How Rain and Humidity Affects Paint

Painting outside isn’t just a spur of the moment thing you decide to do. Aside from the final look, you need to take a lot of things into consideration, such as your budget, materials, and yes, even the weather when you finally decide to paint.

As you would know the Philippines has two seasons: the dry season and the unpredictable, sometimes timid, sometimes chaotic wet season. So how does that play into your project? Here we go over how rain and humidity can affect paint, and how to proceed when painting in these conditions.

Conditions that affect paint

Heat from hot days, humidity, and water from the rainy season affect how your paint dries and absorbs into your surface or substrate.

Heat

One major rule in paint projects is to not paint on surfaces that are too hot. Too much heat on your substrate causes your paint to dry faster than required for a durable, long-lasting finish. Heat also causes blisters and bubbles to appear on your paint film. This is why it’s advisable to schedule and plan out your paint project in advance, especially when working tackling your home’s exterior.

Water / Rain

Damp or wet surfaces are not ideal in painting either. For one, your paint’s adhesion to your substrate is compromised, and poor adhesion leaves room for water to seep in. Take a brief

time to inspect the exterior of your home. Notice any bubbles? Another common paint problem that you can blame wet surfaces for is peeling paint.

Obviously, you wouldn’t paint the exterior of your home while it’s raining cats and dogs, but after and you decide to start or proceed with your paint project, make sure to practice thorough ​surface preparation​.

Humidity

Apart from it promoting the growth of mildew and algae, as well as grain cracking in wood, humidity affects paint—water-based paint to be exact—in a way that it interferes with how its water content evaporates to leave a tough coating. Dew created from a humid day dilutes the paint, making it run off of your substrate.

When humidity is too high, you’ll notice what is called surfactant leaching: brown or white discoloration on the surface of the paint. If the paint is exposed to excessively high humidity, the protective qualities of the paint may be compromised. High humidity also works against a fresh coat of paint because it reintroduces water into the incompletely dried paint film.

Humidity also needs to be considered when you’re painting a wood surface. The wood can absorb the moisture in the air, which may compromise the adhesion of the paint to the surface, resulting in peeling or bubbling paint.

Painting for any weather with Island Paints RoofKote

Once you’ve taken weather conditions into consideration, you’ll want to look start for exterior paint as well as roof paint. And when it comes to durable roof coating, Island Paints RoofKote delivers. RoofKote​ is an acrylic water-based coating with excellent durability and unmatched flexibility. Its formula is made to withstand the Philippines’ particular weather conditions.