubtedly have mold in wood if the moisture content is high. And wood can swell when there is moisture. Not only can this make it harder to paint, but the wood can change shape as it dries, resulting in a cracked paint job.
Metal won’t have the same issue, but if you have ever painted metal, you know it is harder to paint than wood. Paint does not stick to metal the same as wood, and moisture will make that even harder. The good thing is that it is easier to remove moisture from metal than wood.
Is There Paint I Can Use In Hight Humidity?
When the humidity is high, we recommend not painting until the humidity drops or bringing in fans to lower the humidity. But what about areas where the humidity is high? What paints can I use that are going to last?
Regarding painting rooms with high humidity, such as bathrooms and kitchens, semi-gloss and high-gloss are the best types of paint. They give a durable and hard finish that will stop moisture from seeping in, and moisture can be easily wiped from the paint surface.
How To Paint In High Humidity
While you should not paint when the humidity is above 85%, you can still paint in humidities that are close to that number, but there are some precautions you should take:
Set up fans to remove the humidity from the room or painting area. You can also place a dehumidifier in the room for an hour or two before starting.
Paint at a different time during the day. The humidity will change over the course of a day, so you can still paint on the same day, but you might just need to paint earlier or later in the day.
If you are painting outdoors, paint the surfaces that have been in the sun but are not in direct sunlight. The sun will have removed the excess moisture, and the wall will not dry too quickly.
Moisture will slow the drying process, so paint multiple thin layers instead of thick layers to speed up the drying time.
Dry the surface before painting. While you might not be able to remove all the moisture before painting, you can remove the surface moisture.
What Happens If I Don’t Take Precautions?
If you don’t prepare a high-humidity area before painting and don’t take the precautions listed above, the paint will either not dry properly or the finished paint job will not look good.
If the paint dries too quickly, the solvents will become gummy and will not lie flat when they dry. And, if the paint dries too quickly or slowly, it will result in an uneven finish.
The worst-case scenario is that you paint a wall and have to come back a few days later and clean and paint it all over again. You might even have fingerprints and dirt in the paint if it has taken too long to dry.
Our best advice is to paint when the humidity levels are optimal. Even if you take precautions and prep well when painting in high humidity, you might not get the finish you want. Moving the painting time or day is a lot easier and less hassle than redo the entire job.