Drywall is made from treated gypsum, which centres between two layers of paper material. There are different types of drywall for different types of projects. Among them is a sag-resistant drywall for ceilings, water resistant drywall with a treated core that is used for bathrooms and kitchens, and an abuse-resistant drywall used for schools and hospitals.

Drywall sheets come in a variety of sizes, such as four by eight, four by ten, or four by twelve feet long. Drywall panels are generally hung horizontally on walls that are up to eight feet tall. Anything over that has them installed vertically.

Drywall is measured and cut to fit different wall sizes and to accommodate light switches and electrical plugs. A utility knife is all you really need to cut it with. By scoring the face paper with the straight edge of the knife, the board can be broken away from the cut. Then all you need to do is trim the back paper.

If you ever wondered how they make those curved corners, flexible boards of a quarter inch rather than half inch are used to create this effect. Installing drywall is a delicate process. Gypsum panels must be fastened tightly to the framing with drywall nails or screws but without breaking the surface paper or fracturing the core. Each of the panel joints must be aligned or it impacts the finishing process by creating blisters and cracks.

A plaster-like compound is used to fill spaces between the drywall panels, after which drywall tape is applied. There may be several subsequent compound applications. However, simply using a dirty bucket to mix the compound can create unsightly surface lumps and scratches.

Sanding is necessary to remove the excess compound. Scratches, craters, and nicks are also filled with joint compound then sanded to hide imperfections. Sanding is generally done with sandpaper or an abrasive-mesh cloth. Using excessively coarse materials to sand and excessive sanding can scuff the panel paper and leave visible scratches.

Taping and sanding can be an extremely messy job, but it’s also the most important when it comes to the look of the finished product.  Yannick Devost, Product Manager of Drywall Products for CGC, describes, “With a good taper, most of the time, there is not much to sand. It’s a tough, tough job for someone who doesn’t have any experience. Then you’re going to get tons of dust. It’s from putting on too much compound. Then you have to sand the whole thing.

“Whenever you see nail pops, it’s more from the drywall application. Maybe it was not properly screwed to the wall and there was some movement.” When you see those “fish eyes,” this is where someone did not do a good job at finishing and left some air voids. “This should not happen, but when the guys go fast, they’re not an experienced taper, or they cut corners, this is what can happen.”

Taping blisters are a problem that can stem from an inexperienced taper. They may not apply enough compound under the tape, so it doesn’t adhere properly. It also doesn’t help if the drywall was not installed tight enough.

Then you can have some movement on the joints that can cause cracking.

This is a job where experience is everything. Even so, it’s important to remember that drywall ingredients are not synthetic therefore the finish is not perfectly smooth.

“One of the misconceptions if you go into a custom house or condominium is people think that drywall will have a perfect finish – like glass,” says Devost. “It’s not perfect. Even if the drywall installers and tapers did a great job, you’ll still see little imperfections.” The Gypsum Association recommends you look at a wall from four feet away in normal light. Sometimes you will have an imperfection that will need to be fixed, but if you don’t see anything, then start to look too closely with a brighter light, you’re bound to see small imperfections.

To have a perfect wall, there are two options. “You can apply a small coat of joint compound overtop of the drywall. Builders will do that when there is critical lighting, such as a ceiling-high window. There is also a paint that is thicker than regular paint and primer you spray on the wall.” Even so, after a bit of coloured paint and a few pictures, who’s going to notice?