The Tapcon® Concrete Screw

Tapcon® is a brand name for high quality concrete screws. The name was derived from its own definition — an anchor that "TAPs its own threads/grooves into CONcrete." The Tapcon® was patented in 1976 by ITW Buildex as the first masonry screw. Tapcon® concrete screws are self-tapping screws that are used to anchor a fixture into solid concrete, brick or block. This screw has alternating raised and lowered threads with diamond cut notches (sometimes referred to as Hi-Lo® threads). This Advanced Threadform Technology™ offers superior pull-out resistance and stability. These Hi-Lo® threads also allow for fast and complete dust removal, which permits the Tapcon® to consistently tap its own high quality threads. Concrete screws that are not Tapcon® brand work in a similar manner but are undeniably different from the original Tapcon®. No other screw performs as well as original Tapcons.

Tapcons can be used in solid concrete as well as in brick and block base material. Tapcon® concrete screws can be used in a variety of applications ranging from light duty to medium duty. Some common applications for Tapcons are attaching furring strips, wood headers or plywood to concrete; mounting a flat TV above a brick fireplace; fastening conduit straps and electrical boxes to a brick or block wall; installing sub-flooring to masonry floor.there is a seemingly endless list of uses for this versatile screw!

Other common names for a Tapcon® are:

Concrete Screw Masonry Screw Confast Screw
Consert Screw Con-Sert Screw Cement Screw
Kwik-con Ruff-nex Titan
Tapper The Original Tapcon The Blue Screw
Self Tapping Screw SS Concrete Screw  

Tapcons are made from carbon steel with a special coating called Climaseal®. Climaseal® coating is applied in multiple stages using a dip-spin technology and provides extra corrosion resistance. All generic concrete screws are also blue in color, however the only similarity to the Climaseal® coating is the color. It is the Climaseal® coating that allows Tapcons to be used in ACQ treated lumber.

Tapcons are also available in 410 stainless steel with a Climashield™ coating. The Climashield™ coating is applied in a three coat, dip-spin process that further enhances this product's corrosion resistance.

Tapcons are available in two head styles: Slotted Hex Washer Head and Phillips Countersunk Flat Head.

Standard Blue Tapcons are available in the following sizes:

Hex Head Flat Head
3/16" x 1-1/4" 3/8" x 2-1/2" 3/16" x 1-1/4"
3/16" x 1-3/4" 3/8" x 3" 3/16" x 1-3/4"
3/16" x 1-3/4" 3/8" x 4" 3/16" x 2-1/4"
3/16" x 2-3/4" 3/8" x 5" 3/16" x 2-3/4"
3/16" x 3-1/4"   3/16" x 3-1/4"
3/16" x 3-3/4"   3/16" x 3-3/4"
3/16" x 4"   3/16" x 4"
     
1/4" x 1-1/4" 1/2" x 2-1/2" 1/4" x 1-1/4"
1/4" x 1-3/4" 1/2" x 3" 1/4" x 1-3/4"

Installation of a Tapcon® concrete screw is a simple process. Follow the steps below to install these concrete screws.

  1. Using a hammer drill and a correctly sized carbide tipped masonry bit, drill a pilot hole 1/4" deeper than the screw will be embedded.
    ** Important note: Hole tolerance is critical when installing Tapcons. The 3/16" diameter Tapcon® requires a 5/32" bit, and the 1/4" diameter Tapcon® uses a 3/16" bit.
  2. Next, clear the hole of all debris and insert the Tapcon® concrete screw through the hole in the fixture and into the hole in the base material.
  3. With a standard drill, slowly drive the Tapcon® screw into the hole in the base material.
    ** Important note: Hex Head Tapcons require a 5/16" nut setter. The Phillips flat head Tapcon® requires a #2 bit tip for the 3/16" diameter screws and a #3 bit tip for the 1/4" diameter screws.

Even with its small size and ease of use, Tapcon® concrete screws still offer considerable holding values. It is important to remember that the holding power of any anchor is always dependent upon the quality and strength of the base material, depth of embedment and proper hole size. When comparing technical data for different manufacturers, it is important to determine what values are being given - ultimate load ratings or working load ratings. Either term is acceptable, but it is important that when comparing products equivalent values are used.

Below is pull out, shear and tension data values for standard Blue Screws:

Pull Out Values – Concrete

Anchor

Embedment

Concrete Strength

Diameter

Depth

2000 psi

4000 psi

5000 psi

 

1"

600

650

800

3/16"

1-1/2"

1090

1090

1220

 

1-3/4"

1450

1460

1730

 

1"

750

800

950

1/4"

1-1/2"

1380

1820

2170

 

1-3/4"

2020

2380

2770

Shear Values – Concrete

Anchor

Embedment

Concrete Strength

Diameter

Depth

2000 psi

4000 psi

5000 psi

 

1"

720

720

860

3/16"

1-1/2"

860

860

860

 

1-3/4"

870

990

990

 

1"

900

1360

1440

1/4"

1-1/2"

1200

1380

1670

 

1-3/4"

1670

1670

1670

Tension and Shear in CMU (1" embedment)

 

Tension (lbs)

Shear (lbs)

Anchor

Light

Medium

Light

Medium

Diameter

Weight

Weight

Weight

Weight

3/16"

220

340

400

730

1/4"

250

500

620

1000

Holding values for the stainless steel Tapcons are as follows:

Pull Out Values - Concrete (3000 psi, cured 40 days)

Anchor

Depth of Embedment in Solid Material (inches)

Diameter

1"

1-1/4"

1-1/2"

1-3/4"

3/16"

964

1080

1360

1595

1/4"

1381

1616

2041

2332

Pull Out Values - Hollow Block

Anchor

Depth of Embedment in

 

Diameter

Solid Materials (inches)

3/16"

540

1/4"

754

Shear Values

 

 

Shear Strength

Shear Strength

Anchor

Anchor

3145 PSI Hard

Lightweight

Diameter

Embedment

Rock Concrete

Hollow Block

3/16"

1-1/4"

1460

1096

1/4"

1-1/4"

1622

1218

The holding values in the charts above are ultimate holding values for the list of embedments shown. A safety factor of 4:1 (or 25%) is generally accepted as a safe working load. For example, if the ultimate shear value for a 1/4" diameter Tapcon® with a 1-1/2" embedment in 4000 psi concrete is 1380 lb., then the safe working load for that screw is 345 lbs. It is also important to remember that this value is the holding value for one Tapcon® screw. If eight concrete screws will be used to fasten a fixture, the combined shear value would be 2,760 lbs. (345 lbs. X 8 screws).

Even though Tapcons are small in size and are easy to install, these concrete screws are still resourceful fasteners. They are available in both standard Climaseal® coated and stainless steel and are offered in two head styles in a variety of lengths to meet a wide range of requirements.



 

Please remember with all fastening jobs to keep safety in mind. Always follow safety instructions on all tools, and refer to manufacturer's installation instructions when available and always remember to wear safety goggles!

Article written by: Michael Pistorino, Concrete Fastener Specialist