With today’s high energy costs, more businesses and homeowners are turning to thermoplastic polyolefin (TPO) roofing. This heat reflective and energy-efficient single-ply roofing membrane solution has become an increasingly popular alternative to the standard EPDM system due to its exceptional resistance to ultraviolet, ozone and chemical exposure.
TPO membranes are single-ply roof membranes constructed from ethylene propylene rubber. They are designed to combine the durability of rubber with the proven performance of hot-air weldable seams. They have been tested as having excellent resistance to ozone, are algae-resistant, environmentally friendly and safe to install. Seam strengths are reportedly 3 to 4 times those of EPDM’s adhesive and tape seams. TPO is highly resistant to tears, impacts, and punctures with good flexibility to allow for building movement.
Fully Adhered System
Fully Adhered TPO roofing system consists of standard or reinforced membrane that is adhered to the roof deck with bonding adhesive. The TPO membrane is installed over insulation which has been anchored to the roof deck with corrosion-resistant fasteners and plates. The TPO membrane is fully bonded to the insulation with bonding adhesive. Adjoining sheets are overlapped and hot-air welded making the system monolithic.
Ballasted System
Ballasted simply means the membrane is loose laid over the top of the roof, sealed at all penetrations and around the perimeter, and then a ballast is laid on top to hold it in place. Ballast usually consists of smooth, round, river rock 2″ – 3″ in diameter and is applied at a rate of 1,000 to 1,200 pounds per roof square (100 sq. ft.). Sometimes concrete pavers are used in their place. On average, ballast should equal 20 pounds per square foot.
Mechanically Attached System
Mechanically Attached Roofing System utilizes TPO membrane which is securely attached to the roof deck with plates and fasteners. During installation of the mechanically anchored system, the plates are placed in a specified pattern designated by the manufacturer. The plates are then anchored to the roof deck with fasteners. The Mechanically Attached System is designed for roofs which cannot carry the additional load of a ballasted system, where the roof deck is suitable for mechanical attachment.
