Can You Use Interior Paint Outside? – Explained

If you have some leftover cans of interior paint loitering around your home, chances are you are wondering whether you can use them on the exterior of your home. They don’t look that different, so you might be tempted to use them on your outside walls. But, can you use interior paint outside? Let’s find out. 

You should not use interior paint outside. Interior paint does not come with the proper protective elements to withstand weather effects and UV light. This causes the paint to fade away in a short time.

In this article, I will talk more about why you can’t use interior paint outside and the necessary properties of exterior paint. I will also give you some ideas on what you can do with all the interior paint you have leftover. So, without further ado, let’s get right to it.

What Happens If You Use Interior Paint Outside? 

Technically you can use interior paint on outside surfaces. But you should not do it. According to experts, you should not use interior paint outside. Interior paints are usually less resilient to the environment and can easily lose its color if exposed to it. 

Different paints contain different properties, as users use them for diverse reasons. While both exterior and interior paints contain the same pigment and sheen, there’s more to it than meets the eye. So, it may help you save up on some bucks but it won’t serve you in the long run.

And that’s why before hopping on the bandwagon of using interior paint outside, you need to know why it is not recommended at all!

What Makes Interior Paint Different From Exterior Paint?

While both interior and exterior paints contain some common ingredients, the dissimilarities between these two are evident. Out of many subtle differences, the main difference between interior and exterior paint is the number of resins used in the formula.

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Resin works as a binder that holds the pigment molecules together and allows them to adhere to the painted surface.

Exterior paint must contain the ability to withstand moisture. Even severe temperature changes, especially if you live in a humid area. It also should be durable enough to resist fading, peeling, and cracking as well.

All of these potential risks can mess up with the binding properties of the paint. For this reason, the resins used to bind the exterior paints have to be softer than the interior paint.

Interior paint should be easy to clean, and thus it has to be stain-resistant and washable. Additionally, major temperature fluctuation and moisture issues do not play a role in interior paints. That’s why resin in interior paints tends to be much stiffer compared to exterior ones.

Nowadays, the majority of interior paints come in water-based formulas. Due to its watery consistency and rigid usage of resins in the formula, it breaks apart way too quickly. Therefore, if you use interior paint on the outer surface of your house, it will begin to peel in a very short amount of time.

Exterior paint contains UV-Protection technology, which helps combat damaging ultraviolet rays. But interior paint has no such ingredients that make it UV-resistant. That being said, using interior paint outside will accelerate the chance of oxidizing and outright decolorization to a great degree.

The texture of interior paint is another reason to avoid it on the outer surface. Unlike exterior paint, interior paints do not consist of additives like sand to make it less slippery. Given it peels a lot and has a slippery consistency to it, it can make the floor slimy and greasy. Even if you do end up using interior paint outside, there is a risk of you tripping over it and hurting yourself.

As mentioned earlier, a water-based interior paint that cannot withstand wear and tear. And, thus it is more likely to fade away as soon as the heavy rain hits. This will result in more peeling than usual.

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And, if you didn’t know already, paints are harmful to the environment. As ingredients used in interior paints are non-biodegradable, you shouldn’t use them outside for the sake of the environment.

Last but not the least, interior paint doesn’t do a great job enhancing the beauty factor of a house.  If you’re all about making the exterior house stand out in the crowd, going for interior paint is a no-no. Interior paint doesn’t contain glitter to elevate the reflective properties.

The hues used for the interior are also quite dull to look at. Therefore, if you don’t want your exterior to look all patchy and cakey, refrain from using interior paint!

What To Do If You Have Already Used Interior Paint Outside?

Despite all the drawbacks, if you already used interior paint outside, it’s not the end of the world. There are so many ways to fix the mishap. First thing first, if you have used high-quality interior paint on the exterior, you can consider leaving it as it is. High-end paints tend to last longer on the surface, even with constant exposure to sunlight, rain, and pollution.

However, the best option would be to use exterior paint to coat it over the interior paint. By layering exterior paint on top, you can increase the durability of the paint time and time again!

If you haven’t used interior paint outside, but are planning to do so anyway, add some exterior paint to the leftover paint. Give it a good mix and paint it on the surface by minimizing the risk of fading. You can also add Silica to your interior paint to increase the durability of the paint.

Things To Do with Leftover Interior Paint

If you are done with your indoor painting project but still have some usable paint left in the can, DIY projects to the rescue! Try out the things mentioned below instead of using them on the exterior surface.

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Store it

If you don’t want to put the paint to use straight away, then consider storing it. If stored the right way, interior paint can last for years.

Make sure to seal the paint in an airtight container and store it in a cool and dry place. It will definitely come in handy for future projects.

Paint the furniture

Instead of tossing out the leftover paint, you can use it to add a pop of color to your furniture. It will elevate the visual aesthetic of the furniture and make it look more vibrant.

Be it a bookshelf or a chair, adding a contrast of color can make old furniture look interesting. Not to mention, it will complement the decor in the best possible way. 

Donate it

If you can’t think of any use for your leftover paint, consider donating it to someone who needs it. This way you can help someone in need without having to waste it and causing any harm to the environment.

Ask your friends if they want it or reach out to the nearby paint business store. Check if they need it for any upcycling projects.


By now, you probably have a decent idea of whether or not can you use interior paint outside. Even though interior and exterior paints may seem like the same thing, they differ highly in their composition. So, stick with using exterior paint on the outer surface to avoid durability issues down the road.I hope this article was able to answer all your queries. Thanks for stopping by and best of luck to you on giving your house a makeover.