#153 – How to Remove Concrete Anchors: The Complete Guide

While some tried-and-true methods are still needed for removing concrete anchors, a new product vastly reduces the effort in many types – and breaks them off clean

Contractors of all kinds rely on concrete anchors to provide secure and permanent placement for large motors, pipes, structural framing, and a whole lot more. But when those anchors need to be removed, as they often do, the process can often be difficult and labor-intensive. And even then, they often don’t come off completely.

In this article, we explain how to remove concrete anchors, discussing anchors’ characteristics, the tools available for removal, and how removal approaches vary for different types of anchors.

Designed to permanently embed underground, concrete anchors fall into one of two broad categories

Concrete and masonry fasteners consist of a mixture of bolts, sleeves, screws, and other components designed to set permanently in concrete, brick, and other hard materials. Sometimes, this secure fit is provided by components that expand as the bolt is drilled or threaded into the concrete. Other anchors are held in place by powerful adhesives. While the amount of force these fasteners can withstand varies with their type, construction, and the characteristics of the concrete, all concrete anchors are designed to stay in place even when placed under a great deal of stress, making them difficult to remove.

Masonry workers categorize these fasteners as either male anchors or female anchors:

  • Female concrete anchors consist of an expanding sleeve or tube with female threads. Installers place this female-threaded component into a pre-drilled hole. Then, they force the expanding tube to widen within the hole. Some lock in place only with the use of a specialized setting tool, while others simply expand when joined with a male-threaded bolt, screw, or rod.
drop-in female anchors
The brass-colored components on these drop-in female anchors expand as the bolt tightens, securely gripping the surrounding concrete. Source: Wikipedia

• Male concrete anchors combine the anchoring component and the fastening rod, bolt, or pin into a single unit. Hammering the pin in or tightening a nut over the threaded rod causes the anchor to expand and lock in place.

wedge anchors
Tightening the nut on these wedge anchors causes the expanding clips to widen, forming a wedge. Source: Wikipedia.

Most female concrete anchors can be removed with simple tools, but male anchors can prove troublesome

From renovation to electrical work, a wide variety of projects sometimes entail the removal of anchor bolts. Warehouses, for example, often need to relocate pallet racks – secured by either wedge or strike anchors – to make the most of inventory space.

Modern warehouse
Countless concrete anchors support the racks used in modern warehousing. Source: Wikipedia

But very few concrete anchors can be completely removed without damaging the concrete. Instead, anchor bolt removal usually entails leaving some part of the anchor embedded in the surface, while the above-surface part of the anchor – be that a bolt, threaded rod, pinhead, or part of the anchor itself – is cut off or pulled out. By applying a concrete-patching solution, the remaining part of the anchor and the hole can be covered, leaving a flush surface.

Female concrete anchors are generally simpler to remove. Usually, a screwdriver, pipe wrench, or vise grips can unthread the protruding bolt, leaving the female anchor flush with the concrete. If needed, a hammer can be used to knock the anchoring tube below the floor, and in some cases these tubes can simply be pulled out of the hole entirely.

Male concrete anchors can be much more difficult to remove. If the hole beneath the anchor is deep enough, some anchors can simply be pounded into the ground. Others must be split with a hacksaw or cut-off wheel, leaving an above-ground nub. Generally, that nub can be flattened with a hammer, although some larger nubs may need to be leveled with a grinding wheel. Of course, this all requires a lot of effort.

These methods can work well for removing anchor bolts a few at a time, but contractors looking to remove tens or hundreds of bolts quickly find these methods way too slow and frustrating. And in some facilities, a hot work permit may be required due to the sparks generated by angle grinders or hacksaws, making a time-consuming task even more of a hassle.

Oregon-based Product Design Specialties has developed an effective, easy-to-use anchor bolt removal tool

In response to the shortcomings of traditional anchor bolt removal methods, Product Design Specialties, an Oregon-based manufacturer of ergonomic tools and hazard mitigation equipment, began developing a simple anchor bolt removal tool. Patrick O’Banion, Product Design Specialties’ founder, describes their origin:

“I first made this thing probably seven years ago. And the first one I made, I didn’t have the right equipment – it was expensive. So, I made it, and it worked well, but then I just hung it on my wall for probably about three or four years. Well, one of my other customers came over and asked if I had anything that could break off anchor bolts. He says ‘Man, we’ve got 500 of them that we need to break off. It’s gonna’ take us a week.’ So, I loaned it to him. Well, the next day by noon, they called me up and said ‘Hey, Pat. We’ll take two of them. And this other company’s needs two of them. How fast can you get them made?'”

Fire Alarm Bells

Soon after, Product Design Specialties secured the equipment needed to produce this new product – the Boltbreaker – at a much lower cost, quickly earning the business of a wide variety of contractors.

