How Many Drywall Screws Do I Need Per Room?

Attaching drywall sheets to the wall seems like a straightforward task. Take the drywall sheet, scrounge up some screws, and into the stud, they go. Sadly, its not that simple.

The general answer is 18 screws for every 4x6 foot sheet of drywall.

You need 18 drywall screws per 4 x 6' drywall sheet

But as your project gets bigger, so do the calculations. Let's simplify this once and for all. By the end of this post, you can use a basic calculator to do the math for you. Whether you need to brush up on your skills as a professional or attach drywall to your home, we have the precise guidance you need. We'll cover the types of drywall and screws to exact calculations and common mistakes. Let's get those walls up!

Importance of Proper Drywall Installation

The drywall's durability and safety are crucial factors for any installation. You don't want a drywall sagging or falling apart over time. Thankfully the perfect drywall screw exists, but the number of screws is still variable. An insufficient number of screws poses a risk to the integrity of the building and its residents. On the flip side, too many screws in a sheet of drywall can waste resources and weaken the drywall sheets themselves, making them prone to cracks. The optimal number of screws ensures that your drywall is solid, secure, and long-lasting.

Types of Drywall

Regular Drywall

This is the standard drywall type used in most North American and Canadian homes. This drywall requires screws placed 12 to 16 inches apart in the field of the board (the middle).

This is the standard type of drywall used in most interior walls. It typically requires screws spaced about 12 to 16 inches apart in the field of the board and about 8 inches apart along the edges. Knowing the thickness is crucial; 1/2-inch drywall usually requires 1-1/4-inch screws, while 5/8-inch drywall requires 1-5/8-inch screws.

Moisture-Resistant Drywall

Moisture-resistant drywall, or green board, is designed for damp areas like bathrooms. This type of drywall has a moisture-resistant coating on it. This coating is relatively thin, so regular drywall screws are adequate. Some builders also prefer to use black-phosphate-coated drywall screws to resist corrosion. So installing drywall in damp areas needs the perfect screw length and the perfect coating type.

Fire-Resistant Drywall

Fir-resistant drywall is specifically engineered to resist fire in areas where fire is possible. Areas like garages, fireplaces, and kitchens use this drywall the most. Any place where fire is used, this type of drywall is common. This type of drywall is heavier and has greater density. It needs thicker screws to support its weight on the studs.

Hanging drywall requires specific types and lengths of screws, and the number of screws also differs. Fire-resistant drywall is denser, so screws must be placed closely to hold it onto the studs securely. As the drywall thickness goes up, so does the screw count. Moisture-resistant drywall also has unique fastening requirements, which can affect the total screw count. Don't worry; once you understand these drywall types more clearly, you can easily estimate the number of screws required for the installation. All you need is a few tools, and you're ready.

Tools You Will Need

The type of tools needed for the job are key here. To install drywall correctly, you must be precise. If the screws are sunk deep, they tear the paper, potentially requiring more screws to stabilize the area.

Screw gun or a drill

Between a drill and a screw gun, you must opt for a screw gun whenever possible. A screw gun is preferable simply because it allows for more consistent depth when sinking screws. Precision is the name of the game here. A drill is the secondary choice here since it lacks depth control. If you are using a drill, you must be extra cautious about screw depth. When in doubt, refer to your local building codes for the right set of tools.

Tape measure

How many drywall screws do you need for the job? The answer will primarily rely on how much drywall you want to install. So, a tape measure will be the most important tool in your arsenal. A tape measure will help you locate and mark the studs/framing members in the wall, which the screws will screw into. Secondly, you'll need to measure the size of the drywall sheets required to cover the entire area. Lastly, accurate drywall screw spacing must be ensured for a perfect installation. A tape measure to measure distances between any 2 screws will prevent over or under-use.

Drywall bit

A drywall bit is designed explicitly for drywall installs and will be used alongside your screw gun or drill. This bit ensures that screws are driven straight and to the correct depth. Incorrect bits can lead to screws going in at an angle or varying depths. This makes the drywall less secure. The right bit type ensures a smooth installation process and helps maintain the right screw count by reducing mistakes.

Understanding Wall Studs

Locating and marking wall studs

Studs are the vertical frames within the wall that support the house or building. You must locate them accurately, as the screws will be driven into them. Installing screws through the drywall and into the studs is the only way to ensure a secure installation.

