Plaster vs. Drywall: What's the difference?
If the walls at a home walk-through could talk, they'd utter just two words: Pay attention. While you're looking at landscaping, how many stories a home has, how many bathrooms, or if it boasts an upgraded kitchen and appliances, you might not notice the walls themselves. Are they plaster, or are they drywall? What's the difference, and what does it mean for your daily life in a new space?
Plaster Walls
Plaster walls are a bit of a misnomer, because you can't have plaster without lath. Plaster refers to the stuff you see: a smooth yet rustic covering applied by hand at the wall's surface. Behind plaster sits lath, which is made of wood, metal, or rock depending on a home's age. Simply put, the plaster sticks to the lath.
Plaster and lath go way back: Settlers of the American colonies used them in some of the nation's earliest homes. Up until the 1800s, the plaster of choice was lime plaster, which was made using lime, sand, water, and—frighteningly—hog or cattle hair. So, if you're considering purchasing a truly historic home, you might be living with some lurking animal fibers. But that just adds character!
Homes with plaster from 1900 through the 1950s will often have gypsum plaster for interiors and cement plaster for exteriors. These types set more quickly than lime plaster and are more durable. Added bonus: no fibrous binder, and thus no animal hair.
Depending on the condition of the plaster walls in a potential home, you may want to keep them. They often denote the specific period in which a house was built, adding authenticity and character. What's more, they help dampen sound and they’re fire-resistant. Homes with plaster walls also may feature architectural details like curvature that normal drywall couldn't support. As a plaster wall homeowner, I can attest to this—my home features curved arches and corners plus cove ceilings throughout.
So, what's the downside with plaster? Think of it as a bit of a wild animal: beautiful and intriguing yet unpredictable and difficult to care for.
If you're the sort of person who envisions gallery walls galore within your home, you may want to check if those walls are plaster first, for example. You can't just go hammering a nail into a plaster wall—it can crack and fall apart. Hanging art in a plaster-walled home usually takes some planning, some pre-drilling, and even some special additions like picture railing. See what I mean with this SF Gate guide. And if you do crack it, you're going to have to repair it, which may require the help of a professional (although this DIY Network guide might be of use). You can get around this a bit with adhesive Command Hooks, but be forewarned they might not stick depending on the uniform application of the plaster. One of plaster's charms is its textured look, but that could mean an uneven surface for using adhesive hooks and fasteners.
Drywall
Drywalls were an innovation born of necessity. After World War II, a nationwide housing boom brought with it the need for cheaper, quicker, and less labor-intensive installations. Enter drywall, also known as the brand name Sheetrock. Instead of applying gypsum plaster by hand to lath, savvy builders started sandwiching the gypsum plaster between paper, creating huge, firm boards of wall material. That's right: Drywall is just a plaster sandwich. The drywall boards are then cut to fit the size of any given space and fastened to the home's initial framing.
Since the 1950s, drywall has been the go-to for home interiors, with cheaper cost and faster installation being its main draws. It's also plenty durable and can feature different additives to promote fire resistance and moisture resistance. You can also find paperless drywall to promote mold resistance.
Are there any downsides to drywall? Well, not really. It's versatile, hardy, and affordable—but it's not completely invincible.
Drywall without additives can be susceptible to water damage, and homeowners with a heavy hand can still damage drywall while hanging artwork (though it would take a lot more force than with plaster). You've also probably heard the phrase "paper-thin walls." That comes not only from drywall's physical construction but also its ineptitude at dampening sound. Otherwise, drywall is economical and pretty much failsafe, though perhaps not as pretty as its plaster counterpart.