Exposed metal ceiling trusses over newly manufactured windows on the floor of a window production facility.

MI Windows and Doors Manufacturing Facility Expansion


Growing customer demand meant that MI Windows and Doors needed to expand their window production capacity. Gannett Fleming created a more efficient work environment to support production and employees. Careful construction staging and logistical planning for site access enabled the design team to meet the challenge of expanding an occupied structure while ensuring worker safety and minimizing the disruption of the production process at the existing facility. Because the project features new, large-scale manufacturing equipment, the team coordinated construction progress with equipment deliveries.

What We Did

A transformative expansion of a window and door manufacturing plant promises to bring more than 100 new jobs to a central Pennsylvania community and allows the facility to meet growing customer demand.

The MI Windows and Doors manufacturing facility provides high-quality windows and doors for customers across the U.S. By adding two new production lines, as well as new equipment and facilities that support operational improvements, the expansion will keep products moving and increase the plant’s production capacity to 40,000 windows per week.

The addition includes a 7,500-square-foot staging and inventory area and a 90,000-square-foot production line and shipping area to accommodate the high volume of windows. The project fully modernized the facility, offering production employees a state-of-the-art work environment and enhanced comfort and convenience. The project also includes renovations and additions to the administration and office areas, and new offices, break areas, and multi-use restrooms inside the addition.

Close collaboration with the client allowed the team to coordinate function and services needs for an efficient and effective manufacturing facility layout. Storm drainage improvements were also added to keep water from the factory from flooding a neighboring farm.

Key Features

  • Construction staging sequence designed to minimize disruption to ongoing production operations and ensure employee safety.
  • Parking lot expansion, upgraded lot lighting, and traffic improvements enhance safety and convenience for employees and visitors.


  • The layout design includes six new air rotation units to circulate air and provide comfort in both the facility and new large-volume warehouse production spaces.
  • The new addition to the existing primary production facility building features an open production space, break area, office/supervisor area, new maintenance area, and new restrooms.
  • Improved flow of production and shipping.


MI Windows and Doors, LLC


Gratz, Pa.


Design, Construction Services, Architectural Services

What are you looking for?
Privacy Preferences

When you visit our website, it may store information through your browser from specific services, usually in the form of cookies. Here you can change your Privacy preferences. It is worth noting that blocking some types of cookies may impact your experience on our website and the services we are able to offer.

Our website uses cookies, mainly from third-party services. Define your Privacy Preferences and/or agree to our use of cookies.