For over 50 years, ethylene-propylene-diene-monomer roofing (EPDM) has been widely used by commercial roofing contractors. Roofers appreciate EPDM for its high durability, weather resistance, heat and UV resistance, and flexibility. This article shares the history of EPDM and why it’s so popular in new construction and roof replacements.
Here’s what you need to know about this versatile roofing material.
The popularity of ethylene-propylene-diene-monomer (EPDM) Roofing by the Numbers
- EPDM is known as a long-lasting, low-maintenance roofing material suitable for various climates. Let’s see how it stacks up in the roofing market.
- It is one of the top three most used single-ply membranes in the North American commercial roofing market at 22%, trailing TPO (38%) and PVC (34%).
- EPDM is most popular in areas like the Greater Toronto Area, where harsh winters make long-term durability a top priority.
The Canadian EPDM market reached USD 114.8 million in 2023 and is expected to grow to USD 160.9 million by 2030, at a CAGR of 4.9% from 2024 to 2030 (Grandview Research).
Commercial usage of ethylene-propylene-diene-monomer roofing
The predominant use of ethylene-propylene-diene-monomer roofing is for flat or low-slope roofs. The most common usages are for commercial, industrial, and institutional buildings. Examples include warehouses, shopping malls, and hospitals.
Why? EPDM meets specifications often found in such structures. For example, its resilience allows it to accommodate roof penetrations, such as skylights and vents, without compromising waterproof integrity. Also, EPDM’s flexibility and resilience allow it to be custom fitted around rooftop equipment.
The basics about EPDM:
- Ingredients: The two main ingredients in ethylene-propylene-diene-monomer are derived from oil and natural gas: ethylene and propylene.
- Color and thickness: Ethylene-propylene-monomer roofing offers a range of options to meet project objectives. Roofers can choose black or white EPDM, which is sold in widths of 7.5 feet to fifty feet. It is available in two thicknesses, 45 and 60 mils.
- Installation: When using ethylene-propylene-diene-monomer roofing, the roofer has several installation options. EPDM can be fully adhered, mechanically attached, or ballasted. The seams of the roofing system can be sealed with liquid adhesives or specially formulated tape.
Early history and evolution of Ethylene-Propylene-Diene-Monomer Roofing Material
In the 1950s, natural rubber supplies couldn’t fulfill the world’s high demand. To meet this need, DuPont developed EPDM, a synthetic rubber with highly durable, long-lasting properties. Its usage grew in the 1970s, when the Middle East oil embargo drove up the price of asphalt-based roofs and lowered the quality of available asphalt. By the 1980s, ethylene-propylene-diene-monomer Roofing dominated the single-ply roofing market.
Ethylene-propylene-diene-monomer roofing manufacturers
How did ethylene-propylene-diene-monomer roofing membrane enter the market? Carlisle Syntec Systems was the first roofing company to use DuPont’s technology in the manufacture of EPDM rubber roofing. Subsequently, Firestone Building Products and Johns Manville each developed their own versions of EPDM roofing.
Since its introduction, numerous enhancements have been made to the system components, making today’s ethylene-propylene-diene-monomer roofing systems far more robust and of greater value than ever before.
EPDM ENHANCEMENTS
4 Key enhancements to ethylene-propylene-diene-monomer roofing
Since the introduction of EPDM, manufacturers have developed several important enhancements.The following four major milestones have heightened performance and increased value for building owners.
EPDM Enhancement #1: Improvements to seams
First, we’ll discuss EPDM membrane seams. In the mid-1980s, a water-tolerant, butyl-based splice adhesive was developed for EPDM roofing seams. However, the seaming process involved multiple steps. Further, the seams were inconsistent due to workmanship techniques and installation conditions.
After another 20 years, customized primers and double-sided seam tape emerged. These products dramatically simplified the seaming process and reduced inconsistencies in workmanship.
Next, in 2005, the key developments were EPDM sheets and factory-applied tape to seams. These items reduced workmanship issues and improved the quality of finished splices for more consistent ethylene-propylene-diene-monomer roofing results.
