| Advanced Plumbing |
| All-Pro Plumbing Iowa, LLC |
| BMC Plumbing
|
| Connected Electric LLC |
| Cost Reduction Technologies LLC |
| D/R Electric Inc. |
| Durlam Electric, Inc. |
| Emory Dry Ice |
| Empire Power and Controls |
| Gibbar Electric |
| Gorsh Electric |
| Greg Wirth Electric, LLC |
| Hanley Electric & Pump, Inc. |
| John's Electric & Technical Services |
| Kline Sewer & Drain LLC |
Larry Den Herder - Life Member
|
| McGrath Fleet & Commercial |
| Pattison Sand Company LLC |
| Schadl Incorporated DBA Mr. Rooter Plumbing |
| Setpoint Mechanical Services |
| Sioux City Electric Co., LLC |
| University of Iowa |
| VP Plumbing |
| West Bank
|