How many screws are needed per sheet of drywall?
How many screws or nails are needed when installing gypsum panels? The primary factor to determine the overall fastener count is knowing what is the maximum spacing allowed between each fastener. Many variables go into determining the ideal spacing of screws or nails including the thickness of drywall, the spacing of underlying framing members, whether it is installed on walls or ceilings, the orientation of sheets relative to the framing members, and whether or not adhesive is used.
For one of the most common scenarios in residential construction where you hang ½ inch drywall over wall studs spaced 16 inches on center (O.C.), screws should be installed at least every 16 inches. This means that for a 4-foot x 12-foot sheet of drywall you will use at least 40 screws on the entire sheet. How so? A 12-foot-long sheet will cover approximately 10 studs. If you hang the drywall perpendicular to the studs, you end up using at least 4 screws in each stud. So that adds up to a total of about 40 drywall screws.
However, when hanging ½ inch drywall on ceilings with 16 inches O.C. floor joists, screws should be used at least every 12 inches. In this case, you would need at least 5 screws for every floor joist, for a total of 50 screws per 4-foot x 12-foot sheet of half-inch drywall.
The International Residential Code (IRC) chapter 7 table R702.3.5 outlines maximum fastener spacing for various situations. You can use our quick and easy fastener spacing calculator to determine accepted maximum nail or screw spacing for various scenarios. The results this calculator provides are based on information from IRC chapter 7.
What happens if you don't use enough drywall screws?
Not fastening drywall properly by either not using enough screws or installing them improperly can lead to unnecessary and costly drywall repairs such as drywall cracks or screw pops. How can you determine how many drywall screws are needed when hanging drywall?
Check local building codes first
Building codes vary from location to location. Some building requirements are mandated at a state level while others are set by the county, city, town or other municipality. Some areas require contractors to be licensed and file a permit before hanging drywall. Where that is the case, they will usually also require that drywall be inspected before taping and finishing work can begin.
Many municipalities have adopted the IRC standards as a minimum. Where that is the case, IRC chapter 7 has plenty of details to help you determine drywall thickness and fastener spacing. However, some areas have requirements that are more stringent than those outlined by IRC, so it is always good to double-check with your local building department.
What is looked for during drywall inspections? Building inspectors will likely check the type of drywall used in various applications and also verify that a sufficient number of drywall screws or nails are used for each sheet of drywall that was hung. They also check the location and spacing between each fastener. If the building codes in your area include requirements about drywall hanging, please refer to those specific codes to find out how many screws are needed, and what the proper spacing layout should be.
What if building codes in my area don’t cover drywall hanging
Some municipalities do not require permits or inspections for drywall hanging. If that is the case, you can use the principles below to ensure that your drywall is hung in a way that does not lead to unnecessary damage. These principles should cover most residential or commercial construction applications that use lightweight, fire-rated, flexible, moisture-control, or standard sheets of drywall.
Drywall screws pattern
A general rule of thumb is that drywall screws should be installed every 12 inches. This means that when using 48-inch wide sheets, you will have 5 screws in each stud when the sheets are hung perpendicular to the framing; two on the edges and 3 in the field. The screws on the perimeter should be at least ⅜ inch from the edge to prevent break-out.
Drywall nails per sheet
When using drywall nails instead of screws, you should install nails every seven inches. What about the area between the studs? Since wall studs are usually placed every 16 inches, this means that some nails will have more than 16 inches between them. The general principle to go by is that if there is backing behind the drywall a drywall nail should be installed on that backing every seven inches. When using 48-inch wide sheets, this means you will have about 8 nails in each stud if the sheets are hung perpendicular to the framing. The nails on the perimeter should be at least ⅜ an inch from the edge. This means that for a 4-foot x 12-foot sheet of drywall, you will use approximately 72 drywall nails.
As an alternative to spacing nails every seven inches, a pair of nails can be installed 2 inches apart every 12 inches. This won't necessarily change the overall number of fasteners used, but it can make finishing easier. This in essence is like substituting two nails where every screw would have been placed if using screws.
Drywall glue
If you decide to use drywall adhesive when hanging drywall, you will still need to use screws or fasteners, but not nearly as many. A glob of drywall glue should be used at least every 12 inches along the studs and more in areas where you foresee problems with adhesion. In practice, it is usually best to apply a steady stream of glue along the entire stud to ensure consistent adhesion in every part of the sheet of drywall. You will still need to use the same amount of drywall screws or nails along the perimeter of the sheet as you would without using glue, but you will use much less in the field.
Screws should be used every 24 inches in the field of a sheet of drywall to tack the sheet in place while the drywall adhesive dries. When using a 48-inch wide sheet of drywall and framing members are 16 inches O.C., this means you will have two screws on each stud, one at each edge of the sheet of drywall, and one screw on every-other stud in the middle of the sheet.
Other types of drywall
If you are using specialized types of drywall such as Glass-Mat liner panels like the ones used in shaft walls, you should refer to the installation guidelines from the manufacturer and follow their recommendation for the number of fasteners per sheet and fastener location.
What if the studs are 24 inches on center
Most walls are framed with studs every 16 inches. However, ceilings on the upper level of a home or in one-story houses may have trusses that are laid out every 24 inches. In either case, there will be either 16 or 24 inches between screws that are on different studs rather than the recommended 12 inches. This is ok as long as the spacing of fasteners along each stud is adhered to. The span between studs should not affect the holding power as much as the spacing between fasteners on each stud.
The span between ceiling framing members and the type of drywall used is very important. If drywall that is too thin or that does not have enough internal strength is used, the sheet will sag. ⅝-inch drywall is often used on ceilings because it resists the tendency to sag even where framing members are 24 inches O.C.. ½-inch drywall can be used at times on ceilings, however, if a water-based texture is going to be applied or the drywall must support insulation, then sag-resistant ceiling board should be used since standard ½-inch drywall will sag under the increased weight.
Conclusion
Before deciding how many drywall screws or nails to use when hanging drywall, it is best to check local building codes. Some municipalities have codes that require more fasteners than what is outlined above. If that is the case, you should always follow local building requirements. Where municipalities do not comment on this detail, the principles above should help you to install drywall in a way that is secure and helps prevent cracking.