I have a deep dark confession: I like to have things fastened to concrete. It's a strange addiction. I started doing this in college. There are many types of concrete anchors available, but I skipped the small plastic anchors entirely and went straight for the heavy ones. A 1/2-inch or larger lead shield bolts the multi-ton outdoor sculpture to the concrete pad. Soon after, I switched to sleeve anchors. I finally turned to wedge anchors. Redheads to you people in the know. I'm not proud of it. I've tried to break the habit, but I've stuck with it for 35 years. I can't stop. It's just so much fun — as long as you do it the right way.
If you use concrete anchors in the wrong way, you will be unbelievably frustrated. It could cause you to inflict serious bodily harm on your power tools (and probably want to throw them in the nearest lake while uttering lots of profanity). Each anchor is installed using its own unique method, and each has its own quirks. This can lead to frustration if you don't know which to use in which situation. Hope this article clears up any confusion.
Table of contents
- Types of Concrete Anchors
- Various concrete anchor bolt installation tools
- Summarize the types and usage methods of concrete anchor bolts
On the average construction site, you can find dozens of types of concrete anchors. I use several on a regular basis.
The strongest anchoring systems use resin-based anchors, which you install with a two-part epoxy. They are most commonly found in industrial and commercial settings and are too expensive or specialized for everyday use unless specified by an architect or engineer.
Some anchors have bolt heads that snap off at a predetermined torque level. They leave the bolt and flange to indicate the exact torque to use to tighten the anchor. These are also very expensive and should only be used for projects that must have extremely tight tolerances and absolute safety. Think long-span bridges or nuclear power plants.
Those of us who don't work for companies that pay $600 for a toilet seat typically use the type of concrete anchor shown here:
Wedge and Sleeve Anchors
Wedge anchors and sleeve anchors are both excellent types of concrete anchors that can hold significant weight. They provide strength for pull-out and shear forces. Try to avoid getting within 3 inches of the concrete edge due to the shot/wedging force they exert on the concrete. If you do this, you risk breaking a large board apart. Of the two types of anchors, wedge anchors provide the most strength – and are my personal favorite of all the anchors to use.
How to Install Wedge and Sleeve Concrete Anchor – Drilling
You can install wedge and sleeve anchors in the same way. Use a hammer or rotary hammer drill to drill the appropriate size hole and insert the anchor. Hit it in with a hammer. More on that below. The bore size is listed on the packaging, usually on the anchor itself. You must drill the hole at least 1/4 inch deeper than the anchor.
I recently wrote an article on how to drill through concrete. Also, if you're not familiar with the difference between rotary and rotary hammers, you might also want to read that article. Both are essential tools for specific jobs.
driving at anchor
Once the holes are drilled and the anchors are inserted into place, use a hammer or small sledgehammer to insert the anchors into the remaining locations, depending on the size of anchor you are using. Be very careful here. Note the photos below. There are two types of concrete wedge anchors and sleeve anchors. Good premium brand bolts have extra metal on top so they don't distort the threads when they're hammered in. If you're using a cheap anchor, back off the nut so you're not hammering the end bolt of the bolt. You want to hit the nut with a hammer and it will protect the threads (see photo on far right). Do not use excessive force under any circumstances.
You cannot remove wedge or casing anchors. Instead, you'll need to use a grinder or reciprocating saw to cut them away. For the Florida Outdoor Sculpture Competition in Lakeland, we have a new sculpture every year. Each sculpture is secured to concrete pads using wedge anchors. Instead of cutting them out, we actually drilled all the way through the 6" thick concrete pad to install the new sculpture.
Set concrete anchors and tighten nuts
The following year, after removing the sculpture that was about to be removed, we simply hammered the protruding anchors flush with the concrete surface. The mats were immediately available for us to install the new sculpture. Drill all the way through the pad to let the water flow through. Otherwise, the water in the hole will freeze and expand, causing the gasket to crack.
After installing the concrete anchors, tighten the nuts. Though you can use a socket set or a ratcheting open end wrench to get into tight spaces. To save even more time, especially when installing anchors with larger 3/4-inch or 1 1/8-inch bolt heads, invest in a cordless impact wrench. This really speeds up the process of tightening the concrete anchors. If you don't know the difference between an impact driver and an impact wrench, check out the video we made on the subject.
Large Diameter Concrete Anchor
Large diameter concrete anchors, including the Tapcon brand heavy-duty anchors, offer several advantages over other types of concrete anchors. In particular, they can be removed but not reused. However, once removed, you cannot reuse the hole. I've reused Tapcon concrete screws in non-critical indoor workloads, provided it goes into a newly drilled hole.
Another advantage of large diameter concrete anchors is that they do not expand and therefore stay closer to the concrete edge than wedge anchors.
