Indoor Vs. Outdoor Paint

Indoor Paint

• Indoor paint is specifically formulated to withstand indoor "weathering." This includes resistance to soap, water and scrubbing from sponges. It's also resistant to stains and splatters. Indoor paint is also more opaque than exterior paint, which allows it to more easily cover up stains. This is known as hiding ability. Indoor paint comes in a wide variety of finishes -- or sheens -- including matte, satin, gloss and high-gloss.

Outdoor Paint

• Just as you would suspect, outdoor paint is more formulated for outdoor "weathering." While interior paint is designed to stand up to relatively extreme temperatures, exterior paint is designed to stand up against wind, rain and sun. Outdoor paint is also formulated to expand and contract to stop erosion from cold and hot weather. Similar to indoor paint however, outdoor paint comes in a wide variety of finishes including matte, satin, gloss and high-gloss.

Using Outdoor Paint Indoors

• A somewhat common misconception is that outdoor paint is tougher than indoor paint, making it more durable. The problem is that interior and exterior weathering circumstances vary greatly. This means that exterior paint may be tough against expansion and contraction, but it can peel and chalk if used on indoor surfaces. Outdoor paint also has harsh fumes that should not be inhaled.

Using Indoor Paint Outdoors

• Indoor paint is specifically formulated against indoor weathering, which means that if you apply it to exterior surfaces, it will crack, peel and erode relatively quickly. It's simply unable to withstand the type of weathering that outdoor paint can withstand. The sun, in particular, is extremely damaging to indoor paint, whereas outdoor paint won't fade nearly as quickly.

Summary

• While it may be tempting to use that leftover can of outdoor paint on your living room wall, don't do it. Outdoor paints and indoor paints are both chemically formulated for their respective purposes. It can even be downright hazardous to use outdoor paint on interior surfaces. Conversely, using indoor paint on the outside won't be effective for more than short period of time. While some companies may put different labels on similar items in a scheme to sell more product, this isn't true with paint.