Tapcon and wedge anchors are pre-installed mechanical anchors that attach structural objects to concrete structures. However, the wedge anchor suits heavier-duty applications, vs the Tapcon anchor that typically serve lighter deployments. Another difference between them is in their fastening method. Tapcons are self-tapping screws that tap their own holes when being driven into a material. This is what enables them to fasten the object to the concrete. On the other hand, Wedge Anchors hold the object to the concrete with the aid of a sleeve.
In this article, you will learn about the applications of Tapcon and wedge anchors, their installation method, and precautions to take when using them.
Tapcon vs Wedge Anchor Applications
Both Tapcon and wedge anchors fall under the general classification of anchor bolts. These pre-installed mechanical anchors require drilling a hole in the concrete before insertion. The term ‘mechanical anchors’ suggests that friction is the binding force that holds the structures in place. Another type of pre-installed anchors is chemical anchors. These rely on chemical bonding to hold objects to concrete.
Tapcon Anchor Applications
The self-tapping nature of Tapcons makes them common in many applications. Deploying them is quick and flexible. Predominantly, their base material is carbon steel or stainless steel. The material chosen largely depends on their working environment. Often, manufacturers cover the screws with a blue rust-resistant coating. But they also come in white and stainless colors.
Common applications for Tapcon anchors are as follows:
- They are ideal when the object attached to the concrete is of relatively light weight, and is static. It is not advisable to deploy them with heavy objects or machinery that will exert dynamic forces.
- Tapcons suit indoor applications. However, screws with coatings, or those made with stainless steel, fit outdoor use.
- They offer the ability to provide flush finishes. This is key in applications where aesthetics is a requirement.
- Tapcon screws are a desirable option in temporary attachments because of their ease in installation.
Wedge Anchor Applications
Wedge anchors are popular because they offer significant holding strength. They consist of a bolt and flared base, that runs through a sleeve. Also, they have a nut at the end for tightening the adjoining materials. Some common uses of wedge anchors include:
- To fasten static loads to concrete. Although they are more robust than Tapcon anchors, they cannot offer sufficient support for objects that will exert vibrational or shock loads.
- Dry indoor environments permit the use of wedge anchors with zinc coating. Conversely, stainless steel suits outdoor applications where there is moisture.
- Wedge anchors cannot be removed without damaging the concrete. Thus, permanent or long-term fixtures suit them.
Tapcon vs Wedge Anchor Installation Method
Ease of installation is a major factor that drives the use of each of these types of anchoring fasteners.
Tapcon Anchor Installation Method
- Use the correct diameter of hole that matches the Tapcon screw diameter. Typically, a screw of ¼ inch pairs with a hole of 3/16 inch, and a 3/16 inch screw requires a 5/32 inch hole. Achieving the correct hole tolerance is critical to giving the anchor the appropriate holding strength.
- The length of the hole should be sufficient to avoid the bottoming out. Ideally, a minimum allowance of ½ inch should be at the bottom of the hole. In addition, the hole length should penetrate both materials sufficiently to ensure a firm hold.
- Before inserting the Tapcon screw, remove all debris and dust that came from the drilling process.
- A wire brush of the same diameter as the hole is ideal for cleaning. Otherwise, vacuum cleaning presents another option.
Insert and Drive
- With the hole clear of every debris, insert the screw.
- Drive the screw into the hole with a rotation drill. Use minimal pressure and torque.
- Turn the screw by hand for the last couple of revolutions. By doing this, you exert less torque and prevent the Tapcon screw from stripping the threads tapped into the base material.
- Never remove the screw and place it back into the same hole. This has an adverse effect on its holding strength.
- Use a shallower embedment if the base material is so hard that it causes the bit to wear out.
Wedge Anchor Installation Method
To install a Wedge Anchor, take the following steps:
- Drill a hole that is the same diameter as the bolt into both materials. The tolerance between the hole and anchor should be very tight. Because this is the basis of its holding strength.
- Clear out debris from the hole as much as possible.
- Insert the threaded bolt into the hole on the concrete. In some cases, it may have to be hammered in.
- Next, place the material you want to attach to the concrete on the exposed portion of the threaded bolt.
- Subsequently, put the nut on the bolt and tighten. This action begins to pull the anchor up. Consequently, the wedge skirt at the bottom of the bolt digs into the concrete. This gives the anchor a firmer grip on both structures.
- It is not advisable to use wedge anchors to fasten loads to block, brick, and granite. This is because these materials are inconsistent. In addition, they do not have proven holding strength. As a result, wedge anchors will not set properly when used on these materials.
- Do not use wedge anchors on green concrete (concrete less than 28 days old). This has a negative effect on the holding values.
- Avoid placing two wedge anchors close to each other. Also, do not place them near an unsupported edge. Else, the pressure exerted on the concrete by the anchor will be excessive, leading to damage.