How To Hang Heavy Items On Concrete Walls

Concrete walls, such as those you find in a basement, are notoriously hard to anchor into because it's so difficult to drive fasteners into this hard, dense building material. While it's possible to drive special masonry nails into concrete, this takes some skill, and it's easy to break out a chunk of concrete in the process, so you have to start over someplace else. A better alternative is to drill a pilot hole and install a concrete screw or a heavier-duty anchor such as an expanding anchor. The key to success is drilling the right size of hole for the screw or anchor.

Before starting, you'll need suitable tools. Standard screws and nails won't cut it on concrete; instead you'll need concrete screws (sometimes called masonry screws). Concrete screws are made from harder steel than traditional screws and have threads that can cut through this dense material, though you still need a pilot hole. Look for screws rated for an object of the size and weight you are attempting to hang. They should be at least 1 1/2 inches long to ensure they are secured deeply into the wall to support your heavy objects.

If you are hanging items that exceed the weight limits for concrete screws, you'll need wedge anchors, the strongest type of expanding anchor. This steel anchor is tapped into a predrilled hole before a nut on the anchor is turned to expand it inside the hole, causing it to cling tightly inside the concrete. Avoid drilling a hole too large when using a wedge anchor or it may pull loose. After the anchor is secured, the nut and washer are used to fasten the item being hung.

While standard drill bits break when you use them on concrete, masonry drill bits have carbide tips that can hold up to the density of the concrete. These can be used with an ordinary drill, but even with a masonry drill bit, pushing the bit into concrete can require a lot of elbow grease and may burn out your drill motor prematurely. To make the job easier, consider buying or renting a hammer drill, as these vibrate the bit while drilling to help crush and remove concrete as you drill.

1. Select a Drill Bit

Choose a drill bit sized for the screw or anchor you will use. Pilot holes for concrete screws should be slightly smaller than the thread diameter of the screw; the threads will deform slightly as they dig into the concrete. For an expansion anchor, the pilot hole should be the same diameter as the anchor; this will allow you to drive in the anchor while ensuring the anchor can grab the concrete once it is expanded.

2. Drill the Pilot Hole

When operating the drill or hammer drill, wear goggles to protect your eyes from concrete dust. Drill the hole 1/2 inch deeper than the screw or anchor to provide enough space for the screw or anchor to avoid bottoming out. Hold the drill perpendicular to the wall and operate it at its lowest speed. Periodically remove dust from the hole with a can of compressed air.

3. Install the Anchor

To install an expanding anchor, use a hammer to drive the anchor into the hole until the washer rests on the concrete surface. Then use a ratchet wrench or open-end wrench to turn the nut clockwise to secure the anchor.

To install a concrete screw, use a hex-head nut driver or socket on a drill and drive it just like a standard wood screw. You can also use a screwdriver tip, but be careful not to screw the screw head; a nut driver applies more force without stripping. Leave the screw 1/4 to 1/2 inch out of the wall to provide a surface to support the object you are hanging.