Impact of stud spacing on screw count

Stud spacing is typically on-center in residential construction. This means that you measure the distance from one stud's center to the other's center. The exact spacing impacts the number of screws or drywall nails you will need per sheet of drywall. If the studs are 16 inches apart and you use a 4x8 foot drywall sheet, you will need screws at multiple points along each 16-inch section across the 8-foot height. You can't just put four screws along the drywall edges and call it a day. You need screws at regular intervals across the drywall surface to secure it correctly.

Calculating Surface Area

Length x Width

Measure the length and the width of each wall that needs to be drywalled. Multiply these to get the square footage of each wall. Add the square footage of all the walls in the room. Now you have the square footage of the room. This is the base calculation for an initial estimate of how many drywall and drywall screws you'll need. If you are also planning to put drywall on the ceiling, measure the ceiling, but keep its measurements separate from the total. The ceiling drywall requires more screws, which we will discuss in the next section.

Factor in doors and windows

Doors and windows take up wall space; these are openings within the wall where drywall is unnecessary. Measure the lengths and the width of the doors and the windows. Multiply these to get their respective areas and subtract them from the room's total square footage. This gives a more accurate estimate of the drywall you need and the number of screws required.

These measurements are ideal for calculating the number of screws and the amount of drywall required. Good measurements are foundational to a drywall install. It prevents sagging and crumbled drywall edges, making the space safer for longer.

Screw Spacing Guidelines

Horizontal spacing

The horizontal spacing of the screws will largely come down to the wall studs. In most cases, your studs will be 16 or 24 inches apart, and so will the screws. You want to put a screw at each point where the drywall meets the studs. The closer the studs, the more screws are needed.

Vertical spacing

Vertically, the recommendation is to place a screw every 12 inches. So if you have a 4x6 sheet of drywall, and it's 6 ft high, you need 6 screws along the height of each row. (1ft = 12 inches; 6 ft = 12x6 = 72 inches) So a screw needs to go in every 1 foot vertically. For every additional foot of wall height, you'd need one extra screw.

Corners and edges

In the corners and along the edges of your drywall sheets, the screws must be placed closer together. This is usually 8 inches apart. The edges and corners are more vulnerable to damage, this is because they are holding a major chunk of the weight. The extra support ensures that the edges and corners are more securely attached.

Calculating the number of screws per square foot can give you a pretty solid estimate of how many screws you need. Follow these guidelines, and you'll have a securely attached wall with little to no wastage.

The number of screws needed to drywall a room

By now, you understand what square footage is. We will use that as our base estimate to calculate the screws required for a project. Let's assume that you want to mount a 4x6-inch sheet, which is 24 sq. feet. If your studs are 16 inches apart, you will place 3 screws along the 4 ft width. (4ft = 48 inches; 48 inches/16 = 3). For the 6 foot height, you'd need a screw every 12 inches (1 foot) apart. So you need a screw at every foot for a total of 6.

Mathematically:

Horizontal Rows: 3
Vertical Screws per Row: 6
Total Screws per Sheet = 3 (Rows) x 6 (Screws/Row) = 18 screws for one 4x6-foot sheet.

Multiply this by the number of sheets needed to cover the total square footage to get the estimated total number of screws for the project. Always add a 10% buffer for mistakes or unexpected challenges.

Pro Tips for Efficient Drywall Screw Installation

Drywall installation isn't rocket science. But it isn't easy either. We have some pro-building tips to ensure you stay on track for a safe and timely install.

Pre-Drill Holes: A pilot hole is a pre-drilled hole that makes pushing the screw into the studs easier without possibly cracking.
Use the Right Bit: We recovered this before. A drywall bit will ensure that you don't overtighten your screws. A drywall bit on a screw gun ensures that the screws go in the exact length, all the time, every time.
Screw Pattern: Rather than going left to right and top to bottom while putting in screws, use a W pattern from one screw to another. This holds the wall against the studs while you add in additional screws to secure the hold.
Count Twice, Screw Once: Double-check your screw count before screwing them in. Set aside clusters of screws per drywall to ensure you use the right amount of screws every time.
Using the right screw type and size: A standard drywall screw with a black phosphate coating will ensure the best installation in most conditions. Make sure that the screw is the right length. Based on the thickness of the drywall, make sure the screw goes in 3/4 of an inch into the stud or the framing members behind it.

Conclusion

Installing drywall requires meticulous planning, especially when it comes to the number and type of screws to use. The spacing of your wall studs, the type and size of your drywall sheets, and even the specific tools you use can all affect how many screws you'll need. When it comes to installing drywall, it's important to have a solid understanding of the different types available, take precise measurements, and follow the recommended screw spacing guidelines. With the right planning and execution, your drywall project can surely be a resounding success.