Can You Use Concrete Anchors in Brick or Block? (What You Need to Know)

Introduction: The Danger of Treating Masonry Like Solid Concrete

Can you use concrete anchors in brick or block the same way you would in solid poured concrete? While the short answer is yes, the execution requires a completely different approach. Treat a hollow concrete masonry unit (CMU) or an old clay brick like a 4,000 PSI solid concrete slab, and you will almost certainly experience cracked masonry, spalling, and catastrophic anchor failure.

Solid poured concrete provides uniform, high-density substrate support. Brick and block, however, introduce voids, brittle face shells, and weak mortar joints into the equation. Understanding how expansion forces interact with these substrates is the difference between a fixture that holds a 500-pound load securely and one that rips out of the wall entirely. This guide breaks down the science of anchoring in brick and block, detailing which fasteners work, which ones will ruin your base material, and how to execute a professional-grade installation.

What You Are Drilling Into: Substrate Overview

Before selecting an anchor, you must evaluate the substrate. An anchor is only as strong as the base material it is embedded in. Solid concrete, hollow block, and brick behave completely differently under tension and shear loads.

Solid Poured Concrete: This is a dense, monolithic material typically rated between 3,000 and 5,000 PSI compressive strength. Because it lacks internal voids, it can handle aggressive outward expansion forces from heavy-duty anchors.
Concrete Block (CMU): Standard concrete blocks have a compressive strength hovering around 1,900 PSI. The structural integrity relies heavily on the web (the solid interior dividers) and the face shell, which is usually only 1.25 to 1.5 inches thick. Behind that face shell is empty space. High-expansion anchors will shatter this thin shell.
Brick: Whether extruded clay or molded shale, brick is incredibly dense but uniquely brittle. It is prone to splitting along internal stress lines if subjected to highly localized pressure. Furthermore, brick walls rely on mortar joints—a structurally inferior material typically rated for only 750 to 1,800 PSI (Type N or Type S mortar)—which cannot support heavy anchoring.

When to Use Specific Anchors in Brick or Block

Not all anchors are created equal. Knowing the various types of concrete anchors and how their specific expansion mechanics interact with your substrate is non-negotiable for professional results.

Wedge Anchors (Avoid in Brick and Block)

Wedge anchors are the industry standard for solid concrete, offering exceptional load ratings. However, you should almost never use a wedge anchor in hollow block or brick. Wedge anchors generate massive outward point-load pressure at the very bottom of the anchor. In a CMU face shell, this pressure will cause immediate blowout. In brick, it will split the masonry in half.

Sleeve Anchors (The Best All-Around Choice)

Sleeve anchors are the preferred expansion fastener for brick and block. Unlike wedge anchors, which expand at a single point, sleeve anchors feature a full-length steel jacket that expands uniformly along the entire shaft. This distributes the radial expansion force over a much larger surface area, greatly reducing the risk of cracking brittle substrates. They are ideal for medium-to-heavy loads like mounting handrails, ledger boards, or heavy electrical panels.

Concrete Screws / Tapcons (Ideal for Edge Work and Light Loads)

Masonry screws use a mechanical thread-cutting process rather than expansion force. Because they do not exert outward pressure on the surrounding material, they are perfect for use near the edge of a brick or into the web of a hollow block. They are best suited for light-to-medium shear loads, such as fastening furring strips, junction boxes, or rigid insulation.

Epoxy and Chemical Anchors (The Ultimate for Hollow Block)

For heavy, dynamic, or critical loads in hollow concrete block, chemical anchoring is the gold standard. This involves drilling a hole, inserting a specialized wire or plastic screen tube, injecting two-part epoxy (like Simpson Strong-Tie SET-3G), and inserting a threaded rod. The screen tube allows the epoxy to mushroom out behind the block’s face shell, creating a solid, high-strength keying effect without applying any expansion pressure to the block itself.

