What is anchor bolt in construction?

On most commercial jobs the steel fabricator supplies the anchor bolts as part of the division 5 package, because they are detailed on the steel shop drawings, but the concrete trade physically sets them in the footings and piers before the pour. Templates, layout, and setting labor frequently appear in neither sub's quote, so scope it explicitly at buyout and name who furnishes and who installs in both subcontracts.

The grade is the minimum yield strength of the rod in ksi: 36, 55, or 105. Grade 36 covers most gravity columns, while grades 55 and 105 show up at braced frames, moment frames, and columns with high uplift or overturning loads. Grade 55 is often specified with the S1 weldability supplement so field fixes can be welded, and the cost difference per rod between grades is real, so check the grade on the anchor bolt schedule before pricing.

Anchor bolt placement tolerances are tight, and a bolt group that misses them means the column baseplate will not land on its pattern. Common fixes, all of which need the engineer's approval, include slotting or oversizing the baseplate holes with heavy plate washers, cold bending small misalignments, or core drilling and installing epoxy anchors. Every fix costs money and erection time, which is why surveyed layout and rigid templates are worth carrying in the estimate.