What Are TPO And EPDM Roofs?
TPO roofing is a single-ply roofing membrane composed of three layers: a TPO polymer base, a polyester-reinforced scrim, and a TPO compounded top ply. This thermoplastic roofing system is used to cover flat roofs on both residential and commercial properties. TPO stands for thermoplastic polyolefin and is made up of a blend of polypropylene and ethylene-propylene rubber. Introduced about 30 years ago, TPO roof systems have been continuously improved and are now one of the fastest-growing commercial roofing options on the market.
EPDM roofing, commonly known as a ‘rubber roof’, is an extremely durable synthetic rubber roofing membrane. EPDM stands for ethylene propylene diene monomer. This roofing system has been widely used in low-slope buildings in the United States and worldwide since its introduction in the 1960s. Over the years, numerous improvements have been made to enhance the performance of EPDM roof membranes, making them a reliable choice for many building owners.
By the end of this comparison, you’ll likely choose either TPO or EPDM for your roofing system. Regardless of which option you pick, be sure to request a quote from Best Roofing LA – we are widely considered one of the Best Los Angeles Roof Installation Companies by the locals.
TPO Roofing Vs. EPDM Roofing
The main difference between TPO roofing and EPDM roofing lies in their composition and performance characteristics.
TPO roofs are thermoplastic and belong to the single-ply roofing family, while EPDM is a synthetic rubber membrane. TPO roofing systems were introduced in the 1990s and continue to evolve, with manufacturers modifying their formulations to achieve better performance.
On the other hand, EPDM roofing has been around since the 1960s and is known for its exceptional elasticity, allowing it to expand and contract with temperature fluctuations and building movements.
1. Lifespan
The lifespan of a roof is a crucial factor to consider when choosing between TPO and EPDM roofing systems. TPO roofs typically last 15 to 20 years, with proper maintenance extending their lifespan up to 30 years. In contrast, EPDM roofs generally have a longer lifespan, ranging from 30 to 40 years. With excellent maintenance, some EPDM roofing installations can even last up to 50 years, making them a durable choice for long-term roofing solutions.
2. Cost
When comparing the cost of TPO roofing versus EPDM roofing, there are some differences to consider. TPO roof costs range from $3.5 to $10 per square foot installed, depending on factors such as roof size, membrane system, and insulation thickness. The TPO membrane itself typically costs between $1.00 to $2.50 per square foot. EPDM roofing, on average, costs between $4.25 and $15 per square foot to install. While higher-quality EPDM materials may come at a premium, they often offer better performance and longevity, potentially offsetting the initial cost difference between the two roofing systems.
3. Installation Method
Both TPO and EPDM roofing systems offer various installation methods, each with its own advantages. TPO membranes can be installed using mechanical fasteners, bonding adhesives, or ballasting systems. Fully adhered TPO roofs provide excellent protection against air bubbles and shifting but take longer to install. Mechanically attached TPO membranes offer quicker installation but may be prone to moisture pockets between fasteners.
EPDM roofing can also be installed using fully adhered, mechanically attached, or ballasted methods. The fully adhered method, which involves bonding the EPDM membrane directly to the roof surface using adhesive, is the most common installation technique for EPDM roofing systems. Ballasted EPDM roofs use materials like gravel or pavers to secure the membrane, while mechanically fastened EPDM roofs are secured to the roof substrate using mechanical fasteners.
4. Energy Efficiency
When it comes to energy efficiency, TPO roofing holds an advantage over EPDM roofing due to its reflective properties. TPO roof membranes help reduce heat absorption and cooling costs during warm weather, making them an energy-efficient choice for buildings in hot climates. While EPDM roofing is not inherently reflective, proper insulation and ventilation practices can still contribute to energy savings in buildings with EPDM roof systems.
5. VOC-Free Installation
Both TPO and EPDM roofing systems offer environmentally friendly installation options. TPO roofing can be adhered without the use of additional VOC-containing adhesives, making it a green choice for eco-conscious building owners. EPDM roof materials can also be manufactured sustainably, with both low-VOC and no-VOC options available. The long lifespan of EPDM roofing membranes keeps these products out of landfills for extended periods, and worn-out EPDM roofs can be recycled.
6. Maintenance Requirements
Maintenance is an important factor to consider when comparing TPO roofing versus EPDM roofing. TPO roofs require a regular maintenance schedule to extend their lifespan, including routine washing and debris removal. In contrast, EPDM roofing systems are known for their low maintenance requirements, often withstanding years of neglect without developing leaks or issues. This difference in maintenance needs can impact the long-term cost and effort associated with each roofing system.
