# How do you estimate the number of screws in drywall?

Although the more closely spaced your studs, the more screws you'll be using to attach drywall panels, you can still figure on an average of one screw for every square foot of drywall. Say your ceiling is 18 feet by 18 feet (5.47 meters by 5.47 meters); this means it's 324 square feet (30.10 square meters). Since a pound (0.45 kilograms) of screws contains about 320 screws, you can get away with a pound of screws for this job.

When you're dealing with drywall, it's a bit more complicated, as you also have to deal with windows and doors. Although you might not be able to subtract the window and door areas from the number of drywall panels you buy, you can subtract the number of screws that would otherwise be in the area occupied by the windows and doors. To know the area you'll be working with, measure the height of the room and the width of each wall. Multiply the height by the width of each wall and add together the total surface area of each.