Is There a Difference Between Interior and Exterior Paint?

Is There a Difference Between Interior and Exterior Paint?

Interior and exterior paints are made for different purposes. Exterior paints need to hold up against the elements, while interior paints are made to protect the walls inside your home. If you want to understand what makes them different, it is important to look at the purpose for each type and how it is made. 

How Is Paint Made?

All paint contains certain components, including pigment for color, solvents for mixing, additives for preservation, and resins for bonding. The difference between oil-based paint and latex paint is the solvent; latex uses water, and oil-based paint uses mineral spirits. The solvent makes the paint a liquid so that you can cover surfaces, and when it dries, the solvent evaporates. 

The resin can be epoxy, acrylic, or other materials, and it creates the bond between the pigment or color of the paint and a surface. The additives can perform a number of different functions that make the paint easier to work with or more protective. Both interior and exterior paints are made of these components, but there are some differences. 

Differences Between Interior and Exterior Paint

The main difference between interior and exterior paints is the type of resin that each one uses. The resin is an important component of paint because it is what allows the color of the paint to bind to the surface. The needs of items that live indoors are different from items that live outdoors. 

Exterior paint is made to handle extremely cold temperatures as well as rain and snow. It also needs to be more resistant to chipping, peeling, and fading from direct sun. The resins used in exterior paint are softer, and they are designed to make the paint durable and strong enough to handle everything it is exposed to outdoors. 

Can You Use Exterior and Interior Paint Interchangeably?

You cannot use interior paint outdoors because it won’t hold up. It will fade, chip, peel, and wear away too quickly because the resins in it aren’t designed to handle outdoor conditions. Although exterior paint will hold up indoors, there are other reasons that you should not use it. 

One issue is that the resins that are used in exterior paint are designed to provide a tough seal, and they can cause outgassing, which can last for a few days. While it cures, it releases VOCs, which are volatile organic compounds, and exterior paint often has mildew and fungicides as an additive. 

Final Words

Although interior and exterior paints are made of the same components, each is formulated for its specified use. Exterior paint uses resins that make it tougher so that it can handle the harsh environment outdoors, and interior paints are made to look great, protect interior items, and be easier to clean. The chemicals used in exterior paints can make them unsafe indoors, so you should always use paint that is labeled for the job you want to do. When you use the right paint for the job, you can count on it holding up better over the years. 

Scroll to Top