UNI-Dome Multi Purpose Athletic/Sports and Recreational Facility

Scope of Work: Roof Replacement and ancillary improvements such as office remodeling, athletic floor replacement, sports lighting improvements and sound reinforcement.
Scope of Services: Design, Master Planning, and Project Coordination.

The hybrid roof system was developed to replace the existing 450 ft diameter air supported roof system at the University of Northern Iowa UNI-Dome. The hybrid system designed for this application utilizes the existing cables used for the air supported system as a secondary cable system linked by vertical members to the new crossed arch system. Stainless steel, standing seam roof panels supported by structural metal deck and bar joists form the skin of the peripheral area of the roof, covering 75% of the roof surface. The center 45,000 SF polygon is enclosed with an arch supported PTFE fabric tensile roof.

The roof scheme was adopted and developed for it's functionality and aesthetic value. The hybrid system uses the existing cable net, columns, and a reinforced concrete circumferential girder. The existing concrete compression ring is converted into a tension ring by prestressing the structure's periphery with a post tensioning system of tendons. The existing cable net, connected and stressed against the arches, gives the arches stability and allows them to be slender and relatively light weight. The center skylight was designed to provide nearly the same translucency for the new roof as the original roof it replaced. To aid in energy savings, the opaque roof area was designed with an insulated roof assembly.

Location: Cedar Falls, Iowa
Project Cost: $10 Million
Completion Date: 1999
Owner: University of Northern Iowa
Designers & Structural Engineers: DeNardis Associates, Light Structures with Horst Berger