Holding values of the Tapcon masonry screws are dependent on three factors: diameter of the screw, depth of embedment and the strength and type of material into which they are installed.
- Diameter of Screw – Tapcon comes in two diameters of 3/16” and 1/4”. Tension and shear for the 1/4” Tapcon is higher than the 3/16” diameter in all masonry material.
- Depth of Embedment – the deeper the screw is embedded in any masonry material than the better the holding values. The Tapcon must be embedded a minimum of 1” to achieve minimum holding values while maximum embedment is 1-3/4”.
- Masonry Material - solid concrete provides the highest holding values of any of the masonry materials the Tapcon has been tested in. Tapcon can be used in block and brick, with the holding values dependent on a number of factors, such as the strength of the block/brick and the quantity and quality of the mortar in the joint. All test results should be used as a rule of thumb since each brick or block may provide different results.
All the technical information for the Tapcon masonry fasteners are average ultimate tension and shear. Always use a safety factor of 25% or a 4:1 ration to determine the safe working load. All the values are based on the use of the close tolerance drill bits sold by Buildex® Tapcon®. Because the performance of the tapcon will vary depending on many factors, all figures are a guideline and are not guaranteed in any way by the manufacturer Illinois Tool Works, Inc. and CONFAST.com.
Tapcon Product Information
Tapcons come in two head styles: the hex washer head and the flat countersunk. The point of the tapcon is referred to as a nail point. Each tapcon is coated with a blue Climaseal® coating that helps resists rusting. Salt Spray test at 720 hours have shown less than 10% red rust and the same results were achieved after 30 cycles in the Kesternich test.
The Tapcon® brand masonry anchor has an ICC-ES evaluation report ESR-1671, listed under Florida Building code # FL7556 and has been approved by MiamDade #07-0315.03.
The head of each tapcon screws is marked with a letter that designates the range length of the screw. This allows an inspector to determine the embedment depth of the screw by subtracting the thickness of the material from the range length.
Masonry Bits for Tapcon Screws
The bits used for drilling the hole in the masonry for the Tapcon screw are slightly smaller in diameter than the diameter of the Tapcon being installed. The bit tolerance to anchor tolerance is critical. To ensure match tolerance, an ANSI standard type bit must be used. The bit must be used in a hammer drill with the drill switched to the hammer and rotation mode. Before installing the Tapcon screw it is important to clean the hole of all dust and debris.