October 18, 2021
How To Buy a Metal Building
This is Part 2 of a multi-part series on deciphering the anchor bolt drawings you will receive from Heritage when you order your custom-designed steel building. While it is not likely that you will be pouring your own concrete, a basic understanding of how to read these plans can potentially save you costly and time-consuming mistakes from mis-placed bolts. Please refer your concrete company to this series, or directly to your project consultant, if they have any questions about the plans or bolt placement.
Heritage does not supply anchor bolts. When your building is delivered, you will ideally have your foundation already poured and cured so that erection can begin immediately. Since the bolts are part of the foundation construction, it is the customer’s responsibility to purchase the proper quantity and sizes of bolts. For structural columns, Heritage does not recommend drilling expansion bolts into an already poured foundation; the best way to ensure maximum structural integrity of your steel building is to place the bolts as directed into the wet concrete and let it cure around them. The only anchor bolts that should be drilled in are those for walk door frames.
Note: An anchor bolt plan is not a substitution for a foundation design. It is provided to show the detailed placement and configuration of the bolts on which your columns will rest.
In the drawings you receive, there will be three pages pertaining to anchor bolts. You should provide copies of those pages to your concrete company so they can use them as a map to place the bolts when pouring your foundation.
Part 2 covers page one of the three pages, shown here in its entirety:
Details about each of the three color-coded sections are below. The color coding is here for demonstrative purposes, so that you can see where each highlighted section is located within the page.
The sample building will require X-bracing, or cable bracing, on each wall. The diagram indicates where the X-bracing should be placed in the building. Make sure that you do not plan to place walk doors in these bays. If you see a conflict, notify your representative so they can revise the building design.
Walk doors are field located and self-framing, and as such are not indicated on this diagram. More information on walk doors is available in Part 1 of this series.
This sample building will utilize two different kinds of anchor bolts – 5/8” and 3/4″ diameters. The legend, to the left, lets you know on the plan diagram which diameter of bolts will go where in the building. In the sample building, the columns for the inside frame lines will be bolted with 3/4″ anchor bolts, and the two endwalls and two framed openings will use the 5/8” bolts. You can see on the diagram that twenty-four 3/4″ and thirty-two 5/8” bolts are needed. The Anchor Bolt Summary page, from Part 1, also lists how many of each size of bolts you will need.
This sample building uses three types of configurations for the structural columns. A indicates a single C-channel with a plate attached to the bottom, anchored by one 5/8” bolt on either side of the web. Configuration A occurs on each of the four corners of the building.
B indicates two C-channels placed back to back, with a plate attached to the bottom and anchored by four 5/8” bolts – two on each side of the web. Configuration B occurs four times, on each of the interior columns of the two endwalls.
C indicates an I-beam column with a plate attached to the bottom, anchored by four 3/4″ bolts – two on each side of the web. Configuration C occurs six times, on each of the two columns that make up the three interior frame lines.
This sample building has two identical framed openings for overhead doors – D and E. The columns that frame the doors are a single C-channel with a plate attached to the bottom. You will notice, however, that the bolt configuration for this column is different from Configuration A, which also use single Cs.
The diagram shows 5 different bolt configurations for the anchor bolts, labeled as A, B, C, D, and E. A, B, and C are the structural columns. D and E are the overhead door framed openings, and are the same.
Part 3 of this series will be available soon, and will go into detail about bolt configurations.