Interior vs. Exterior Paint: What's the Difference?

It might seem like a simple question, but the difference between interior and exterior paint is significant. Each is formulated with a specific set of challenges in mind, and using the wrong one can lead to poor results and even health concerns.

The Demands on Exterior Paint

Exterior paint is designed to be a suit of armor for your home. It needs to withstand:

• UV Radiation: Constant sun exposure can cause colors to fade and the paint to break down. Exterior paints contain special pigments and binders that are resistant to UV damage.
• Moisture: From driving rain to morning dew, exterior paint must form a breathable barrier that keeps water out of your walls while allowing any trapped moisture to escape.
• Temperature Changes: It must be flexible enough to expand and contract with the siding as temperatures fluctuate, preventing cracking and peeling.
• Mold and Mildew: Exterior formulas contain additives called mildewcides to resist the growth of mold and mildew.

The Demands on Interior Paint

Interior paint is all about aesthetics and livability. Its primary concerns are:

• Durability and Scrubbability: It needs to stand up to scuffs, stains, and cleaning, especially in high-traffic areas like hallways and kitchens.
• Low VOCs (Volatile Organic Compounds): Because it's used inside your living space, interior paint is formulated to have very low or zero VOCs. VOCs are chemicals that can be released into the air and cause respiratory issues. Exterior paints have much higher VOC levels that are unsafe for indoor air quality.
• Finish and Appearance: Interior paints come in a wider range of sheens (from matte to high-gloss) to achieve specific decorative effects.

Can You Use One for the Other?

Never use exterior paint inside. The high levels of VOCs and mildewcides are not safe to breathe in an enclosed space and can off-gas for months.

You shouldn't use interior paint outside. It simply isn't built for the job. It will quickly fade, crack, and peel, offering almost no protection against the elements. You'd be repainting within a year.

Choosing the right paint is just as important as the prep work and application. By using the correct, high-quality formula for the job, we ensure your paint job is beautiful, durable, and safe for your family. ```

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