Types of self-tapping screws for fastening plasterboard sheets, tips for choosing and calculating the required quantity

Selecting the appropriate self-tapping screws for plasterboard sheet fastening is essential for a strong and long-lasting installation. Plasterboard must be firmly fastened to wall or ceiling frames with these screws in order for the finished surface to be stable and long-lasting.

Plasterboard-specific self-tapping screws usually have sharp points and fine threads that enable them to grip the material without pre-drilling. This feature lowers the possibility of damaging the plasterboard during application while also making the installation process simpler.

Plasterboard can be used with a variety of self-tapping screw types, each having special features and uses. Coarse-threaded screws for wood studs and fine-threaded screws for metal studs are common variants. The framing material and the particular requirements of the project play a major role in selecting the appropriate kind.

Self-tapping screw selection for plasterboard should take into account screw length, thread type, and head design. To ensure a solid connection, the screw’s length should be adequate to pierce through the plasterboard and embed firmly into the framing material. Regardless of the thread type, the studs or joists being used should match.

To prevent under- or overordering of screws, it is imperative to calculate the necessary quantity. Use about five screws per square meter of plasterboard as a general rule of thumb. However, this can change depending on the installation’s layout, the size of the sheets, and any unique structural needs.

Types of self-tapping screws	Tips for choosing and calculating quantity
1. Coarse thread screws: Ideal for wood studs.	Calculate screws needed by estimating 7 screws per square meter.
2. Fine thread screws: Best for metal studs and thin sheets.	Choose length by adding thickness of board and 25mm for fixing.
3. Self-drilling screws: For fast installation into metal without pre-drilling.	Quantity: Estimate 25 screws per sheet for strong fixing.

What does the concept mean??

There is an official definition for this term. These screws are self-tapping and are designed to attach gypsum board slabs to a metal or wood frame without the need for pre-drilling.

Self-tapping screws, also known as self-tapping rods, are manufactured with a specific type of thread. It ends with a sharp tip on one side and a head on the other.

These fasteners come in two colors: black or phosphate steel with an anti-corrosion coating.

For gypsum board sheets, the screw head needs to have a specific design in order to fit into a countersunk hole. By doing this, the exterior gypsum board sheet will have uniform seams, allowing putty to be applied to the surface before the job is completed.

This is a fairly large and varied group of fasteners that vary from one another in the following ways: the head shape (hemispherical, hexagonal, and countersunk), the tip shape (sharp or drill-like), and the type of thread (rare or frequent).

The self-tapping screw material needs to be stronger than the metal used in the connecting parts in order to attach a metal frame. The surface of self-tapping screws is galvanized or covered with a thin layer of phosphate to prevent corrosion, particularly in high humidity environments.

Fastener functions

Self-tapping screws are required for assembling the components of metal or wood frames as well as for attaching drywall to them. The self-tapping screws used to build a plasterboard partition must adhere to a number of specifications, as gypsum plasterboard sheets must be able to support fairly heavy loads.

• the length of self-tapping screws for gypsum boards ranges from 16 to 152 mm;
• weight depending on length and diameter, for standard diameter 3.5 mm – 1000 screws with a length of 16 mm will weigh 1.08 kg, and with a length of 152 mm – 13.92 kg;
• carbon steel – C1022;
• stainless alloy steel;
• coating: black phosphate; oxide; yellow galvanized;
• thread: rapid or rare;
• Top: acute or in the form of a drill;
• purpose: wood, metal or universal;
• Core for hardness: 290-450 HV;
• Superficent layer in hardness: 550 -640 HV.

Self-tapping screws allow for the easy installation of GKL sheets into profiles without the need for specialized tools; all that is needed is a sturdy household screwdriver. This technology is accessible to even novice installers.

What varieties are there?

Basically, four types of screws are sufficient for all types of plasterboard partitions: two for assembling the wooden or metal frame and one for attaching the GKL lists to the metal or wood frame. For both metal and wood, universal screws can be used in certain situations.

For attaching to a wooden frame

A unique technique is needed to attach GKL sheets to the tree. Their threads are positioned farther along the rod than those of the self-tapping screws used to attach drywall to metal, which is their primary distinction. A high thread pitch keeps the fasteners in place and prevents them from self-unscrewing, ensuring the stability of the wooden frame elements and preventing them from collapsing.

In contrast to metal frames, models for wooden frames lack drill tips. Although options in white and yellowish shades are available in the retail chain, their distinctive gray-black color sets them apart. Screw properties that are used to secure gypsum plasterboard panels to a wooden frame:

• color – black, phosphated or yellow-passivated;
• tip – pointed;
• head – countersunk, cross-shaped slot;
• the thread pitch is radish;
• for a single-layer wall use 3.5×35 mm and 3.5×45 mm;
• material – steel C1022;
• nominal diameter, 3.5/4.2/4.8 mm;
• head diameter, 7.9/8.6/9.1 mm;
• height, 4.6-7.0 mm;
• D external, 3.5/4.2/4.9 mm;
• D internal, 2.05/2.55/3.05 mm;
• thread pitch, 2.7/2.8/3.1 mm;
• slot depth, 2.35/2.5/3.18 mm;
• slot width, 4.5 -5.1 mm;
• head radius, 4.5-5.0 mm;
• minimum breaking moment, 2.0/4.5/6.5 H*m;
• screw length, from 19 to 153 mm;
• weight 1000 pcs. 3.5/4.2/4.8 mm for length 25 mm: 1.35/4.93/9.17 kg.

