These stainless steel masonry screws can be used in applications where stainless steel is required to fasten an item or fixture to masonry base materials, such as an electrical junction box, plywood, light fixture or a 2x4.
There are two different head styles are available: the slotted hex washer head for use in applications where the head of the screws sits on top of the surface of the material being fastened and the Phillips flat countersunk for use in applications where the head sits flush with the surface of the item being fastened.
CreteFlex screws are manufactured in a one-quarter inch (1/4”) diameter, which is designated by the first number in the description.
CreteFlex screws are available in lengths from 1-1/4” to 6”, which is designated by the second number in the description. The hex headed screw is measured from underneath the head; the flat countersunk is measured as an overall length including the head.
Diameter of Hole
A 7/32” diameter hole must be drilled into the base material using a hammer drill and a carbide tipped bit that meets ANSI standards. This will ensure proper tolerance for each diameter of both the hex and flat headed stainless steel CreteFlex screw.
Depth of Hole
The hole must be drilled into the masonry material a minimum of 1/4” deeper than the screw will penetrate the masonry. It is important that the hole allows the screw to be installed at minimum embedment depth.
- Minimum Embedment – the CreteFlex screw must be installed in the masonry a minimum of
- Maximum Embedment – the CreteFlex screw must be installed 1-3/4” for all lengths
Thickness of Material Being Fastened
Each different length of Philips flat head or hex head screw is designed to fasten materials of different thickness. The maximum thickness of material to be fastened can be determined by subtracting the minimum embedment depth of 1” from the length of the screw. For example, subtract 1” from the overall length of a 3-3/4” long CreteFlex screw to determine that 2-3/4” would equal the maximum thickness of the material that can be fastened with this length of the screw.
|2,732 PSI Concrete
||Hollow Block (2,070 PSI)
Each box of CreteFlex screws is packaged 100 pieces per box, with one proper diameter and length bit in each box.
Installing CreteFlex Screws
- Drill a hole in the base material using a hammer drill and a 7/32” carbide tipped bit that meets ANSI standards.
- Make sure that the hole is drilled a minimum of 1/4” deeper than the screw will penetrate and will allow the screw to reach minimum embedment.
- Using compressed air, wire brush or vacuum, clean the hole of all dust.
- Insert the pointed end of the screw through the fixture and into the hole in the base material.
- Using a 3# phillips bit tip for the flat head or a 5/16” nut driver for the hex head, screw into the hole by tapping threads until the head of the screw is tight against the surface of the material being fastened.
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: Bob Carlisle, President Concrete Fastening Systems, Inc