7. Puncture Resistance
TPO roofing membranes generally offer superior puncture resistance compared to EPDM roofing. TPO roof systems provide approximately three times more protection against punctures than EPDM membranes. This makes TPO roofing a more suitable choice for areas prone to debris impact or heavy foot traffic. EPDM roofing, while durable, has weaker seams and lower puncture resistance, which may make it less ideal for high-impact areas.
8. Chemical Resistance
When it comes to chemical resistance, TPO roofing outperforms EPDM roofing in most cases. TPO membranes are more resistant to chemicals, mold, and physical damage than EPDM roofing systems. This makes TPO roofing a better choice for industrial environments where chemical spills may occur. However, it’s worth noting that TPO membranes can be vulnerable to damage from contact with greases or oils. EPDM roofing membranes have lower resistance to certain solvents, oils, and chemical abrasives, which may limit their suitability in some industrial settings.
9. Fire Resistance
Both TPO and EPDM roofing systems offer good fire resistance properties, but there are some differences to consider. TPO roofing is generally rated as a Class A fire-resistant material, providing excellent protection against fire hazards. EPDM roofing also possesses inherent fire-retardant qualities that enhance its safety profile. Flame-retardant EPDM significantly decreases heat and smoke release, making it a suitable choice for areas prone to fire hazards. The fire resistance of both roofing systems contributes to the overall safety of buildings.
10. UV Rays And Heat Resistance
TPO roofing generally has excellent UV resistance due to its reflective properties. The typically white or light-colored surface of TPO membranes enhances their ability to reflect sunlight, helping to reduce heat buildup in buildings. This can lead to lower cooling costs and improved energy efficiency. TPO roofing also demonstrates good heat resistance and can handle high temperatures effectively.
EPDM roofing also offers good UV resistance, but its performance in this area can vary depending on the color of the membrane. Traditional black EPDM roofing tends to absorb more heat, which may not be ideal for hot climates. However, EPDM roofing can still perform well under UV exposure, especially with proper maintenance and protective coatings. EPDM membranes exhibit good heat resistance and can withstand high temperatures without degrading, making them durable in various climate conditions.
11. Cold Resistance
Both TPO and EPDM roofing systems perform well in cold weather conditions. TPO roof membranes can expand and contract without cracking, making them suitable for varying weather conditions. TPO roofing can withstand impacts from temperatures as low as -50°F. EPDM roofing membranes also remain flexible and pliable in extremely cold temperatures, with a brittleness temperature of -49°F (-45°C) according to ASTM standard D 746. This cold resistance makes both TPO and EPDM roofing systems viable options for buildings in regions with harsh winter climates.
12. Wind Resistance
When it comes to wind resistance, TPO roofing has a slight edge over EPDM roofing. TPO roof systems can resist winds from Category 3 hurricanes, which have speeds between 110 mph to 130 mph. EPDM roofing, while still wind-resistant, is more prone to damage when wind speeds exceed 100 mph. This difference in wind resistance may be a crucial factor for buildings in areas prone to high winds or severe storms.
13. Hail Resistance
Both TPO and EPDM roofing systems offer good hail resistance, but their performance varies. TPO roofing membranes can resist damage from hailstones up to 1.75 inches in diameter. EPDM roofing, particularly adhered systems with a minimum 60-mil non-reinforced membrane, has been shown to resist up to 3-inch simulated hail impact without fracture or damage to the membrane. Ballasted EPDM roofs perform especially well during hailstorms, as the rock ballast serves to break the ice balls upon impact and protects the underlying membrane from damage.
14. Material’s Strength
When comparing the material strength of TPO roofing versus EPDM roofing, both systems have their strengths. TPO roofing has a tear strength of 55 lbf, while EPDM roofing slightly outperforms it with a tear strength of 60 lbf. However, TPO roofing demonstrates superior break strength at 427 lbf, compared to EPDM roofing’s minimum break strength of 200 lbf. In terms of tensile strength, EPDM roofing reaches 3,625 lbf, while TPO roofing shows higher compressive strength at 7,977 lbf compared to EPDM’s 3,600 lbf. These strength characteristics impact the overall durability and performance of each roofing system in different environmental conditions.
TPO Or EPDM? Which Roofing System Is Better?
In conclusion, the choice between TPO roofing and EPDM roofing depends on various factors, including climate, budget, energy efficiency goals, and specific building requirements.
TPO roofing offers advantages in energy efficiency, puncture resistance, and chemical resistance, making it suitable for many commercial applications.
EPDM roofing excels in longevity, low maintenance, and cold weather performance, making it a reliable choice for long-term roofing solutions.
Both roofing systems have their strengths and can provide excellent protection for flat or low-slope roofs when properly installed and maintained. Ultimately, the best choice between TPO and EPDM roofing will depend on the specific needs of your building and local environmental conditions.