Twenty to twenty-five wood screws are typically used for every sheet of plasterboard.

To profiles

When making plasterboard partitions, this is the most popular way to mount GKL sheets. There is good rigidity and stability in this design. Fast assembly is achieved without the need for expensive or rare parts or specialized equipment.

Metal self-tapping screws have a cross-shaped slot Ph2. The surface of phosphorized products is more resilient, and their thread shape and sharp tip combine to provide a firm hold with little torque. The phosphated surface allows for drilling up to 1 mm and significantly enhances the screw’s sliding action.

For attaching metal profiles to drywall The most popular kinds of self-tapping screws are these ones:

• TN 25, for fixing gypsum boards in one layer, self-tapping screw with anti-corrosion protection, therefore can be used in damp rooms.
• TN 35-45, for fastening two-layer gypsum board structures.
• LN/LV and TEX 3.5×9.0, used to connect frame elements together.

Features of the components to which the gypsum board is fastened on the metal frame:

• head – secret type;
• slot – No. 2;
• carving – rapid;
• tip – pointed;
• steel grade – C1022;
• external protection – galvanized or black phosphated;
• metal profile thickness, up to 1 mm;
• nominal diameter, 3.5/4.2/4.8 mm;
• head diameter, 7.9/8.6/9.1 mm;
• head height, 4.5-7.0 mm;
• outer diameter, 3.3/4.0/4.7 mm;
• internal diameter, 2.2/2.8/3.55 mm;
• thread pitch, 1.4/2.10/2.3 mm;
• slot depth, 2.3/2.5/3.2 mm;
• slot width, 4.5 -5.1 mm;
• head radius, 4.5-5.0 mm;
• minimum breaking moment, 2.8/4.5/6.5 H*m;
• screw length, from 19 to 153 mm
• weight 1000 pcs. 3.5/4.2/4.8 mm for length 25 mm 1.35/4.93/9.17 kg.

The typical metal screw consumption rate for a single-sheet structure is between 30 and 36 pieces per sheet of TN 25 gypsum board, and between 36 and 40 pieces for double-sheet construction made of TN 35.

The many kinds of self-tapping screws intended for plasterboard sheet securing in building projects are examined in this guide. We’ll offer helpful advice on selecting the appropriate screws depending on wall type and sheet thickness. We’ll also go over how to figure out how much is needed for a quick and effective installation, so your project runs smoothly and safely.

Recommendations for choosing screws

Choosing the right fasteners that satisfy SNiP requirements is essential to assembling a dependable plasterboard partition design, which can range from simple to extremely complex and reinforced. Self-tapping screws offer a tensile or high-strength connection.

Self-tapping screws are not permitted in constructions where shear loads will be applied to them.

Consider the following factors when selecting self-tapping screws for a plasterboard partition:

1. Steel grade and processing option: regular carbon steel, stainless steel and brass. Determine fastener processing by color:
2. black phosphating;
3. white – galvanized;
4. yellow passivated – galvanized with chromic acid treatment.
5. Q permissible depth at spline, 2.02-2.52 mm.
6. Spline, Рh2.
7. Ultimate breaking moment, 3.0 Nm.
8. Core hardness, 245-445 HV.
9. Surface hardness, 450 MIN HV.

The best performance and aesthetic qualities are found in yellow-passivated self-tapping screws with maximum strength; not only do they not rust, but their color complements the wooden frame the best.

Rules for using fasteners

Measure the thickness of the elements that need to be connected before deciding on the screw’s length.

When selecting this kind of fastener, there is a general guideline that applies: it needs to be long enough to fit through the attached portion and penetrate into the base by at least one-third the thickness of the frame element.

For instance, a screw fastening a 40 mm beam and a 12.5 mm sheet of gypsum board should have a length of at least 30 mm, but no more than 12.5 + 40×1/3 = 25.8 mm.

For drywall, the maximum spacing between screws on a metal frame should be 25 mm, and the maximum spacing on a wooden frame should be 30 mm.

Advice on how to install a gypsum board partition using screws:

1. The thickness of the screws is taken into account if the connection occurs close to the edge of the gypsum board or the contractor uses overdried wooden beams. In this case, there is a high probability of cracks forming along the fibers. In order to avoid damage to the frame, it is better to pre-drill a hole with a thin drill.
2. Wooden elements of the structure are better attracted to each other when there is a smooth part without threads under the head of the screw on the base of the screw.
3. To connect the elements of the structure made of metal profiles, first of all, mark the mounting points of the fasteners. It is marked with a thin drill at the desired point.
4. Until the self-tapping screw cuts a groove and takes a stable position, screwing is carried out at the lowest speed of the screwdriver. After this, the speed is increased, and when the cap approaches the surface, the speed is again reduced to minimum.

