Modified Bitumen Roofing
Modified bitumen is one of the most popular flat roofing systems in San Francisco, valued for its durability, flexibility, and proven waterproofing performance. Standard Roofing Company installs and repairs mod-bit systems across the city.
Book OnlineAbout Modified Bitumen
Modified bitumen roofing consists of asphalt-based sheets reinforced with fiberglass or polyester, and modified with rubber or plastic polymers for enhanced performance. It's applied in overlapping layers to create a seamless, waterproof barrier.
There are two main types: SBS (styrene-butadiene-styrene), which adds rubber-like flexibility, and APP (atactic polypropylene), which adds plastic-like durability. Both perform well in San Francisco's climate.
Advantages
- ✓ Excellent waterproofing for flat and low-slope roofs
- ✓ Good flexibility in cool, foggy conditions
- ✓ Multi-layer application adds redundancy
- ✓ 15–20+ year lifespan with proper maintenance
- ✓ Relatively straightforward to repair
Need Modified Bitumen Work?
Whether you need a new mod-bit roof, repairs, or just want to know how your existing one is holding up, request a free estimate.