Combining Interior and Exterior Paints (Can You Mix and Match?)

What do you do with leftover paints?

Everyone knows that interior paint is different from exterior paint. Whether you’re repainting a wall in the kitchen or painting a fence outside, it’s important to choose the right type of paint.

But what if you have leftover gallons of both types of paint lying around? Can you mix interior and exterior paints together?

Yes, you can mix interior and exterior paint, but there are some considerations to keep in mind. The types of paint that can be mixed depend on their base requirements, and there are risks associated with mixing paint, such as changes in paint durability and color. Other factors such as surface type, paint finish, temperature, weather conditions and the presence of chemicals and additives can affect the mixing process. Proper handling of mixed paint can affect the quality and longevity of the paint.

So what happens when you mix interior paint with paint made for exterior surfaces?

What paint components just don’t mix?

Need to know something about storing mixed paint?

In this article I’ll discuss when it’s okay when you should avoid it plus tips on storing any leftover paint.

By the way, before I get too far here, if you want to connect with other homeowners and builders and get more great ideas for your home to make your space the best, join my free private Facebook group , Reshape Reality here.

Can interior and exterior paint be mixed?

When it comes to mixing paint, there are some types of paint that can be mixed and some that cannot. The short answer in some cases to mixing interior paint with exterior paint is Yesbut before you attempt to do so, there are a few factors to consider.

For starters, VOC (volatile organic compound) emissions from paint are an important factor to think about. These gases can be dangerous to your health and your environment, so it is essential to understand the off-gassing concentration of the paints you plan to mix.

Furthermore, exterior paint typically has a higher concentration and release of VOCs than any other type of paint; this can be particularly dangerous if used indoors for indoor purposes, as VOCs can damage indoor air quality over time.

In addition, it is essential that both paints have the same base; oil-based paints must only be mixed with other oil-based paints, and water-based paints can only be mixed with other water-based paints.

It is also important to note that when you combine different brands of paint, there may be unpredictable colors due to the difference in ingredients between each. This could result in a «spotty» finish on walls or furniture after drying due to the lack of consistent color coverage during application and curing.

If, after considering these risks, you still decide to mix the two types of paint, the best practice is to mix them in a well-ventilated area using a drill or hand mixer. Wear gloves that are safe for use with paint materials and a mask as additional protection against escaping fumes while these paints are being mixed together.

Furthermore, sift for lumps whenever possible, as clumping can cause handling difficulties during application processes as well as inconsistency in surface finish once dry and cured. And remember, exterior paints take much longer to cure and can be off-gassed for months.

To summarize: While it is technically possible to mix interior and exterior paint, be aware of the essential differences between them in terms of base ingredient composition, brand origin, varying amounts of VOC off-gases present that require relief/venting especially during mixing/application processes— not forgetting additional screening steps when necessary— and an extended period of time to fully heal. It all depends on how comfortable you feel to do this responsibly without compromising safety issues, both inside your home and elsewhere where the project site will be after the work is done.

Key featuresDetails
VOC emissionsConsider the clearance level present in each type of paint, especially exterior paints that have a higher VOC concentration.
Paint baseMake sure both paints have the same base (oil-based paints with other oil-based paints and water-based paints with other water-based paints) for proper mixing.
Brand differencesMixing different brands of paint can lead to unpredictable color results due to the different ingredients in each brand.
The mixing processMix the paint in a well-ventilated area using a drill or hand mixer. Wear gloves and a mask for safety and sift to avoid clumps to avoid inconsistency in surface finishes once dry and cured.
Paint storageStore any remaining paint mixture immediately in an airtight container after all application is complete.

Understanding interior and exterior paint

When choosing the right paint for a project, it’s important to understand the difference between interior and exterior paints. Interior paint is intended for use inside homes and buildings, while exterior paint is formulated to withstand harsh weather conditions and outdoor use. Exterior paint is more resistant to elements such as moisture, temperature changes and UV rays than interior paint.

In addition to resistance to the elements, there are several types of paints that can be used for interior and exterior applications. Oil-based paints offer better adhesion and durabilitybut they have a strong smell and release more VOCs, so they are not always the best choice for indoor use. Latex or water-based paints are generally better for interior projects due to their quick drying time, low odor and lower VOC release. compared to oil-based paints.

VOCs are chemicals released from paint as it dries, which can contribute to air pollution and have negative health effects on people with respiratory problems.. For this reason, Low VOC or zero VOC formulations are available from some manufacturers to reduce environmental impact.

