How to Choose and Use Concrete Fasteners (page 2 of 2)

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Choose the Right Fastener

Hammer-Set Anchors
The best feature of hammer-set anchors is that they’re quick to install. You don’t have nuts and washers to fuss with; just drill the hole to the right depth and hammer it home. These are great for hanging 3/4-in. furring strips and metal brackets and straps.

BEST USES: Concrete, concrete block, mortar and brick.

COST: 50¢ apiece (no screws to buy).

HOW TO USE: Hold your wood or other material in position and drill through it into the concrete to the correct depth. Slip in the anchor. To finish the job, strike the exposed pin with the hammer and drive it in.

DRAWBACKS: Once you anchor hammer-set fasteners, there’s no easy way to remove them without destroying the material or the fastener. If the fastener works loose, leave it in place and drill another hole. Don’t use hammer-set fasteners in crumbly concrete or mortar. Use a plastic anchor instead.

MEDIUM-DUTY
Sleeve anchors
These anchors are available in several sizes and will hold up to 200 lbs. The sleeves pinch the sides of the predrilled hole and get tighter as you tighten the screw or bolt.

BEST USES: Concrete, concrete block, mortar and brick.

COST: $1.25.

HOW TO USE: First, drill the proper size pilot hole (3/8-in., 1/2-in., etc.) through the wood or metal and into the concrete. Slip the sleeve anchor into the hole. Hold the object you’re fastening firmly against the wall because the anchor will draw it only slightly tighter as you tighten the screw or nut. Tighten the fastener until it’s secure.

DRAWBACKS: If you overtighten the nut, the fastener will break or break the concrete around the hole. If this fastener fails, you’ll need to drill another hole a few inches away and try again.

Concrete Screws
Using concrete screws is the fastest method for attaching furring strips, windows and doors, conduit clamps and electrical boxes. Drill the special-size pilot hole (see package for exact bit size) and drive the concrete screw’s super-hard, large profile threads into the concrete with a power screwdriver. Buy 3/16-in. dia. screws for lighter-duty and 1/4-in. dia. screws for heavier jobs. The beauty of this fastener is that if the piece needs to be removed, you can just back the screw out. They’re available in hex or Phillips drive heads.

BEST USES: Concrete and concrete block.

COST: 20¢ to 30¢ each (cheaper in bulk).

HOW TO USE: Use a special bit in your hammer drill to drill a pilot hole through the workpiece (if it’s wood) and right into the concrete. Drive the screw with a power screwdriver. Hex heads are easier to drive but the heads will protrude slightly above the surface after tightening.

DRAWBACKS: Not good for crumbly concrete or mortar. Keep some extra screw drive tips around; the screws are so hard that screw tips break often.

HEAVY-DUTY
Sleeve Anchors

These anchors in the large 3/8-in. to 1/2-in. dia. versions are perfect for anchoring heavy, weight-bearing framing members such as deck ledger boards.

BEST USES: Concrete and concrete block.

COST: $1 to $2 each.

HOW TO USE: Drill right through the wood and into the concrete with a masonry bit and hammer drill. Use a depth stop to get the correct depth and then blow the dust out of the hole with a turkey baster (don’t use your breath, because the dust will blow back in your face). Push the anchor into the hole and tighten the nut and washer to wedge the backside of the fastener against the concrete. Don’t overtighten. Try to get the anchor into the solid portion of the concrete block for added security and strength.

DRAWBACKS: Overtightening can cause them to break free. Use a hand wrench like a socket and crank them tight. Don’t torque them like a lug nut on a car wheel. If the fastener fails, drill another hole a few inches away.

Wedge Anchors

These are extremely strong anchors for attaching framing members to solid concrete. They come in a variety of lengths and from 1/4 in. to 1 in. in diameter.

BEST USES: Concrete and stone.

COST: $1.50 to $3 each.

HOW TO USE: Drill a hole the size of the anchor through the wood and into the concrete. Thread the nut on a few turns and tap it into place with a hammer. Be sure the washer is in place and tighten the nut with a wrench.

DRAWBACKS: Permanent. Once they’re in, you can’t get them out.