Installation costs

This is a necessary step in the process before putting in a gypsum board partition. The first step is to calculate the number of self-tapping screws needed to install one sheet of gypsum plasterboard. This calculation is then done for the total amount of drywall.

As an illustration, consider a 5.5 x 2.75 m single-layer gypsum board partition:

• partition height – 2750 mm;
• partition width – 5500 mm;
• dimensions of gypsum board sheets: sheet height – 2.500 mm; gypsum board width – 1.200 m; GKL thickness – 12.5 mm;
• number of layers of drywall – 2 pcs.;
• distance between screws – 250 mm;
• partition area of ​​one side: 2.750×5.500=15.13 m2;
• partition area of ​​both sides: 15.13×2=30.26 m2;
• number of plasterboard sheets on one layer: 15.13/3×1.2=6 pcs.;
• number of drywall sheets on all layers: 6×2=12 pcs.;
• sheets in height – 2 pcs.;
• sheets in width – 5 pcs.

You must account for the margin when calculating self-tapping screws because, on average, there are up to five defective pieces out of every 100 products.

Calculation: how much is required per sheet of plasterboard?

The self-tapping screw calculation for a gypsum plasterboard partition can be based on the seam distance between them or on the precise rate that the manufacturer specifies for finished gypsum plasterboard structures. These distances are typically used for metal (25 mm) and wood (30 mm), depending on the type of frame.

When installing gypsum board sheets in two layers, the space between the screws is shortened; longer screws will be needed in this scenario as well.

1. Calculation of self-tapping screws on a wooden frame along the length: 2.5:0.3×2=17 pcs.
2. Calculation of self-tapping screws on a wooden frame in width: 1.2: 0.3×2 = 8 pcs.
3. The number of screws on a wooden frame 1 sheet of GKL: 2.5×1.2 m: 17+8 = 25 pcs.
4. Calculation of self -tapping screws on a metal frame in length: 2.5: 0.25×2 = 20 pcs.
5. Calculation of self -tapping screws on a metal frame in width: 1.2: 0.25×2 = 10 pcs.
6. The number of self -tapping screws per 1 sheet of GKL on a metal frame: 2.5×1.2 m: 20+10 = 30 pcs.

On the whole wall

The total number of sheets determines how many self-tapping screws are needed to consolidate GCL sheets. Since a partition measuring 2.75 by 5.5 will need 12 GKL sheets on each side, the following formula can be used to calculate the number of self-tapping screws needed for drywall septum:

• For a wooden frame: 25×12 = 300 pcs., with a margin of 5% per defect – 300×1.05 = 315 pcs.
• for metal frame: 30×12 = 360 pcs., with a margin of 5% per defect – 360×1.05 = 378 pcs.

Advantages and disadvantages

Self-tapping screws are the best option for metal structures; however, regular nails can be used for wooden frames, but they will not provide the same strength as even the most affordable self-tapping screws.

Self-tapping screws have the following benefits when installing a plasterboard partition:

1. The special shape of the counter hole makes it possible to quickly tighten the fastener, which increases the speed of assembly and the reliability of the structure.
2. The specific conical shape of the tip allows the self-tapping screw to evenly penetrate the material without deformation.
3. High anti-corrosion characteristics.
4. High strength characteristics and long service life.
5. Possibility of screwing structural elements into the material without a pre-drilled hole.
6. Can be universal for wood and metal.
7. Guarantees neat and even joints between gypsum board sheets.
8. Creates a hole in the material using threads, followed by reliable fixation.
9. An incomplete thread on the rod near the head creates a more reliable fastening of the gypsum board sheet.

The least expensive phosphated self-tapping screws have a number of inherent drawbacks, such as reduced strength and corrosion resistance, increased brittleness, and the potential for slot breakage under extreme tightening. The higher cost of yellow and white screws is a drawback.

Useful video

Watch the video for more details on self-tapping screws:

Making the correct self-tapping screw selection for plasterboard is essential to a good installation. First, think about how thick your plasterboard sheets are. Longer screws are typically needed to secure thicker sheets to the framing behind them.

There are generally two primary classifications of screws: coarse-thread and fine-thread screws. For both metal and wood studs, coarse-thread screws offer a firm hold. For metal studs, fine-thread screws function well because they are made to leave the plasterboard surface smooth.

Accurately estimating the number of screws required is crucial to preventing shortages during installation. Generally speaking, allow approximately 30 screws for every square meter of plasterboard. Adapt this estimate to your project’s particular layout and design.

Take into account the surroundings in which your plasterboard will be installed. Use screws with corrosion-resistant coatings, such as zinc or ceramic, in damp areas, like bathrooms and kitchens. These coatings prolong the life of your installation by providing rust protection.

Video on the topic

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