Why Commercial Roofing Is Different
Commercial buildings — warehouses, office buildings, strip malls, multi-family properties — typically have flat or low-slope roofs that require different materials and techniques than residential pitched roofs. In the Rockford area, the most common commercial roofing systems are TPO (Thermoplastic Polyolefin), EPDM (rubber membrane), modified bitumen, and built-up roofing (BUR).
TPO (Thermoplastic Polyolefin)
TPO has become the dominant flat roofing system for commercial buildings in the Loves Park and Rockford area over the past decade. It’s white (highly reflective — good for energy costs in Illinois summers), heat-welded at seams (no adhesive to fail), and available in a range of thicknesses (45 mil is standard, 60 mil for higher-traffic roofs).
Installed cost in Rockford area: $5.50–$9.00 per sq ft depending on thickness, deck condition, and access.
EPDM (Rubber Membrane)
EPDM has been around longer than TPO and has a proven track record. It’s black (absorbs heat — can increase summer cooling costs unless covered with a coating), and seams are either adhered or tape-sealed. It’s particularly common on older commercial buildings in downtown Rockford and Loves Park industrial corridors.
Installed cost: $4.50–$7.50 per sq ft. Often the lowest-cost option for re-roofing when the existing EPDM can be recovered over.
Modified Bitumen
Modified bitumen (mod bit) is a multi-ply system common on older commercial buildings and on low-slope sections of larger commercial roofs. It’s durable but labor-intensive to install, and the torch-down application requires an experienced crew. Well-installed mod bit lasts 20+ years.
Installed cost: $5.00–$8.00 per sq ft.
Key Questions for Commercial Roofing in Rockford
- Can the existing roof be recovered (new membrane over old), or does it need a full tear-off? A core sample or probe tells you if the deck is wet.
- What drainage does the roof have? Improper drainage is the #1 cause of premature commercial roof failure in the Midwest.
- Is the contractor certified by the membrane manufacturer? Manufacturer warranties on commercial systems typically require a certified applicator.
Juno Construction handles commercial roofing in Loves Park, Rockford, and across Winnebago County. We install TPO, EPDM, and modified bitumen systems and work with property managers, business owners, and general contractors. Call us at (815) 721-7016 or see our commercial services page.