Boltbreaker provides one the simplest, safest, and quickest methods on the market for breaking off threaded rod. If something sticks out of concrete – whether it’s part of a concrete anchor or not – it can be cut and prepped for concrete patch in a fraction of the time used by other methods.

By sliding the Boltbreaker over a protruding bolt, rocking it back and forth once, and rotating in a circular motion, this device heats and weakens the molecules inside the bolt, causing it to snap off – cleanly. In fact, harder bolts, such as SAE Grade 8 carbon-alloy steel bolts, break off even more cleanly than lower-grade bolts.

Using carbon-steel tips designed to match the diameter of each anchor bolt – including 1/4″, 3/8″ 1/2″, 5/8″, and 3/4″ sizes – it removes concrete anchors at or below floor level, leaving the floor ready for concrete patching. Boltbreaker can remove everything from short nubs protruding above a nut to full-sized rods in excess of 20″ long. It requires no electricity, generates no dust, and produces no sparks, eliminating the need for hot work permits, as shown in the video below:

How to remove male concrete anchors by anchor type

If you want to remove most concrete anchors quickly and easily, buy a Boltbreaker. If you only have a few to remove and you want to do it the old-fashioned way – or it’s a type of bolt that requires a different process – let’s look at the methods of getting rid of these common male concrete anchors:

  • Wedge Anchors
  • Strike Anchors
  • Sleeve Anchors
  • Split Drive Anchors
  • Hammer Drive Anchors

Removing wedge anchors

The wedge anchor has a small expanding sleeve attached to one end of the anchor. Designed for use in solid concrete, they are widely used to secure light posts, ductwork, and pallet racks.

Wedge anchors can be removed from concrete in one of three ways:

  • If the hole beneath the anchor is deep enough, simply pound it into the concrete with a hammer
  • Use a saw or grinding wheel to cut the anchor off just above the surface, and pound the rest flat with a hammer
  • Or you can simply place the Boltbreaker over the protruding rod, rock back and forth, and rotate until the rod breaks off

Removing sleeve anchors and strike anchors

Strike anchors feature an expanding body with a threaded top and a pin used to expand the anchor in the concrete hole. Sleeve anchors, used with concrete, brick, or block, use a threaded rod, a nut, and an expanding sleeve to secure to concrete.

Sleeve anchor
A sleeve anchor. Source: Folkestone Fixings

Like other male anchors, sleeve anchors and strike anchors can’t be fully removed, although some sleeve anchors can simply be tapped below the surface of the concrete after removing the nut and washer. But the threaded rod protruding from a sleeve or strike anchor can be removed and patched by following these steps:

  1. Remove the nut and washer from the anchor.
  2. If the hole beneath the anchor is deep enough, simply pound it into the concrete with a hammer.
  3. Cut off the threaded, above-ground section of the anchor. If you have a Boltbreaker, slide it over the protrusion, rock back and forth once, and rotate until the bolt snaps off below the surface. Alternatively, cut through the bolt with a hacksaw or grinding wheel.
  4. If necessary, make the remaining nub flush with the surrounding concrete. Sleeve anchors can often be knocked deeper into the ground with a hammer. Hammer or grind any protruding rod as necessary.

Removing split drive anchors and hammer drive anchors

Hammer drive anchors feature a pin and sleeve designed for insertion in a pre-drilled hole. Hammering in the pin causes the sleeve to expand, trapping the anchor in the hole. The split drive anchor is a single-piece anchor with two pre-expanded halves that compress and then re-expand when hammered into a hole.

Hammer drive anchor
A hammer drive anchor. Source: Deelat Industrial via YouTube

When installed, these anchors leave only a flat head at the surface. Extraction methods for these hard-to-remove fasteners vary, but recommendations for removing hammer drive anchors and split-drive anchors include:

  • Pulling out the anchor with a flat prybar and hammer
  • Removing the head with a grinder, then flattening the protruding anchor
  • Chiseling under the head and pulling out the anchor

How to remove female concrete anchors by anchor type

While all female concrete anchors can easily be made flush with the surrounding concrete, most have an anchoring component that remains permanently embedded.

Machine screw anchors and drop-in anchors feature an expanding plug that locks in place using a specialized setting tool. Because the entire anchor sits below the surface, any bolts or threaded rods connected to them can simply be unthreaded and the anchor hole patched over. Neither a machine screw anchor nor a drop-in anchor can be removed without damaging the concrete.

Machine screw anchors
Machine screw anchors. Source: Eden Farms Online via Bonanza

Lag shield concrete anchors use a bolt and sleeve that insert in a hole. As the bolt threads into the lag shield, it expands, fastening it to the concrete. Lag shield concrete anchors may be the easiest anchor to remove: as the bolt is removed, the anchor may contract, allowing it to be pulled from the hole.

