Which flat roof is best: TPO, EPDM or modified bitumen?
It depends on the building. TPO is a common choice for commercial roofs in Texas because it is white, reflective, heat-welded at the seams and usually the least expensive of the three per square foot. EPDM rubber costs about the same, absorbs more heat because it is black, and is easy to patch. Modified bitumen costs more and holds up best to foot traffic and grease. PVC is similar to TPO and is often used on restaurants and industrial buildings where chemicals reach the roof.
TPO and PVC Single-Ply Roofs
TPO and PVC are single-ply membranes rolled out across the roof and heat-welded at the seams. TPO is one of the fastest growing commercial roofing products because it is reflective, energy efficient and resistant to ultraviolet light and ozone. PVC costs more and adds resistance to grease, chemicals and industrial pollutants.
Both typically last fifteen to twenty years in Texas. Most problems occur at seams, curbs, drains and edges, so careful installation at those points is important.
EPDM Rubber Roofs
EPDM is a synthetic rubber membrane installed in large sheets that are glued or mechanically fastened, with taped seams. It resists ultraviolet light, ozone and severe weather, and it is easy to patch. Because it is black, it absorbs more heat than a white roof.
Modified Bitumen Roofs
Modified bitumen is an asphalt roofing material reinforced with polymers and installed in two or three layers, either torched down or applied with adhesive. It costs more than single-ply membranes and holds up well to foot traffic, making it a good fit for roofs with equipment or regular maintenance traffic.
Choosing the Right System
Consider how much foot traffic and equipment the roof has, whether grease or chemicals reach it, how much the building is cooled in summer, and what roofing system is already in place. GLC Roofing offers free commercial roof inspections and can help you choose the system that fits your building and your budget.
Related Questions
What does a commercial flat roof cost?
Installed single-ply roofing has generally ranged from about $6 to $10 per square foot in North Texas, depending on insulation and details. Modified bitumen costs a little more, and removing wet insulation adds to the cost. Commercial roof inspections are free.
Can a flat roof be coated instead of replaced?
Sometimes. A roof coating over a sound membrane can extend its life. A coating over wet insulation or failed seams will not last. An inspection will show which applies to your roof.
How long do flat roofs last?
TPO typically lasts fifteen to twenty years, EPDM twenty years or more, modified bitumen fifteen to twenty years, and PVC twenty years or more. Ponding water and clogged drains shorten the life of any flat roof.
