A modified bitumen roof is a flexible asphalt-based flat roof system built to withstand heat, UV exposure, and storm damage. Property owners researching modified bitumen roof systems or comparing built-up roof vs modified bitumen often choose this option for its balance of cost, performance, and ease of maintenance.
There are two main types of modified bitumen membranes used in both commercial and residential modified bitumen roof systems:
are rubber-modified and flexible, making them ideal for buildings in areas like Phoenix and Glendale that experience wide temperature swings.
are more rigid and UV-resistant—perfect for the constant sun exposure in Buckeye and surrounding areas.
Whether you’re installing a 3-ply modified bitumen roof or a simpler 1- or 2-layer system, choosing the right material ensures durability and weather protection.
A complete modified bitumen roof system typically includes multiple layers installed over flat or low-slope roofs. These systems can be torch-applied, cold-applied, or self-adhered, depending on building type and safety requirements.
You’ll often see these systems called flat roof modified bitumen or detailed in architectural plans as modified bitumen roof detail. In dry, high-heat climates like Arizona, proper modified bitumen roof installation ensures long-term performance and energy efficiency.
Built for year-round exposure in places like Phoenix
Protects against monsoon damage in Glendale, Buckeye, and beyond
Modified bitumen roof repair is often fast and affordable
Can be paired with reflective coatings or insulation
Works well for both commercial and residential applications
With basic modified bitumen roof maintenance, most systems last 15 to 30 years, even in Arizona’s harsh climate. Lifespan depends on installation quality, slope, drainage, and sun exposure.
Adding a modified bitumen roof coating every 7–10 years can further extend its life and reduce surface temperature. This helps lower cooling costs in high-heat cities like Phoenix.
Common questions include:
Both versions reflect the same answer: up to three decades with proper care.
The modified bitumen roof cost per square foot typically ranges from $5 to $12, depending on:
You can also choose from various modified bitumen roof colors, which may impact both aesthetics and energy efficiency.
Built-up roofs (BUR) use hot asphalt and multiple layers of felt. They’re durable but labor-intensive. A modified bitumen roof uses factory-made membranes for faster installs and better elasticity—ideal for Arizona’s temperature shifts.
TPO and EPDM are popular single-ply membranes. TPO reflects heat better, while EPDM is flexible and rubber-based. However, modified bitumen roof membranes are thicker, multi-layered, and often more puncture-resistant—especially valuable during monsoon season or foot traffic on rooftops.
Modified bitumen roofs are widely used across Phoenix, Glendale, and Buckeye on commercial buildings, schools, multifamily housing, and residential homes with low-slope roofs. If your existing system is nearing the end of its life or struggling with storm damage, roof replacement with modified bitumen offers a durable, cost-effective option.
It’s also an excellent upgrade from older rolled roofing or foam systems, offering better waterproofing and more modern energy efficiency.
Capstone Roofing has over 40 years of experience installing and repairing flat roof systems in Arizona. We provide free estimates for modified bitumen roof repair, installation, or full replacement. Whether you’re managing a commercial property in Glendale or upgrading a residential flat roof in Buckeye, our team is here to help.
Learn more about:
Q: What is a modified bitumen roof?
A: It’s a flat roofing system made from asphalt reinforced with rubber or plastic polymers. It’s designed for flexibility, water resistance, and long-term durability—perfect for Arizona weather.
Q: How long does a modified bitumen roof last?
A: Most systems last 15 to 30 years with proper installation and upkeep.
Q: How much does a modified bitumen roof cost per square foot?
A: The cost ranges from $5 to $12, depending on material, number of plies, and labor method.
Q: What’s the difference between modified bitumen and a built-up roof?
A: BUR uses layers of felt and asphalt applied hot. Modified bitumen comes in rolled sheets, installs faster, and adapts better to movement and heat.
Q: Is this a good option for Arizona homes?
A: Yes. It’s a top choice for flat roofs in Phoenix, Glendale, and Buckeye due to heat resistance and monsoon protection.