Builders frequently use concrete anchors to attach wooden components, such as ledgers and sill plates, to concrete surfaces. Although there are many varieties of concrete anchors, the wedge anchor is relatively inexpensive, easy to install and suitable for a wide range of applications, including bearing heavy loads. To determine an anchor's load-bearing capabilities, consult the anchor's packaging; most manufacturers provide recommendations regarding application and acceptable loads.
Things You'll Need
- Tape measure
- Comination hammer drill
- Wood bit
- Masonry bit
- Electrical tape
- Air compressor or brush
- Concrete wedge anchors with corresponding washers and nuts
- Scrap wood
- Hammer or mini sledge
- Adjustable wrench
Mark the location of the bolt holes on the wood's surface with a pencil and a tape measure. Attach a wood bit to the combination hammer drill and set the drill the driver or drill setting. Use the wood bit to drill through each bolt hole mark. Hold the wood against the concrete surface and position the wood in the desired, final location.
Draw the pencil along the top or bottom edge of the wood to mark the wood's vertical and horizontal location on the concrete surface. While holding the wood in position, insert the pencil through each of the wood's bolt holes and use the pencil to mark the location of the each bolt hole's center on the concrete. Remove the wood from the concrete surface.
Attach a masonry bit to the combination hammer drill and switch the drill to the hammer setting. Wrap electrical tape around the shaft of the drill bit to indicate the depth of the bolt hole; remember that the bolt must protrude far enough above the concrete surface and through the wood to accommodate both a washer and nut. Drill into the concrete at each bolt hole mark until the electrical tape reaches the concrete's surface.
Clear concrete chunks and dust from the bolt holes by blowing air into the holes with an air compressors or cleaning the holes with a brush; concrete anchors often fail if bolt holes are filled with debris. Slip a washer onto each concrete wedge anchor's shank and thread a nut onto each anchor. Position the pre-drilled wood's holes over the holes in the concrete surface. While holding the wood in position, insert a wedge anchor, butt end first, through the wood's hole and into the concrete's hole.
Pound the tip of the anchor with a hammer or mini-sledge. If pounding deforms the anchor's tip, place a piece of scrap wood over the anchor's tip as you pound. Pound the anchor until its wedge expands and grips the hole's interior. Test the anchor by pulling the anchor's tip outward. Insert the remaining anchor or anchors and pound the anchors' tips to secure the anchors to the concrete.
Tighten the anchors' bolts by hand until the wood rests snug against the concrete. Use an adjustable wrench to fully tighten the anchors' bolts and secure the wood to the concrete surface.
Tips & Warnings
- Consult anchor packaging to determine proper drill bit sizes; anchors will not fit in or bind to improperly sized holes.
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