EPDM Enhancement #2: Improvements to angle change securement
Moving on to the next ethylene-propylene-diene-monomer roofing enhancement, we look at securement. Instead of using wood, nailing strips held the EPDM membrane in place at a 90-degree angle at the base of parapet walls. Manufacturers found that extruded rubber and plastic nailing strips were a much better solution. Without nail strips drying out over time, membranes didn’t “bridge” away from the wall.
Additionally, in 1989, Carlisle Syntec Systems introduced the RUSS (Reinforcing Universal Securement Strip) detail to ethylene-propylene-diene-monomer roofing membranes. In this development, a 6” wide reinforced EPDM membrane is held in place by fasteners and 2” metal seam fastening plates. The EPDM field membrane is then spliced onto the RUSS with the same shear-resistant products used for seaming.
EPDM Enhancement #3: Improvements to puncture resistance
Now let’s explore the topic of puncture resistance in propylene-diene-monomer roofing. In the 1980s, manufacturers sought to overcome the minimal puncture resistance of the original 45-mil non-reinforced EPDM membranes. They introduced a reinforced EPDM sheet that contained an internal reinforcing scrim for added toughness and durability. On a 60-mil membrane, adding reinforcing scrim to the sheet increases puncture resistance by approximately 50%.
Today, contractors can opt for a 90-mil ethylene-propylene-diene-monomer. This thickness delivers twice the puncture resistance of the original 45-mil rubber. This product boasts the most weathering material of any single-ply membrane on the market.
Enhancement #4: Improvements to Flashing Details
Building on to the first three enhancements, advances in flashing have significantly enhanced the performance of ethylene-propylene-diene-monomer roofing. From 1962 to the mid-1980s, manufacturers made flashings from uncured neoprene, which was prone to cracking. In the mid-1980s, manufacturers switched to using cured neoprene, which dramatically improved weathering properties and reduced cracking issues.
Today’s pressure-sensitive flashings feature a full 60-mil EPDM weathering layer that is laminated to 30-mil cured adhesive for a 90-mil total thickness. This added thickness contributes to the durability and robustness of EPDM flashings.
The pros and cons of ethylene-propylene-diene-monomer roofing
What are some of the characteristics of ethylene-propylene-diene-monomer roofing that are important when planning a budget for your commercial roof replacement?
Key factors in the popularity of ethylene-propylene-diene-monomer roofing
The bottom line is that today’s EPDM has come a long way since the 1950s. Its key selling points are its cost-effectiveness, light weight, weather resistance, flexibility in cold climates, low maintenance and ability to be recyclability. Its positive performance in cold temperatures makes it especially useful in Toronto and throughout Canada.
The shortcomings of ethylene-propylene-diene-monomer roofing
While EPDM roofing is a popular roofing membrane, it’s not always an appropriate choice. Its shortcomings include vulnerability to punctures, aesthetic limitations, sensitivity to petroleum-based products, and vulnerability to shrinking and stretching.
In addition, high-quality installation is especially critical to roof performance and lifespan. Poor installation makes EPDM membranes vulnerable to ponding and leaks. Seams, which are glued or taped, often degrade over time if not installed or properly maintained.
Can you decide on the right roofing membrane based on the pros and cons described above?
Overall, knowing the pros and cons of EPDM and other roofing membranes is essential for developers and landlords. But of course, it’s more complicated than the brief introduction in this article. When planning for a new roof or roof replacement, learn how to choose a trusted roofing contractor who can guide you in the right direction based on your project objectives.
Is EPDM roofing right for your next project?
In short, there are advantages and disadvantages to all roofing materials. Figuring out the right materials for your roof can be a challenging task. Is EPDM roofing the right choice, or would another type of product be more appropriate?
For three generations, Elite Roofing & Contractors has delivered superior commercial roofing quality in the Greater Toronto Area. We back our services with 24/7 emergency services. When it’s time to address your roofing needs, contact us for the highest quality craftsmanship and customer service. Get the #EliteAdvantage.
