Modified bitumen, often called mod-bit or torch-down, is asphalt reinforced with polymers and built up in layers. A typical system has a base sheet, one or more ply sheets and a granulated cap sheet on top. Multiple layers mean multiple lines of defense against water.
Why owners choose modified bitumen
- Redundancy. Two or three plies instead of one.
- Durable surface. Holds up well to foot traffic from AC techs and other trades.
- Familiar and repairable. Most roofers can maintain it, and repairs blend in.
- Reflective options. White granulated cap sheets or a reflective coating reduce heat.
Torch-down or self-adhered?
Torch-applied sheets are heated with a torch to bond them. Self-adhered sheets stick without an open flame, which is often the better choice on occupied buildings, near wood framing or where fire watch is a concern. We'll recommend the right method for your building.
GAF RUBEROID® systems
We install GAF's RUBEROID® SBS modified bitumen: base, ply and cap sheets built into a multi-ply system. RUBEROID® EnergyCap™ granule cap sheets add a reflective surface to help keep the roof and the building below cooler. Paired with GAF EnergyGuard™ tapered insulation, the system also fixes ponding.
How we install it
- Tear off to the deck and replace any damaged decking.
- Add tapered insulation or crickets where water ponds.
- Install each ply to an approved system, with lapped and sealed seams.
- Flash walls, curbs, drains and penetrations, and finish with edge metal and coping.
Products we install
See brochures and color charts on our products page.
Modified Bitumen Roofing FAQ
How long does a modified bitumen roof last?
Commonly around 15 to 20 years, and sometimes longer with good drainage, a reflective surface and regular maintenance.
Is modified bitumen better than TPO?
Neither is best for every building. Mod-bit offers multiple layers and handles foot traffic well; TPO is lighter, has fewer seams and is very reflective. We'll explain the trade-offs for your roof.
Do you install mod-bit on homes too?
Yes. Flat sections on homes, like Florida rooms and garages, often use modified bitumen. See our <a href="flat-roofing.html">flat roofing page</a>.
Where we work
Doral · Medley · Hialeah · Miami Gardens · