Commercial Flat Roofing (TPO, EPDM, Modified Bitumen)

TPO single-ply

Thermoplastic polyolefin (TPO) is the dominant new-construction membrane on Denver-metro commercial roofs. White-surface reflectivity helps with cooling load, heat-welded seams produce a continuous waterproof plane, and 60-mil and 80-mil thicknesses are standard for hail-prone markets. Pro Shield installs mechanically attached, fully adhered, and ballasted assemblies depending on building height and substrate.

Common Pro Shield scopes: full tear-off and replacement of an aged ballasted EPDM or built-up roof with new mechanically attached or fully adhered TPO; recover over a sound existing roof where the deck and insulation are dry; and patch-and-seam repairs after a hail event.

EPDM rubber

Ethylene propylene diene monomer (EPDM) is the long-life rubber membrane on most older Denver commercial roofs. Standard thicknesses are 45-mil and 60-mil; 90-mil is used where hail exposure is severe. Pro Shield repairs seam separations, replaces failed pipe boots and curb flashing, and full-replaces aged ballasted or fully adhered EPDM with either new EPDM or a TPO conversion.

Modified bitumen

Modified bitumen (Mod-Bit) systems are torch-applied or cold-applied asphalt membranes layered with polyester or fiberglass reinforcement. They show up on older Denver commercial buildings and on some mixed-use infill. Pro Shield repairs blistering, alligatoring, and seam failures, and replaces failed assemblies with new SBS or APP-modified systems where appropriate.

Insulation, tapered systems, and code

A flat roof is the membrane plus the insulation plus the deck. We design tapered polyiso layouts to move ponding water to drains, specify code-compliant R-values for the IECC zone, and detail edge metal, parapet flashing, and curb terminations to the manufacturer's published specification so the system warranty stays enforceable.

Hail and wind on a flat roof

Hail damage on commercial flat roofs is often invisible from a parapet but obvious from a walk-the-deck inspection. Pro Shield documents fractures, slits, and bond-line failures to insurance-carrier standards and writes the scope with the same statute-and-code framework we use on residential claims (C.R.S. 10-2-417 on adjuster authority, IRC and IBC code references where applicable).