Masonry anchors are anchors used to fasten or attach an item to the masonry. Masonry anchors refer to anchors that are used in all types of masonry including concrete, brick and block or CMU. There are three basic types of masonry anchors:
- Expansion anchors such as the wedge anchor or sleeve anchor
- Threaded anchors such as the tapcon masonry screw
Expansion Masonry Anchors
Expansion masonry anchors are anchors that expand exerting force against the wall of the hole in the base material that they are installed in. The expansion masonry anchor is designed to go into a predrilled hole in the base material and, once expanded, will not come out.
Types of Masonry Expansion Anchors
There are two different types of expansion masonry anchors designed for different applications:
- Male masonry expansion anchors penetrate the base material and stick up from the surface.
- Female masonry expansion anchor sits flush with the base material and expands or complete the fastening by having some type of bolt inserted into them.
Different Masonry Expansion Anchors for Different Types of Masonry
Masonry anchors that expand are not all created equal. Some masonry anchors are designed to be used in a variety of masonry base material such as solid concrete, brick or block; while others can only be used in only solid concrete. The masonry anchors that are designed for use in solid concrete only will give more consistent holding values in concrete over other versatile masonry anchor that can be used in all three base materials.
- WEDGE ANCHORS: The wedge anchor is a male masonry expansion anchor designed for use in solid concrete. Diameters ranging from 1/4” to 1-1/4” and lengths for 1-3/4” to 12”, available in zinc plated carbon steel, as well as hot-dipped, galvanized, 303 stainless steel and 316 stainless steel.
- SLEEVE ANCHORS: The sleeve anchor is a male masonry expansion anchor that is designed to be installed into concrete, brick or block base material. The sleeve anchor is the most versatile masonry fastener not only because of the variety of masonry it can be used in but also due to the wide range of diameters from 1/4” to 3/4” and lengths from 5/8” to 6-1/4”. It comes in four head styles: acorn head, hex head, flat head and round head as well as zinc plated carbon steel and 304 stainless steel.
- Tapcon: The tapcon brand concrete screw is a threaded anchor that taps threads into the base material of brick, concrete or block. The tapcon concrete screw is a male anchor that comes in a wide range of diameters from 3/16” to 3/4” and in lengths from 1-3/4” long to 6” long. The head style is either a hex washer head or the flat phillips countersunk available in the standard blue Climaseal® coating or the 410 stainless steel that is also coated with a silver Climaseal®.
- Drop In Anchors: These are female expansion type anchors that can only be used in solid concrete. The expansion of the drop-in anchor is accomplished through use of a setting tool, with a different size setting tool used with each different diameter of drop-in anchor. The drop-in anchors come in five different diameters of 1/4”, 3/8”, 1/2”, 5/8” and 3/4”. Each diameter of drop-in anchor has only one length available. The drop-in anchor is available in the standard zinc coated carbon steel, 304 stainless steel and 316 stainless steel.
- Hammer Drive Anchors: The hammer drive anchor is a male fastener that can be used in concrete, brick or block as long as the brick and block are solid. Hammer drive anchors are expanded by a pin that is hammered into the anchor body expanding it against the walls of the base material. Hammer drive anchors come in two diameters of 3/16” and 1/4”. They are available in one head style called mushroom head, which is tamper-proof because once the pin is set in the anchor it cannot be removed. The length of the mushroom headed hammer drive anchors range from 3/4” to 3”.
- Lag Shield Anchors: Lag shields are a female type expansion anchor that require the use of a lag screw inserted into them for the lag shield to expand. Lag shields come in two lengths:a short lag shield or a long lag shield. The short lag shield is used in applications where the base material is very hard and the short lag shields are used in applications where the base material is softer. Both lengths of lag shields come in six diameters.
- Strike Anchors: Strike anchors are male type expansion anchors that are designed for use in solid concrete only. Strike anchors utilize a pin for expansion and also include a nut and washer for attaching the fixture to the concrete. Strike anchors come in diameters ranging from 1/4” to 3/4” with lengths from 1-3/4” to 6”. They are plated with a yellow zinc coating. The strike anchor is not available in either a stainless steel or hot-dipped galvanized. Once the pin is set, the anchor is designed not to go in or come out of the concrete.
- Split Drive Anchors: Split drive anchors are a male type anchor designed for use in concrete only. They are available in one diameter of 1/4” and in lengths ranging from 1-1/2” to 4”. Zinc plated carbon steel is the only material that they are made from. They are not available in either hot-dipped galvanized or stainless steel. The split drive anchor comes in a round headed or a flat countersunk head.
As with any anchoring project, it is important to keep safety in mind and follow instructions carefully. Always remember to wear safety goggles, handle all tools with extra care and follow all technical specifications. This article is meant to serve only as a basic explanation of concrete fasteners. Always refer to manufacturer's instructions or consult a contracting expert during any anchoring project.
Article Written By:
Mike Pistorino, Vice-President Operations
Concrete Fasteners, Inc. has over 40 years of experience selling concrete fasteners. We can ship out one box or a whole pallet of concrete anchors. Our products are of the highest quality... "your satisfaction is guaranteed". We ship all orders the same day the order is received.