wedge anchors

Wedge Anchors

Concrete Wedge Anchors are heavy-duty anchors used to secure materials and equipment to solid concrete masonry surfaces. They are extremely popular and are one of the strongest anchors for hold strength. Wedge anchors look and function like a sleeve anchor but have a much smaller sleeve near the anchor's bottom. This sleeve near the bottom is a mechanism that expands once installed and "wedges" itself into the concrete. Lengths on these anchors are measured from end-to-end.

Wedge Anchors are installed into drilled holes, exclusively in concrete. The non-threaded end is embedded into the hole and then struck to activate the expansion mechanism. This expansion gets fully utilized as the nut is tightened over the washer on the material being fastened. The majority of the wedge anchor remains embedded in the solid concrete material. The end that is sticking out is used to secure workpieces to the concrete.

*Note: Wedge Anchors are considered a permanent installation. The material or equipment may be removed, but the fastener cannot be removed from the concrete. The only way to remove a wedge anchor is to cut through it flush to the ground.

Wedge Anchors are commonly used on oil rigs, docks, piers, floors, walls, or slabs. They are available in Zinc Plated Steel, Hot Dip Galvanized Coating, and both 304 and 316 Stainless Steel grades. Wedge Anchors are available in 1/4"-20, 3/8"-16, 1/2"-13, 5/8"-11, 3/4"-10, 7/8"-9, and 1"-8 sizes, with the nut and washer included.

Minimum Embedment Depth For Wedge Anchors

Diameter 1/4" 5/16" 3/8" 1/2" 5/8" 3/4" 7/8" 1" 1-1/4"
Minimum Embedment Depth 1-1/8" 1-1/8" 1-1/2" 2-1/4" 2-3/4" 3-1/4" 3-7/8" 4-1/2" 5-1/2"

Acoustical Wedge Anchor Bolts

Masonry Acoustical Wedge Anchors are used to anchor and secure suspended wire to solid or hollow concrete, brick, and block masonry surfaces including concrete ceilings.

Acoustical Wedge Anchor Bolts are used to install or fasten wiring that needs to be suspended to concrete and other masonry materials. Acoustical Wedge Anchors are installed into drilled holes. The non-threaded end is embedded into the hole and then struck to activate the expansion mechanism on the material being fastened. The majority of the wedge anchor remains embedded in the solid masonry material being fastened to.

Wedge Anchor Installation Instructions

Installing a Wedge Anchor - Step 1

Drill A Hole Into Concrete and Insert The Wedge Anchor - The first step of wedge anchors installation is to insert the anchor into a pre-drilled hole (or drill the hole into the masonry material with a masonry drill bit). Make sure the hole is clear of debris. The hole should be the same diameter as the wedge anchor. The nut and washer should be removed before installation. The anchor should fit snuggly into the hole. Hit the top of the anchor with a hammer (on the unthreaded portion) until the desired embedment depth is reached.
Installing a Wedge Anchor - Step 2

Add the Material - The next step is to add the equipment or material being anchored to the concrete over the exposed threaded portion of the wedge anchor. Double check prior to installing the material that the anchor has reached at least the minimum embeddment length. Next add the washer and then the nut.
Installing a Wedge Anchor - Step 3

Tighten the Nut - This is the important part. Using a wrench or socket, tighten the nut. This pulls the threaded portion of the bolt up through the wedge mechanism at the bottom of the anchor, which expands and embeds into the concrete and anchors the material to the concrete.
Installing a Wedge Anchor - Step 4

Finished Application - After the nut is tightened and the wedge has embedded into the masonry surface, the material you are anchoring should have a tight fit and be resistant to pulling out of the initial hole. Wedge anchors provide one of the strongest holds of all masonry anchors and are used in a wide variety of applications.

How to Install Wedge Anchor Bolts

Wedge Anchor Installation Video
Wedge Anchor Installation Transcript

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Bob: Welcome back to Albany County Fasteners - Fasteners 101. Today we're going to be reviewing Wedge Anchors, so let's get started.