Specialty anchor bolt removal tools now available at QRFS

If you’re looking for a faster way to remove wedge anchors, sleeve anchors, or strike anchors from concrete, Product Design Specialties’ line of anchor bolt removal tools are now in stock at QRFS.

Available with an orange or yellow finish, each Boltbreaker includes two interchangeable carbon steel tips designed to cleanly break off 3/8″ or 1/2″ anchor bolts, metal rods, or rebar embedded in concrete. Tips for 1/4″, 5/8″, and 3/4″ bolts are available by special order.

This standard-sized Boltbreaker is 25″ long, providing the user with ample leverage and portability.

Boltbreaker can break off low-carbon, medium carbon, and medium carbon alloy steel bolts or rod, and it is available in three sizes:

  • Long (40″) for maximum leverage
  • Standard (25″) for a blend of leverage and portability
  • Mini (20″) for confined or otherwise compact spaces

Click here to view our selection of Boltbreakers.

Questions about how to remove concrete anchor bolts? Want to order a Boltbreaker with non-standard carbon-steel tips? Call us at +1 (888) 361-6662 or email support@qrfs.com.

This blog was originally posted at blog.qrfs.com. If this article helped you find a solution, check us out at Facebook.com/QuickResponseFireSupply or on Twitter @QuickResponseFS.

15 thoughts on “#153 – How to Remove Concrete Anchors: The Complete Guide”

  1. hiiii buddy….. I really like your post and i appreciate your work regarding this article.This article is so helpful for me and must say you did great work. i appreciate your work.

  2. It’s great to learn that a concrete-patching solution can cover any holes that are left from cutting the material. My wife and I are wanting to renovate our outdoor patio and we were wondering how we could cut some concrete. I’ll be sure to tell her that we should use a concrete-patching solution after cutting it.

  3. Thank you so much for your awesome post! Recently I was thinking about how to remove the concrete anchors of my concrete & driveways and I believe your post will help me a lot. No more confusion as it is informative and nicely described. Cheers!

  4. Thank you for your article! Very informative and hoping the Boltbreaker will help us remove at least the extra bolt sticking out from the walls!

  5. This is all well and good if you don’t want to reuse the hole where the Anchor Bolt is.
    I bought 14 Anchor Bolts from my local Building supplies and soon found out that they were totally useless.
    The bolt went into the drilled hole, but the wedge would not fix itself in the concrete. I tried everything to fix it but nothing has worked . Now I’m going to have to drill three hooles along side the bolt to extract it, then fill the thrree holes with Concrete Fix injection, before redrilling for a screw and rawl-plug. I have never had sucess with these bolts and have never had a problem with the old fashioned way.

    • Terry — if the top of it broke off and it is embedded into the concrete—and you can place a screw elsewhere—you may be able to just pound the screw farther into the concrete and patch over it. If you definitely need that screw out of there, there are some screw remover attachments that can be used with drills that may work. Best of luck!

  6. Hi,
    Are you able to accept a photo? I would like to send you a picture of a concrete needed rail post I would like to remove. Hope you have a solution.

    Thank you.

    • Ricardo — Our specialty is fire protection, and the bolt breaker enables fire protection contractors to do their work. Unfortunately, we aren’t your best resource otherwise. Best of luck with the project. Thank you.

  7. Needing some help. I’m working at a high school in SoCal where the owner’s rep. wants to remove sixty existing benches at the Boys and Girls locker rooms and replace with new pedestals and benches. The vendor who provided the new product didn’t realize that the existing benches were installed to last the test of time with what appear to be pipe spikes but without the internal threads. They’ve been there since the 1940s. Each pedestal (120 of them) has four of these anchors. It almost appears it would be easier to sawcut concrete around each pedestal. See attached photos and let me know if this boltbreaker tool will expedite removal. https://photos.app.goo.gl/w6AXz9qoBQgLBbTo9 I have not found photos of this anchor anywhere on the www.

    • Manuel — Unfortunately, it’s difficult for us to say from the pics — the boltbreaker may or may not be able to grab those. If it can grab, it would likely work — but we can’t say for sure without trying it. Apologies that we can’t make a clear judgment call from the images. But you can email support@qrfs.com if you want to send additional info (e.g., measurements) and have us look into this further. Thank you.

  8. I wanted to express my gratitude for your comprehensive guide on how to remove concrete anchors. This blog post has been incredibly helpful to me as I recently found myself in a renovating situation where I needed to remove concrete anchors but had no idea where to start. Your great instructions, along with the accompanying visuals, made the process much more manageable and less daunting. Already bought my replacement sleeve anchors now I just need some new tools. Thanks again!


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