A mirror can enhance the appearance and the size of a room, creating a reflection that makes a smaller space seem more expansive. Similar to hanging any other heavy object on drywall, serious damage can occur if the mirror is not braced properly; the drywall could buckle and cave in, the mirror could fall to the ground, and both of these mishaps will leave you with large holes in your wall requiring repair or entirely new drywall. Hanging any item weighing more than 50 pounds on drywall can be hazardous if proper precautions are not taken.
Measure the back of the mirror using a tape measure or ruler, and find a center point. It is important to note how the mirror frame is to be hung, whether you are using hooks, wires or fixing the frame to the wall.
Designate the spot on the wall where you'd like the mirror hung. Using the measurements of the mirror's center point, mark the point on the wall using a pencil. You can use the tape measure, a ruler or a straightedge to make certain that the line is straight across.
Center the plywood at the center point mark. Nail the plywood to the center point of the wall with one nail, allowing the plywood to be adjusted if it is not level. Once a nail is in, use a level above the plywood to straighten it perfectly on the wall. If the plywood is not level adjust it, then nail the plywood securely in place with several remaining nails.
Locate the studs using a stud finder. If you do not have a stud-finding tool, you can locate a stud by driving a nail into the right and directly underneath the plywood. In most homes, the studs are 16 inches off center. If you do not find a stud on the first attempt, measure one inch to the left of the previous hole and try again, keeping the nails directly under the plywood to support the weight of the mirror when hung. Once you locate one stud, the process becomes easier. Measure 16 inches to the left of the first stud and place another nail. If your measurements are correct, you will have found the next stud. Drive one nail into each stud, remembering to do this directly underneath the plywood backing.
Mark off two locations for the wood screws. Space the screws based on the requirements for the frame. For instance, if the frame requires wires for hanging, space it according to the directions included with the frame. However, if the frame requires hooks, the screws will need to be spaced for that purpose. Once the spacing is complete, screw the nails into the plywood and hang the mirror.