The finish of the paint can also affect the overall appearance after drying as well as durability over time. Flat paint or matte finishes hide imperfections well, while high-gloss finishes work best in high-traffic areas or surfaces that require light cleaning, but will show any flaws in the surface beneath them.. The finish also has an effect on durability; the exterior paint needs to be able to withstand heat changes, while the interior needs abrasion resistance against scratches and tarnishing over time.

The pigments used in a particular formulation affect many variables, including color accuracy, opacity and fading, which should be kept in mind when selecting a product. Selecting the right brand of paint is also essential; each manufacturer uses different formulations therefore the combination of paints of to different brands without taking this into account could lead to unpredictable results which you may want to avoid by sticking with one brand throughout the project. To ensure consistency throughout the project, it is important to follow each manufacturer’s preparation, application and maintenance recommendations, which often vary for each type of product depending on the intended application.

Different types of paint

There are several different types of paint available, each with their own unique characteristics and benefits.

Latex paint is a popular choice for both interior and exterior projects. It’s water-based, which means it’s easy to clean with soap and water. Plus, it dries quickly so you can finish your project faster. Latex paint also has low VOC (volatile organic compounds) levels, making it an eco-friendly option that is safer for human health..

Oil-based paint is another great choice if you need a durable, long-lasting finish. This type of paint uses a solvent as a base, which makes it more resistant to chipping, cracking and peeling than latex paint. However, oil-based paints take longer to dry than latex paints.

Water-based paint is similar to latex paint in that it uses water as a solvent instead of synthetic resins. It is also environmentally friendly due to low VOC levels and dries quickly like latex paint. Water-based paints come in a variety of colors and finishes, just like other types of paint.

Acrylic paint is another versatile option that can be used on many different surfaces including wood, metal and plastic. It uses acrylic resins as its main component and has low VOC levels, making it safe for indoor use. Acrylic paints also dry quickly and are easy to clean with soap and water.

When choosing the right type of paint for your project, don’t forget the different finishes available such as flat, satin or semi-gloss. Flat finishes are low gloss and are best suited to areas that don’t require a lot of cleaning, such as ceilings or walls, while satin finishes have a higher gloss, making them more durable and easier to clean, perfect for high traffic areas such as hallways or bathrooms. Semi-gloss finishes they have the highest level of gloss, making them the most durable and easy to clean of all three finishes, ideal for doors or trim.

Choosing the right type of paint depends on your specific needs and preferences. If you are looking for a greener option is easy to apply, then latex or water-based paints are good choices, while oil-based paints are ideal when durability is needed, but may emit higher VOCs. Acrylic paints offer versatility on many surfaces, while different types of finishes offer options depending on the requirements of use, ensuring long-lasting results from the painted surface.

Paint typeDescriptionBest used forProVersus
Matte paintFlat, non-reflective finishWalls with imperfections or surface defectsHides imperfections well, great for a comfortable, understated lookNot very durable, hard to clean
Satin paintSoft glow, low-reflective finishHigh traffic areas such as hallways or doorwaysEasy to clean, more durable than matteIt can highlight surface imperfections, not very forgiving of brush movements
Semi glossyGlossy finish, high reflectivityHigh humidity areas such as kitchens or bathroomsVery durable, resists moisture and stains wellIt can be difficult to apply without visible brush strokes
High glossShiny, mirror-like finishCarpentry, cabinetsVery resistant, easy to clean, highlights the architectural detailsVery reflective, can highlight imperfections, requires very precise application

The effects of mixing different types of paint

When mixing different types of paint, you should keep in mind that the final result may not be what you expected. Mixing paints with different formulations and pigments can result in uneven color and texture, giving your paint a mismatched look. To avoid such problems, it is essential to mix the paint well and evenly.

It is important to note that even if you are using the same type of paint, if they have different formulas or were made by different brands, they may not mix properly. Thus, it is best to test a small amount of mixed paint before applying it to the entire surface.

Mixing oil-based and water-based paints is not recommended, as they do not mix well. Oil-based paints usually have a solvent-based formula that will resist water-based formulas and make them difficult to mix. The result is likely to be an inconsistent finish with poor surface adhesion. For this reason, it is not advisable to use water-based paint outside where it is exposed to harsh weather conditions, as it may not be durable enough.

Interior paint is designed for indoor use only and will not withstand outdoor elements such as moisture, UV rays and other hazards. Using interior-exterior paint is not recommended unless it is touch-ups or small projects where long-term durability is not an issue.

When mixing paints, other factors to consider include base, paint finish, color, temperature, weather conditions, chemicals and additives, resins, and volatile organic compounds (VOCs). Mixing different types of paint bases can create an unstable mixture that will not work well. Paint finishes can affect the final appearance of mixed paints, especially when combining paints with significantly different finishes.

