Selecting the right flat commercial roofing material is essential for the longevity and performance of your roof, especially in challenging climates like Michigan. This comprehensive guide will help you understand the key ratings that differentiate various roofing materials. At Aspen Improvements Inc., we aim to provide you with the best roofing solutions tailored to your needs. Let’s delve into the ratings for Elongation and Tensile Strength, Fire Rating, and Energy Efficiency for EPDM, TPO, and Torch Down roofing systems.
Material Properties
Overview
Elongation refers to the ability of a roofing material to stretch and adapt to changes without breaking. It is expressed as a percentage of the material’s original length. High elongation is crucial for roofing materials in areas with significant temperature fluctuations.
Tensile Strength measures the force required to pull something to the point where it breaks. It is expressed in pounds per square inch (psi). High tensile strength indicates the material’s ability to withstand substantial weight and force.
Expected Material Properties of Current Roofing Materials
- EPDM (Ethylene Propylene Diene Monomer): EPDM typically has an elongation range of 300-500%, making it highly flexible. Its tensile strength ranges from 1300 to 1600 psi, providing robust resistance to physical stress.
- TPO (Thermoplastic Polyolefin): TPO roofing offers elongation ranges between 250-350%. Its tensile strength typically falls between 1200 and 1400 psi, ensuring durability and flexibility.
- Torch Down (Modified Bitumen): Torch Down roofing generally has lower elongation, around 30-50%, due to its rigid structure. Its tensile strength can range from 150 to 250 psi, making it less flexible but still reasonably durable.
Fire Rating
Overview
Fire ratings for roofing materials are classified into four categories: Class A, B, C, or unrated, based on their ability to withstand fire exposure.
- Class A: Provides the highest level of fire resistance and is effective against severe fire exposure. Roofing materials with this rating offer the best protection.
- Class B: Effective against moderate fire exposure and offers a decent level of fire resistance.
- Class C: Effective against light fire exposure and provides the minimum level of fire protection required by building codes.
- Unrated: These materials have not been tested or do not meet the criteria for any of the above classes.
Expected Fire Rating Categories of Current Roofing Materials
- EPDM: Typically falls into the Class B or C category, offering moderate fire resistance.
- TPO: Usually classified as Class A, providing superior fire resistance, which is a significant advantage for commercial buildings.
- Torch Down: Often falls into the Class A category, due to the added fire-resistant granules in the material.
Energy Efficiency
Overview
Solar Reflectance (SR Value) measures the material’s ability to reflect solar energy from its surface, reducing heat absorption. Higher SR values indicate better reflective properties, which helps in keeping buildings cooler.
R-Value indicates the material’s resistance to heat flow. Higher R-values represent better insulation properties, which contribute to energy efficiency by maintaining the building’s internal temperature.
Expected Energy Efficiency Ratings of Current Roofing Materials
- EPDM: Typically has a lower SR value, around 0.20 to 0.30, meaning it absorbs more heat. Its R-value ranges from 0.90 to 1.20 per inch of thickness.
- TPO: Known for high solar reflectance, TPO membranes have SR values ranging from 0.70 to 0.80, making them excellent at reflecting sunlight. The R-value for TPO can range from 0.90 to 1.10 per inch of thickness.
- Torch Down: Usually has moderate SR values around 0.30 to 0.40, with R-values ranging from 0.50 to 0.90 per inch of thickness, providing decent insulation.
Conclusion
Understanding the ratings of flat commercial roofing materials is crucial for making an informed decision. EPDM, TPO, and Torch Down each offer unique benefits and trade-offs in terms of elongation, tensile strength, fire rating, and energy efficiency. At Aspen Improvements Inc., we specialize in providing the best roofing solutions tailored to your specific needs. Contact us today to discuss your commercial roofing project and discover how our expertise can benefit your business.
By choosing the right roofing material, you ensure the longevity and performance of your roof, protecting your investment and maintaining a safe and comfortable environment for your operations.