Installing walls or other components in a structure is easy when the concrete floors or walls are not yet fully set. In these situations, J-bolts or other types of anchors can be placed into the correct positions in the concrete when it is still wet, allowing the concrete to dry around the fastener for a very secure hold.
With already set and cured concrete or in concrete blocks or with brick construction, finding a way to use a fastener can be a daunting task. Through the use of concrete sleeve anchors even these hard, challenging materials will make ideal options for fastening wood, metal or other materials.
How They Work
In the most basic sense, concrete sleeve anchors work similar to a toggle or molly bolt, which is also sometimes called a hollow-wall anchor. However, since the concrete is not hollow, the movement of the sleeve is more restricted. At the same time, the strength and density of the concrete allow the sleeve of the bolt to catch and hold, providing a very secure attachment.
The first step will be to drill a hole the same diameter as the outside of the bolt and sleeve. The bolt and sleeve are then pushed or lightly tapped into the hole, and the nut is tightened. As this tightening occurs, the slightly larger end of the bolt pulls up through the sleeve, create a bulge in the sleeve that secures the fastener to the solid surface. This only works because the surface itself doesn’t give or move.
There are different lengths and diameters of concrete sleeve anchors available for all types of fastening needs. There are also several different head styles available, including the more traditional hex head as well as flat, round and acorn heads.
