Roofing Guide: TPO vs PVC

Do you have a low slope or flat roof and need our Roofing Guide: TPO vs PVC to help you decide on the type of roofing to use? Bob Harvey Roofing is here to help. With more than thirty years in the roofing industry working on commercial and residential buildings, we are happy to share our expertise. 

TPO (thermoplastic polyolefin) and PVC (polyvinyl chloride) are single-ply roofing membranes. They share the following characteristics:

• Energy efficient
• Similar installation and attachment methods 
• Fire resistant 
• Mold resistant
• Algae resistant
• Wind resistant.

PVC has a durability track record of more than thirty years and shows consistent material quality. TPO has been available for nearly twenty years, but the inconsistent manufacturing quality has been problematic. TPO is, however, cheaper than PVC, offers strong puncture resistance and is recyclable. 

PVC has excellent chemical resistance and is ideal to use in commercial buildings exposed to grease, fumes, oil and other chemical materials.

Cost

When it comes to cost, TPO and PVC compare well, but TPO is cheaper per square foot. TPO has not been on the market as long as PVC, so select the most affordable TPO roofing membrane from a reputable manufacturer. Include the following when you start costing for your low slope or flat roof:

• Membranes: various thicknesses and roll widths are available, impacting cost per square foot.
• Insulation: it can sometimes be more expensive than the membrane.
• Flashings, fascia’s etc.: are standard items acceptable or does the project require custom fabricated materials?
• Accessories such as guttering and skylights: rainfall patterns and building design guides the accessories required.
• Attachment system (ballast, fasten, glue): ballasting uses rocks or pavers to weigh the roof down, otherwise it is screwed or glued to the underlayment.
• Installation: some manufacturers insist that only authorized contractors install the PVC or TPO roofing.
• Long-term maintenance: a professional roofer must do the maintenance. 
• Tear-off: TPO and PVC roofing can be installed over an existing roof, but if the old roof must be removed, there is a cost attached to it. 
• Landfill costs: materials must be taken for recycling or to the landfill in the event of a tear-off.   
• Inspections: commercial buildings require more regular inspections by law than residential buildings.

Industry standards

Before committing to roofing material, investigate the standards of both the manufacturer and product. Whether you choose PVC or TPO roofing materials, both must at a minimum fulfill the requirements set by the American Society for Testing and Materials (ASTM) and be ENERGY STAR® qualified. 

Johns Mansville indicates that their fifty-millimeter PVC membrane meets the requirements of ASTM D 4434, Type II as does Duro-Last with their sixty-millimeter membrane. 

If you are committed to sustainability, look out for products that will receive a credit from the U.S. Green Building Council Leadership in Energy and Environmental Design (LEED). According to Duro-Last, their white, sixty-millimeter roofing membrane equals one credit with this organization. 

Energy efficiency 

Energy efficiency is another feature of the Roofing Guide: TPO vs PVC. Available in white and other light colors, TPO and PVC roofing materials have reflective properties that are ultraviolet (UV) resistant and deflect heat away from the roof. It helps keep the building cool and saves on air conditioning costs. 

Many TPO  and PVC roofing material manufacturers are Energy Star certified with the U.S. Department of Energy (DOE) and registered with the Cool Roof Rating Council (CRRC) in its Product Directory. If you live in an area with consistently high temperatures, TPO roofing does not stand up well to extreme heat, so PVC roofing is a better choice.      

Bob Harvey Roofing is a professional roofing contractor in Layton, Utah. Licensed and fully insured, Bob Harvey and his team provide roofing services for commercial and residential properties. Have you read the Roofing Guide: TPO vs PVC and made a choice? Contact Bob Harvey Roofing today.