How to Mount Drywall to Trusses

Measure the length and width of the ceiling. Multiply the two measurements together. This is the square footage of drywall required to complete the room. Measure the length of your drywall sheets. The width is always 4 feet, but the length can be 8, 9 or 10 feet.

Place the toe of the tape measure against the vertical wall at either end of the ceiling. Measure the distance from the center line of the first truss to the center line of the second, and then the third. Measure from center line to center line of each adjacent stud to make certain the distances between truss center lines are consistent. If they are, put your tape measure on one edge of the drywall -- a width edge, not the edges of the lengthwise ends -- and mark the center line distances with a pencil. Do the same to the other width-wise edge.

String a chalk line across the middle of the drywall sheet from each mark on one edge to the adjacent mark on the opposite edge. Snap the chalk line. The chalk line is to demarcate the truss centers when you put the sheet on the ceiling.

Measure for any cuts required if the ceiling is not square. First, measure the width of the ceiling at one end of the wall, then measure lengthwise at a distance equal to that of the length of the drywall sheets. Make a mark on the vertical wall at that lengthwise distance. From that mark, measure width-wise again across the ceiling.

Subtract the short width measurement from the long measurement and record your sum. On one end of the drywall sheet, measure down the edge at a distance equal to the sum and make a mark. Place your chalk like on the mark and string it the length of the sheet and up to the corner. Snap the line.

Score the drywall sheet with the carpenters knife -- score at least halfway through the thickness of the board -- and snap the extra drywall from the sheet by bending the two portions in opposite directions along the score. The drywall will snap with a straight line along the score.

Lift the drywall and place it against the ceiling with your partner, chalk lines down. Slide the sheet against the two perpendicular vertical walls you started your measurements from. Place a drywall screw on the bit of your drill, place the tip against the sheet rock on one of the lines and drill through the drywall into the truss. Continue holding the sheet rock. Drill screws into the trusses, one every 16 inches, along each line. Hang your next sheet adjacent to the first using the same method.