Key Differences in Holding Mechanics

The core difference between securing a fixture in poured concrete versus masonry lies in how the anchor generates holding power. Concrete anchors primarily rely on friction. They wedge themselves against the impenetrable walls of the drilled hole.

Brick and block cannot tolerate this friction-based approach when pushed to the extreme. Because they are softer and feature voids, contractors must rely on distribution (sleeve anchors), mechanical interlocking (masonry screws), or adhesion (epoxies). If you attempt a friction-heavy installation in block, the base material will fail long before the steel anchor shears.

Pro Tips for Drilling and Installation

Even the correct anchor will fail if the hole is drilled improperly. Precision is critical when working with hollow or brittle substrates.

Manage the Hammer Action: While solid concrete demands a heavy rotary hammer, brick and block require finesse. When deciding whether to use a hammer drill or a regular drill, err on the side of caution. Drill into brick using a standard rotary mode first to prevent cracking. For hollow block, turn the hammer mode off just before the bit punches through the face shell to prevent blowing out the back of the shell, which ruins your holding power.
Use the Exact Bit: Masonry screws and sleeve anchors have strict tolerance requirements. Always match the bit exactly to the manufacturer's spec, and ensure you are choosing the right drill bit for brick. Worn-out bits create undersized holes that bind anchors, while wobbling chucks create oversized holes that cause anchors to slip.
Clean the Hole: Masonry dust left in the hole acts like a lubricant, destroying friction and preventing epoxy from bonding. Use a wire brush and a blow pump or compressed air to clean out the hole completely before inserting any anchor.

Common Mistakes to Avoid

Professional contractors routinely fix masonry damage caused by poor DIY anchor installations. Avoid these frequent missteps to ensure a permanent hold.

Drilling into the Mortar Joint: Homeowners often drill into the mortar because it is softer and easier to penetrate. This is a severe error. Mortar is an adhesive, not a structural substrate. It has low compressive strength and will crumble under heavy loads. Always anchor directly into the face of the brick or the solid web of a concrete block.
Ignoring Spacing Rules: Anchors placed too closely together overlap their stress cones, leading to catastrophic failure of the entire masonry section. Always verify the manufacturer's minimum spacing and edge distance requirements. As a general rule of thumb, anchors should be spaced at least ten anchor-diameters apart.
Over-Torquing Sleeve Anchors: Hollow block has a strict limit on inward crushing pressure. If you over-torque the nut on a sleeve anchor with an impact wrench, you risk crushing the face shell of the block inward. Always use a manual torque wrench to hit the exact foot-pounds specified on the anchor’s packaging.

Buying Advice: Contractor-Approved Solutions

When selecting anchors for your next project, stay away from generic, unrated hardware. Load ratings matter, and the quality of the steel and sleeve design dictates the safety of your installation.

For medium-duty brick and block work, the ITW Red Head Hex-Nut Sleeve Anchor is the industry standard. A 3/8-inch sleeve anchor offers excellent shear strength for ledger boards and heavy brackets. If you are comparing Tapcon masonry screws instead of traditional expansion bolts, authentic Tapcons (look for the blue Climaseal coating) are unbeatable for fast, edge-friendly installations. Stick to the 1/4-inch hex head variety for maximum torque transfer without stripping.

For chemical anchoring in hollow CMU blocks, Simpson Strong-Tie AT-XP or SET-3G epoxies paired with their Opti-Mesh screen tubes provide building-code-approved holding power that mechanical anchors simply cannot match in hollow substrates.

Conclusion

Using concrete anchors in brick or block is entirely possible, but you must respect the physical limits of your base material. Solid poured concrete thrives under the aggressive expansion of wedge anchors, but brick and block require the distributed pressure of sleeve anchors, the mechanical threading of masonry screws, or the sheer holding power of epoxy. By selecting the right anchor, utilizing proper drilling techniques, and avoiding weak mortar joints, you can achieve secure, professional-grade fastenings in any masonry substrate without risking structural damage.