If you’re getting ready to tackle a painting project around your Gold Coast or Northern NSW home, you may be wondering: what’s the difference between interior and exterior paint? Can you use the same paint indoors and outdoors? The short answer is no; interior and exterior paints are formulated quite differently to meet the unique demands of each environment. Let’s take a closer look at the key differences.
Ingredient Differences
The main ingredients in both interior and exterior paints are pigments, solvents, additives, and resins. The key differences between interior and exterior products typically come down to the additives and resins in them. For exterior paints, the additives’ strength is much higher than interior options because the paints need to handle extreme weather conditions outdoors. Here’s how these differences impact the performance and durability of each type:
Mildew Resistance in Exterior Paints:
- Exterior painting products generally contain more mildew-resistant additives to help prevent mould and mildew growth.
- This is especially important in humid regions like the Gold Coast and Northern NSW.
- The additional ingredients in exterior paints result in a thicker and more durable product compared to interior paints.
Composition and Durability of Exterior Paints:
- Exterior paints have higher levels of pigments and binders designed to withstand Australia’s intense sun, rain, and temperature changes.
- The binding resins in exterior paints are softer, allowing them to better resist peeling, chipping, and fading, as well as moisture and mildew.
- Typically, 100% acrylic resins are used in exterior paints, providing superior adhesion.
- These resins also offer impressive alkali resistance, preventing the paint from “burning” on fresh concrete or masonry surfaces.
Binding Resins in Interior Paints:
- Interior painting products are formulated with more rigid binding resins.
- This rigidity makes the paint easier to clean and more resistant to stains, ideal for high-traffic indoor spaces.
- Many interior paint products use vinyl acrylic resins, which enhance scrub resistance and washability.
Sheen Differences
Paint sheen, or the glossiness of the finish, also varies between interior and exterior paints. The sheen affects how shiny a paint is and the level of light reflected from its surface. Interior paints come in a wider range of sheens, from flat/matte, eggshell, and satin to semi-gloss and gloss. These can all be used in different areas to suit different room styles and surfaces.
Gloss paints are best for trims and doors that get lots of wear and may need regular scrubbing, while semi-gloss products have a satiny sheen that works for most interior surfaces, including in high-traffic areas like kitchens and lounge rooms. Flat or matte paint has a velvety look and feel to it and provides a modern look for home interiors. It can help hide bumps and gouges and soften glare in rooms and hallways with large windows or skylights.
Recommended paint sheets for exterior house painting are satin, eggshell, semi-gloss, and gloss. The higher sheen of exterior paint helps it stand up better to the elements. It provides a protective seal that’s less prone to trapping dirt and mildew. Semi-gloss paints are great for wood trims but you might try low-sheen options for cladding or rendered walls to help hide imperfections and improve cleanability.
Application Differences
When applying paints, you’ll also notice differences in interior versus exterior products. The thicker consistency of exterior paint means it requires different application techniques compared to interior paint. Exterior painting is typically more labour-intensive, as the paint needs to be thoroughly worked into the surface to create an even, long-lasting finish.
Cutting in edges and painting trim also takes more skill and precision outdoors, where you’re working against the elements. Interior painting, by comparison, is generally faster and easier, with paint gliding on more smoothly.
Can You Use Exterior Paint Inside Your Home?
It’s not recommended to use exterior paint on interior surfaces. The strength of the additives in exterior paints makes them unhealthy to be around in enclosed indoor areas. Plus, exterior paints have a stronger odour, take longer to dry, and can have a slightly thicker, more textured finish that you may find unappealing indoors. Exterior paint is also generally more expensive than many interior paint options, so the extra cost would quickly add up when you have lots of rooms to paint internally.
Can You Use Interior Paint on the Outside of Your Property?
Using interior paint outdoors is generally not recommended, as it simply won’t hold up well to the elements. Interior paints lack the UV resistance, mildew resistance, and overall durability required for exterior surfaces. They’re more prone to fading, peeling, and cracking when exposed to sunlight, rain, and temperature changes.
The same idea applies when using paint in places it wasn’t designed for—like applying wall paint to furniture.
Putting interior paint on your home’s exterior could lead to major maintenance issues down the line, costing you far more in repainting and repairs than simply using the right product. For guidance on protecting your exterior properly, you can refer to our house painting cost guide to understand the value of using appropriate paint from the beginning.
Tips for Choosing the Right Paint
With so many factors to consider, it’s easy to feel overwhelmed when choosing the right paint for your project. That’s why it’s always a good idea to consult a professional painter in your local Gold Coast or Northern NSW area. Experienced professionals such as the painters at Coverage By Design can assess your specific needs and environment and recommend the best interior or exterior paint products to get the job done right. You can call now to chat with one of our friendly team members.
As you can see, interior and exterior paints may look similar, but they serve very different purposes. Using the wrong type of paint for your project can result in disappointing, and even dangerous, outcomes. When tackling any painting project, take care to choose the right paint for the job! Contact us for more information about our preferred paints for different job types, or get a free quote to have your painting project taken care of ASAP.