Drywall is a building material used to cover interiors. Drywall installers take care to install the boards correctly to ensure that the finishing process is as easy as possible. If installers deviate from recommended practices, they might make the finisher's job more difficult. For example, hanging drywall backwards adds a significant amount of labor for the finishers. Whenever possible, install drywall according to the manufacturer's specifications.
Drywall has a paper coating designed to create a uniform, smooth surface. If you hang drywall backwards, the rougher backing material will be visible through paint. Also, drywall has beveled edges that ease the process of drywall finishing. Drywall finishers embed paper drywall tape along the seams, so installing the tape within the bevel makes the taped seam rest below a flush level. Finishers then fill the beveled depression with joint compound, which hides the tape.
If you hang the drywall backward, the beveled edges will face the interior of the wall or ceiling, which will make the finishing process more difficult because the taped seams will form ridges instead of resting within the beveled depression. Finishers must repair this by coating each side of the ridges with joint compound, which wastes time and materials.
The most effective method is to hang drywall so that the correct side faces outward. In other words, the side with brown paper should face the wood framing, and the light gray and beveled side should face outward. If you use this method, the finishing process will be much easier.
Times arise when a drywall installer may want to hang drywall backwards to save money. For example, if a scrap piece coincidentally fills a bare spot, some drywall installers will install it even if it must be placed backwards. While this is not a recommended method, it won't cause any serious problems later, though it will waste some time. If you do hang drywall backwards, apply several thin coats of joint compound across the entire surface to smooth the roughness. Also hold a flat drywall knife against any seams. If the knife rocks back and forth, you must cover the seam with several thick coats of joint compound; otherwise, you will see a ridge later, even after multiple coats of paint.