Zinc plated wedge anchors are used in interior applications and can be used on exterior applications. Hot dip galvanized wedge anchors are used for exterior applications. In fresh water, such as rain water, bay water, anything where you are using it in a non-salt water application. 304 Stainless is also used in fresh water. This will give you long lasting non-corrosive applications. So you would use stainless steel in an application where, you do not want to see any rust over a period of time or any surface corrosion.

316, 316 stainless is marked as 316. You'll find it marked on the nut. 316 Stainless. You'll find it on the washer, marked, as 316 stainless. And you'll see a marking on the bottom of a 316 stainless wedge anchor These wedge anchors can be used in saltwater applications. Such as docks, decks, anywhere you have, or a boardwalk; Anywhere you have a application where you are using salt water.

Okay, so we're going to prepare to install this half inch wedge anchor. We're going to take the nut off and the washer; we're going to use this blue tape as a marker to prevent from drilling through the concrete. I'm drilling into 8 into the concrete here so I have no worries, this is a two and three-quarter inch wedge anchor, so I have no worries about drilling through the concrete you never want to drill through the concrete so the bottom of the wedge anchor goes through the concrete. You always want to make sure you have enough thickness in concrete for the correct length of wedge anchor.

You want to have at least one inch sticking out of the top of the concrete, when you finish, so I'm going to take the wedge anchor and just put it up here and go to optimally 1 inch below and I'm going to put the tape where I want to stop from drilling. Stop the drill from continuing to drill it through the concrete if you drill the hole too deep it's not really going to hurt it if you were a little further let's say another half inch you just don't bang the wedge anchor too far down because once you push it down you will not, this piece down here creates the wedge once you put the wedge anchor into the hole and you pull up on it then wedges into the concrete preventing you from pulling the anchor out.

At that point you would have to use a Sawzall and cut it off to make it even with the concrete and then fill the hole push it down and fill the hole if you, you know, want to close up the hole. So now we're prepared and ready to drill a hole in the concrete and install the wedge anchor.

You just want to, tighten it to where it snugs up very tight. There you go, it is now that post base is now installed. Put the cover over it, put your post in, your deck is ready to go in place.

There you go, we've reviewed the proper installation for a wedge anchor. Along with proper materials to be used for your application.

FAQs

What are wedge anchors?

Wedge anchors are heavy duty anchors designed for use in solid concrete. They are very popular and boast the best holding values of any masonry anchor in concrete. Once installed, they cannot be removed.

What is a wedge anchor used for?

Concrete Wedge Anchors are used to anchor and secure materials and equipment to solid concrete masonry surfaces. While they could be used in other masonry materials, this is not recommended. They are designed to work best in solid concrete and other anchors may outperform them in other masonry materials, such as brick or block.

What is the difference between a wedge anchor and a sleeve anchor?

Different styles of anchors are made for different applications, and some are made to be versatile. Wedge anchors get their best and most consistent holding power and strength from being installed into solid concrete. Sleeve anchors are more versatile, being able to be installed into concrete, brick, or block. This comes at the cost of a weaker holding value compared to a more dedicated anchor like the wedge anchor.

Can wedge anchors be removed?

No. Like many other anchors, including sleeve anchors and hammer pin anchors, wedge anchors cannot be removed after installing. If they were removable, they would not be nearly as effective in securing heavy loads. If you need to "remove" a wedge anchor, your best bet would be to remove the nut and washer and tap the anchor beneath your work material's surface. You may need to cut off any protruding part of the anchor if it doesn't sit flush. This way, at least, the anchor is no longer sticking out.

How deep do you drill for wedge anchors?

The hole for a concrete wedge anchor should be drilled 1/2" deeper than the anchor will penetrate into the concrete, making sure that the minimum embedment requirements are met. You can refer to the chart below for minimum embedment requirements.

Minimum Embedment Depth For Wedge Anchors
Diameter 1/4" 5/16" 3/8" 1/2" 5/8" 3/4" 7/8" 1" 1-1/4"
Minimum Embedment Depth 1-1/8" 1-1/8" 1-1/2" 2-1/4" 2-3/4" 3-1/4" 3-7/8" 4-1/2" 5-1/2"

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