A double layer drywall installation is usually done to improve the acoustic insulation inside a room. While it may not be necessary to install a second layer of drywall, it is indeed helpful in making the installation a lot more resistant to fire, moisture, and sound. Here is a quick guide to installing double layer drywall.
Estimate how many sheets of drywall are needed to be installed to the walls or ceiling. If the installation involves a ceiling, make sure to prepare materials needed for T-braces to support the weight of the drywall (2 by 4-inch wooden boards and nails). Determine whether to install the first layer of the double-layer drywall vertically or horizontally. Usually, double layer drywall is installed vertically for the first layer and horizontally for the second layer. A horizontal second layer is neater to look at, which is why it is usually recommended for the last layer.
Cutting the Drywall
After determining the number of drywall sheets needed for the project and planning how it is to be layered on the wall, prepare the drywall for cutting. Use a T-square and a sharp trimming knife to cut the extra portions of the drywall sheets. It is best to mark the portion to be cut with a pencil first to serve as a guide. Make sure to position the trimming knife at the side of the T-square perpendicularly to the drywall to ensure that the cut side will fit the wall edges perfectly. Allow the knife to cut through the material. The extra drywall will snap off easily from the cut line.
Applying the Drywall
Place the first layer of the drywall starting on one edge of the wall. The wall sheet should be parallel to the wall frame as much as possible. Nail the first sheet of drywall to the wall frame starting from the top portion and secure the other nails 7 inches apart from each other. Nail the drywall to the studs as well. Nail the other sheets afterward following the 7-inch distance between nails.
After nailing the vertical sheets, proceed with the horizontal second layer. The best method to use when installing the horizontal sheets is to start from the top because it makes the job a lot easier. Position the first sheet of drywall firmly against the ceiling. Make sure that the side of the sheet is perpendicular to the vertical wall frames. Lightly nail the sheet starting from one corner and progressing to the parts of the wall frame and studs maintaining a 7-inch distance between the nails. Proceed in this manner until all the sheets are nailed perfectly.
After the installation of the double layer drywall, proceed with the taping. Further instructions on how to conceal nails and joints through taping can be found in other DIY articles.