Makers of Single-Ply Sheet
Carlisle SynTec and Versico sit in the same corporate family and make TPO, PVC and EPDM sheet. Holcim Elevate, the company that carries on the old Firestone Building Products line, is known for EPDM and TPO. Sika Sarnafil builds its reputation on welded thermoplastic sheet. Duro-Last cuts and welds PVC membrane to the roof's measurements in a factory before it ships.
Detail work matters most on large low-slope plants and warehouses like those in the Eastern Iowa Industrial Center, where long seams and many rooftop penetrations give a membrane plenty of places to fail.
Bitumen, Insulation and the Rest
GAF sells modified bitumen and single-ply under one name, along with polyiso insulation. Johns Manville makes TPO, PVC, built-up and insulation, a mix that suits the older roofs where somebody wants to keep a familiar system. Soprema brings modified bitumen and liquid-applied membranes to buildings with tight details and awkward penetrations.






