Learn About Our Partners


Partnerships form the very foundation of our success in the industry. We join forces with companies that are innovative, reliable, and whose products have stood the test of time.

Each of our industry partners provide materials manufactured according to national building code and engineering specifications. They are the premier choice in all metal and wood-steel buildings. From walls and roofs, to HVAC and other accessories they have you covered.

Our partnerships with these premier manufacturers is yet another reason why Principal Builders is your total building solution.

Founded in 1987 in Albion, Nebraska, Sentinel Building Systems has grown from a one-man operation selling Quonset buildings over the telephone to a company that today is widely recognized as one of the premier providers of high quality all-steel and wood-steel buildings in the U.S.

Sentinel buildings are designed and fabricated according to AISI and AISC specifications, and the company closely follows guidelines provided by the Metal Building Systems Manual which outlines recommended industry practices from building sales through the entire erection process. Additionally, Sentinel engineers are registered professionals and Sentinel welders are AWS certified.

Energy Panel Structures was established in 1981 as a wholly owned subsidiary of the MacArthur Company of St. Paul, MN. MacArthur Company, was established in 1913 as a small manufacturer of pipe insulation and is a private firm with a 4A1 Dun & Bradstreet rating. They are now the number one choice for virtually all insulations and accessories from pipes to HVAC to roofing products with 20 warehouses throughout the western United States.

Energy Panel Structures was started in Albert Lea, MN. After three expansions the company moved in 1988 to Graettinger, IA to a new 40,000 square foot plant designed specifically for the manufacture of insulated panels. Since the move to Graettinger, EPS has expanded three times, adding 3,000 square feet for a door manufacturing facility and another 7,000 square feet to increase the finished goods storage capacity. Our latest expansion of 30,000 square feet to our main manufacturing space brings the total facility to 110,000 square feet on an 8-acre tract.

Logan Contractors Supply is a family owned one-stop shop for all the needs of today’s contractor. Whether it be paving, patching, commercial, repair, decorative, or general flatwork your partners at Logan have the materials, supplies, equipment, knowledge & expertise to help you get the job & get it done right.

Logan Contractors Supply takes great pride in maintaining & selling used equipment at affordable prices. We will provide specifications on all of our used equipment before any purchase is made. Quality products presented with financing packages & service programs to fit the equipment.


From concrete to completion, our partners provide foundational support and service.