Question: "Should I use bathroom paint? What's the difference?"
Short Answer: Bath paint is a special type of paint--different from ordinary interior house paint--that paint manufacturers advertise as helpful for bathrooms due to two factors:
- Mildew-Inhibiting Properties: Bathroom paint has anti-microbial additives which help resist (but do not completely avoid) mildew.
- Tougher Finish: Should you need to wipe down the surface, bathroom paint is slightly tougher to allow for this, but only with non-abrasive cleaners.
Bathroom Public Enemy #1: Moisture
Bathrooms are wet. Moisture should be your first concern when laying down a fresh coat of paint on your walls, aesthetics second. Moisture affects your bathroom walls in two ways. First, moisture from steamy baths and showers will gather on the walls. Second, water directly from the shower, bath, or sink may contact the walls.
In theory, you should be able to prevent moisture before it begins to form on walls. Bathroom fans, infrared ceiling heaters, watertight shower curtains, backsplashes, and shower/tub tile surrounds, should prevent water from accumulating on paint finishes in the first place.
Theory is wishful thinking. In practical terms, you can't avoid moisture on bathroom walls. All you can do is mitigate it.
Finishes and Mercury
Long before mildew-resistant properties were added to paint, high-gloss paints were the most effective way of dealing with bathroom moisture. The higher the gloss, the better the paint finish performs in bathrooms. That's why in older bathrooms, you'll often find lots of semi- and high-gloss everywhere.
High-gloss paints do not prevent mildew. But they make easy work when wiping down those drippy, brown stains characteristic of bathrooms.
Starting with the flattest finish and working upward:
- Flat - Nice matte coating, but best in low-traffic areas where it is never or rarely touched. Absorbs moisture, so it is bad for bathrooms. Great for halls and dining rooms.
- Eggshell - Slightly "sheeny" and more washable and scrub-able than flat. Like flat, eggshell is good for places without moisture.
- Satin - Satin has a bit of a gloss, and can be used in low-moisture bathrooms.
- Semi-Gloss - Excellent finish for any kind of bathroom. Repels moisture well.
- High-gloss - Best for bathroom walls because high-gloss repels moisture almost as well as if your walls were coated in plastic. Downside is that high-gloss looks awful over large surfaces such as walls. Best for smaller surfaces like trim and cabinets.
The second way paint manufacturers dealt with mildew in the past was to add phenylmercuric acetate (PMA). This fungicide, according to the EPA, was used "in certain latex interior and exterior paints manufactured before September 1991." As the name indicates, PMA contains mercury, which is hazardous to humans.
Isn't there a better way? Yes. And that's why paint manufacturers began to develop bathroom and other premium paints to deal with the problem.
Sherwin-Williams' Take On Bathroom Paint
Steve Revnew, VP of Product Innovation at Sherwin-Williams, tells me that his company is emphasizing premium paints that tackle moisture and provide durability in any part of the home in favor of their original Bath Paint.
For instance, their line of Emerald™ Interior Acrylic Latex Paint contains anti-microbial properties on par with Bath Paint. One problem with flat finishes in moist environments, he tells me, is that they are porous, and have a tendency to trap moisture. Glossy finishes, by contrast, practically "bead water."
Their premium paints contain other additives that mitigate problems that the old bath paints did not address. For example, their Harmony® Interior Acrylic Latex Paint is formulated to help reduce common odors--always an issue in bathrooms.
I asked Revnew which ingredients formed the anti-microbial additives. He didn't have specifics on hand, but said that they are similar to anti-microbial additives incorporated in laminate counters and bathtub finishes. All paint anti-microbial additives are tested and registered with the U.S. Environmental Protection Agency (EPA).
Bathroom Paint Allows For Flatter Finishes
Given the right finish, your need for bathroom-specific paint is diminished.
But flatter finishes are in vogue. For many homeowners, the flatter, the better. That's where bathroom paints come in. They reduce the dependency on gloss finishes.
You can find matte finishes that are specially designed for high moisture areas. Benjamin Moore's Aura® Bath And Spa Matte Finish is one such paint.
Zinsser's Perma-White claims to be guaranteed to prevent the growth of mold and mildew for a minimum of five years. Perma-White can be tinted to off-white, pastel and medium colors. And it comes in eggshell, satin and semi-gloss finishes.
Cost of Bathroom Paint Vs. Normal Interior Paint
Bathroom paint can be significantly higher priced than ordinary interior latex-acrylic paint, close to twice the cost.
At the time of this writing, Benjamin Moore Aura Bath and Spa Paint costs the same as its other premium paint containing mildew-inhibiting additives ($67.99 per gallon). It costs 1.5 times as much as their other premium paint, Regal Select, which is not specifically for bathrooms but can be used there. Finally, it costs 1.8 times as much as its low-end interior latex, which cannot be used in bathrooms.
In most cases, you probably do not need to buy specialty mold/mildew inhibiting bathroom paint. If you have a high moisture content and a history of mold and mildew problems, then you may want to use bathroom paint. A major-brand satin premium paint is fine for bathrooms.