Colors can also change when you mix different types of paints, making it difficult to get the shade you want. Temperature and weather conditions can affect the drying time and curing of the paint, while the chemicals and additives used in the manufacture of these products can also affect their properties.

Resins are also a critical element in determining how durable your finished product will be after painting. Resins from different types of paints when mixed together can have a negative impact on how durable or flexible the painted surface will become over time, leading to peeling or chipping.

Exterior paints are higher in VOCs, which are emissions of gases the paint gives off over its lifetime that can cause health problems when inhaled over long periods of time – especially for exterior paints that emit more VOCs than any other kind, thus presenting more danger when used indoors..

To minimize the risks associated with mixing paints always follow the manufacturer’s instructions carefully, avoiding mixing incompatible products whenever possible; ensure that appropriate safety equipment such as gloves and masks are used; mix in well-ventilated areas; test on inconspicuous areas first before using on visible surfaces.

Factors to considerMixing effects
Paint baseMixing different types of paint bases can create an unstable and unworkable mixture, resulting in an inconsistent finish with poor surface adhesion.
Paint finishCombining paints with significantly different finishes can affect the final appearance of mixed paint, making it less reflective and shiny than the original finishes.
ColorColors can change when different types of paint are mixed, making it difficult to match or achieve the shade you want.
Temperature and weather conditionsTemperature and weather conditions can affect the drying time and curing of the paint.
Chemicals and additivesThe type and amount of chemicals and additives in the paint can affect the mixed product.
ResinsMixing resins from different types of paint can affect the final properties of the mixed paint, making it less durable or prone to chipping or peeling.
Volatile Organic Compounds (VOCs)Exterior paint typically has a much higher concentration and release of VOCs than any other type of paint, which can be harmful when used indoors.

When it comes to mixing paint, best is always follow the manufacturer’s instructions and avoid mixing different types of paint unless they are compatible. Mixing paints can be unpredictable and the end result may not be what you expect. To ensure a successful mix, there are some important steps to follow.

First, it is essential to use proper safety equipment such as gloves and a mask when handling the paint. Additionally, make sure you work in a well-ventilated area to avoid inhaling any harmful fumes.

When you mix the paint, use a paint mixer or drill to thoroughly mix the pigments and additives. This will help ensure an even distribution of color in the mixture. Before applying the mixed paint to your surface, it is recommended to test it on a small section first. This will help you determine whether or not the mixture is consistent and whether or not it will produce the desired results.

It is essential to note that even if you use the same type of paint, if they have different formulas or come from different brands; it may not mix properly. Thus, test a small amount of mixed paint before applying it to the entire surface is always recommended.

Storage of mixed paints

If you don’t store the paint correctly, the interior and exterior components will separate while sitting dormant on a shelf. This causes the heavier bits to sink to the bottom, making it difficult to remix them back to their original consistency. But with certain tips and tricks, we can ensure that our mixed paint remains of excellent quality for future use.

To keep your «Frankenstein» paint in good condition, you need to make sure that you choose an airtight container. This will prevent any unpleasant fumes from escaping and keep the paint fresher for longer. You should, too label the container with important information such as paint type, base, paint color and date mixed. This will help you remember which mixture to use and avoid confusion.

When storing mixed paint, it is best to store it in a cool and dry place. This will help maintain the consistency of the paint over time. Avoid storing in direct sunlight or in areas with extreme temperatures as this may affect the chemical composition of the paint.

The shelf life of mixed paint depends on several factors, such as the quality of the paint, how it was mixed, and how it was stored. In general, properly mixed paint should last up to two years if stored in a cool, dry place away from direct sunlight or extreme temperatures.

Over time, however, even well-stored mixed paints can begin to degrade in quality. They can separate or become thick and difficult to work with. If this happens, it may be necessary add a small amount of water or other chemicals to dilute or stir the «Frankenstein» mixture back to its original state.

It is essential to remember that even well-stored mixed paints may not be as effective as when first mixed. To ensure that old paints are still usable before starting any new projects with them, test them by painting a small area first and checking their texture and consistency beforehand.

Proper storage of mixed paints is crucial if you want them to remain usable for future touch-ups or repainting projects; saving both time and money in the long run!

Next steps

Want to join others creating the most amazing home redesigns and renovations and get more tips, tricks and hacks on how to make your home the best it can be?

Join my new free private Facebook group, Reshape Reality to connect with other people like you to make your space the best!