Tapcon claims their large diameter concrete anchors are 20% stronger than wedge or sleeve anchors. Of course they installed very quickly. You won't be able to install them with hand tools (maybe hulk can). After drilling the proper size holes, install these large concrete anchors using an impact wrench.
Hysteresis shield (lead shield) and plastic anchor
Lag shields (often called lead shields) work the same way as plastic anchors. You drill the correct size hole, insert the anchor, and drive in the screw. This expands the metal or plastic, wedging it into place. Use them for the lightest anchors. This goes double for plastic anchors – we don't recommend them for concrete where higher pull-out strength is required. Plastic concrete anchors are good for lightweight objects—maybe 30 to 50 pounds, depending on the size of the anchor.
Lead guards, while useful, fell out of fashion due to the convenience of wedge and sleeve anchors. The latter offer stronger support and most people find they are quicker to install and use. However, lead shielding does have a unique trick. You should be using lag bolts with lead shielding. However, you can also use screw eyes (screw eye bolts) that have the same thread as the lag. Lead shields are the only concrete anchors that allow this. When it gets really tight, use a construction screwdriver to turn the screw eye.
At the Polk Museum of Art, we have permanently placed lead shields in the brick courtyard. In case a hurricane hits, we can install large eyebolts in the ground and knock down the sculptures to get them ready for the storm.
Tapcon Concrete Screws
It is no exaggeration to say that Tapcons changed the world. The first art gallery I worked at had brick walls, and my job was to hang exhibits every month or two. Drilling and installing plastic anchors is such a huge pain. Back then I would die for Tapcons, especially mount kits like the one pictured below. The plastic anchors definitely didn't have any effect on the look of the wall after we removed the exhibit, all you saw were little colored circles on the wall.
Powder Actuated Fasteners
Powder actuated fasteners are sometimes called Ramsets, which is a name brand. They are unique among anchors because they do not require a hole to be drilled first. Instead, they used a .22 caliber low-velocity powder charge to drive specially hardened nails through wood or metal into concrete. While fast, they can damage the concrete around the nail, moving the board you're trying to attach to the nail. My personal preference is to use them in cinder block walls and wedge anchors in concrete.
Toggle Bolts – An Often Overlooked Concrete Anchor
When it comes to cinder blocks, one of the most commonly used cinder block anchors is the toggle bolt. They take advantage of the cavities in cinder blocks. Squeeze the anchor's wings together, folding them down to the smallest possible size. Drill a hole big enough for the wings to go through. Next, put the wings through the holes and into the hollow cavity where they will pop open. Pull back on the bolt so the wing catches and tightens the bolt. A toggle bolt is a very strong anchor. In the photo below, I replaced the bolt that came with it with an eyebolt so I could attach the rope to the anchor.
Basic Concrete Anchor Kit – Best Tapcons for 5/16" Anchor
- cordless hammer drill
- masonry bit
- Tapcon Drill or Tapcon Mounting Kit
- Small bulb or other method to blow or suck out the hole
- hammer
- adjustable wrench
- PPE (hearing protection, eye protection, and dust mask)
Mid Rise Concrete Anchor Kit – Best Tapcons for 1/2" Anchor
- cordless hammer
- masonry bit
- SDS Plus Tapcon Drill and Installation Kit
- dust collector
- hammer
- construction screwdriver
- Socket wrench or ratchet combination wrench
- PPE (hearing protection, eye protection, and dust mask)
Pro Concrete Anchor Mount Kit – Best Tapcons for 3/4" Anchor Bolts
- Electric hammer drill with built-in HEPA dust removal device
- SDS Plus Drill
- SDS Plus Tapcon Bit and Mounting Kit (not shown)
- HEPA dust collector (not shown)
- 3 or 4 pound construction hammer
- construction screwdriver
- Impact wrench with impact socket and construction socket handle
- If needed, clean the surface with a leaf blower after installation
- PPE (hearing protection, eye protection, and dust mask)
PPE – Personal Protective Equipment
eyes and ears. That used to be the mantra of every foreman when they saw an OSHA inspector coming. "Eyes and ears, kids!" means everyone needs to wear eye and hearing protection. Now, it's eye, ear and lung protection. This is especially true when using concrete that contains silica, a known carcinogen. In plain English: Concrete dust causes cancer.
We have several articles on this topic:
- OSHA Form 1 Compliance
- How to Buy a Dust Collector
- Permissible Exposure Limits for Silica Dust
Summarize the types and usage methods of concrete anchor bolts
I have shown you many types of concrete anchors. There are actually many more, including hammer anchors, adhesive anchors, and epoxy anchors. You'll find the ones in this article on most residential job sites. Larger commercial or industrial sites may introduce additional sites. I've used each of these over the years for a variety of reasons, and each has its place. All types of concrete anchors are very easy to install with the proper tools. have fun! I know I will.
