There are plenty of ways to upgrade the look of your property, but painting can be accepted as one of the most popular options. For a complete makeover, we often have to think about both inside and outside of our houses, and from here, the concern regarding interior and exterior painting arises. If we consider the paint components, both consist of four major ones (which we’ll discuss later), but does this mean interior and exterior paint are interchangeable?

While both of these paint types are designed to beautify your home, they significantly differ from each other. If you want to ensure that house painters are giving your Sydney residence the proper painting treatment, it is helpful to understand the dissimilarities between interior and exterior house paint. No worries, as in this article we will discuss some of the common aspects that will help you understand why these two are not similar. Before that, we will build a primary knowledge of these paint types to understand the differences better. So, let’s start.

The Basics of Interior and Exterior Paint

No matter if the paint is for internal or external use for your space, it is generally of two types- oil-based and water-based. Oil-based paint was widely used for the outer side of houses even a decade ago, but when it was seen to be on the harmful side, water-based paint became a go-to option for both exterior and interior. This particular type offers various advantages, including quick drying time, releasing fewer VOCs (Volatile organic compounds), and decreased odour.

The four main common ingredients of both indoor and outdoor paint are pigments, resin, solvents, and additives. Each has a specific role to play.

  • Pigments are tiny particles that give a hue to paint. There are two main types: prime and extender. Prime pigments provide the actual paint shade you see in the can.
  • Resins are essential in shaping how paint performs. It brings pigments together to make the paint film.
  • Solvents are the liquids that carry the ingredients for surface application. In water-based paints, it’s mostly water, while oil-based ones use paint thinner solvents like turpentine, acetone, mineral spirits, and more.
  • Additives give paint different qualities, like making it thicker, helping it spread evenly, and preventing mildew.

What Makes These Paint Different from Each Other?

Interior and exterior paints are not interchangeable. The main difference between interior and exterior paint is in the formulation. The binding resins, pigments, and additives contained within both interior and exterior paints are responsible for the differences.


Though both indoor and outdoor paint consist of similar ingredients, the quantity and choice of these components are mainly responsible for creating dissimilarities. Interior paints use binding resins that are rigid, which makes them easy to clean and resistant to stains. On the other side, exterior paint uses softer resins to withstand fading, mildew, temperature changes, and moisture. As the paint is used on the outer side of a project, it needs to be tough to prevent peeling, so 100% acrylic resin is applied for the best results.

In terms of additives, outdoor paint includes it to accelerate the drying time while improving weather resistance capabilities. So, it often emits a higher level of VOCs. However, indoor paint is not exposed to the outer weather, so they do not require environment-specific additives that are strong and might be harmful to enclosed areas.


The consistency and elements of interior and exterior paint vary because they are made to target two entirely different parts of the house. Other than enhancing the outlook, the paint used for the external part of the house aims to protect the surface from various factors. The exterior of the home is exposed to rain, sunlight and humid weather, which can damage the walls. Exterior paint is specially applied to provide protection from such weather conditions. Also, quality paint used by expert residential painters in Sydney can work as a shield against UV light.

The primary purpose of indoor paint is to complement the environment inside your house while being durable against scuffs and stains. These paint types are usually waterproof and support cleaning to maintain the ambience of the household.


The procedure followed in applying interior and exterior painting contrasts to some extent, for which different considerations need to be remembered. Brush and spray methods are used in both cases, but painting indoors is more sensitive, and extra precautions are necessary. Here, uniform appearance is a primary consideration, as imperfections are easily noticeable. So proper roller and brush techniques are followed.

For external paint, consider the weather is mandatory, which is not applicable for indoor setups. Not only rainy weather but also extreme temperatures, higher levels of humidity and direct sunlight can affect the paint, resulting in an uneven finish. So, exterior paint is best applied in stable weather.


Both indoor and outdoor paints are available in a variety of colours, but when it comes to finishes, exterior paint provides a more limited selection. Flat, semi-gloss, or gloss enamel are the three most available options for exteriors. In contrast, interior paints offer a broader range, including matte, eggshell, satin, semi-gloss, and gloss finish. Also, based on the preference, various faux-finish effects are also achievable.

While going for a specific finish, the homeowner’s choice is the primary determinant in both cases, but for internal finishes, the whole theme and aesthetic of the house play an important role. On the other hand, an external finish is selected considering facts like architectural style, practicality and maintenance.

Can These Paint Types be Substituted for Each Other?

Can you use interior paint outside? To answer simply, it’s not possible. If you use indoor paint outside, it is evident that it will be a wrong move. As it is not strong enough, it’ll peel and crack because of changing temperatures. But can you use exterior paint inside? You might think using exterior paint indoors can be a good idea because it’s tough, but the truth is it’s not. Exterior paint can easily scuff and scratch when applied inside, even though it looks fine on the outside of your house. Additionally, exterior paint releases more potentially harmful stuff into the air (VOCs), which can be risky indoors and cause allergies. Thus, interchanging is not really possible in any case.

Confused About Choosing the Right Paint for Your Home?

If you are interested in giving your Sydney residence a painting makeover but are still not sure where to begin with the paint selection, it is always a wise idea to seek help from professional painters. Experienced painting services will help you select the right paint based on your requirements and budget. Their expert house painters know the correct procedure for every painting and will solve all your painting needs in a hassle-free way.

In conclusion, no matter if you are painting inside of your home or outside, investing in the right and high-quality paint is mandatory for a desirable result. So, to avoid risking the appearance of your living space, make sure you go for the licenced painting company in Sydney that never compromises quality and gives you standard service every time.