Building Project Certainty with Modular E-Houses: A Copper Mining Success Story
When an industrial project encounters an unexpected setback, maintaining the construction schedule can become a significant challenge. For a new copper mining facility in the southwestern United States, a change in manufacturing partners threatened to disrupt progress on a critical component of the project: six modular electrical houses (e-houses). Interstates stepped in to take over the partially completed work, helping the client overcome equipment and design challenges while keeping the project on track for its planned start-up.
The project demonstrates how modular solutions, combined with technical expertise and flexible project execution, can help clients manage uncertainty and maintain progress even when circumstances change.
Taking Over a Project in Progress
The client was developing a new copper mining facility, where modular e-houses offered a practical approach to meeting the site's electrical infrastructure needs. Rather than constructing traditional electrical rooms on-site, the e-houses could be assembled, integrated, and tested in a controlled manufacturing environment before delivery. However, the project's original e-house manufacturer was unable to complete the work. With the construction schedule at risk, the client needed a new partner capable of taking over the existing scope and completing the six e-houses. "The biggest challenge was trying to pick up where the previous vendor had stopped and match what they were planning to do," says Stan Spaulding, Manufacturing Technical Sales Engineer at Interstates.
The transition presented several complications. Working together with the project’s engineering firm, Interstates inventoried and inspected previously ordered OEM equipment, reconciled labeling and documentation discrepancies, identified missing components, and reviewed hundreds of engineering files to determine the status of the equipment and remaining work.
Additional work included modifying equipment and rewiring 32 motor control center (MCC) buckets. Interstates restarted e-house manufacturing using the original designs, adapting them to its manufacturing methods and standards rather than reusing structures fabricated by the previous manufacturer. This approach allowed the team to build on the existing engineering work and previously ordered OEM equipment while addressing the project’s requirements.
Reducing On-Site Challenges Through Off-Site Integration
With multiple activities taking place simultaneously, congestion on-site was a major concern. Building and integrating the e-houses off-site allowed electrical infrastructure work to progress while crews continued preparing the mining facility for installation. This parallel approach reduced the amount of work required on-site, helping minimize congestion, trade stacking, and the associated safety issues. "The site was quite congested when we visited it prior to completion, so having the e-houses built and integrated off-site greatly reduced congestion and potential safety risks," says Spaulding.
Interstates also used REVIT modeling to account for potential clearance issues and design challenges before fabrication. A staggered delivery strategy enabled the team to prioritize the most critical e-houses, supporting the client's construction sequence while providing sufficient time for integration.
Testing Before Delivery to Reduce Project Risk
Quality assurance was another important advantage of the modular approach. Before shipment, all six e-houses underwent testing at Interstates' manufacturing facility, with a client representative present. This process allowed the team to identify and resolve issues before equipment arrived at the job site, where making corrections would have been more difficult.
The e-houses incorporated medium- and low-voltage switchgear, MCCs, transformers, variable frequency drives, HVAC systems, and other electrical and control components. Equipment layouts were designed to provide accessibility for maintenance, while HVAC systems were tailored to the heat loads within each e-house. These design considerations support long-term equipment reliability and maintenance efficiency, extending the benefits of modular construction beyond installation and start-up.
Delivering Greater Certainty
Despite inheriting a challenging project, Interstates successfully delivered all six e-houses, helping the client maintain its planned start-up timeline. The client expressed appreciation for the team's ability to take over the work and navigate the unexpected complications.
For Spaulding, the project reinforced one of the greatest advantages of modular construction: the ability to maintain progress on critical electrical infrastructure while other construction activities continue.
For clients managing complex industrial projects, modular e-houses offer more than an alternative construction method. By shifting work into a controlled environment, coordinating delivery with site needs, and resolving potential issues before installation, modular solutions can help reduce uncertainty and provide greater confidence in project schedules, safety, quality, and long-term performance.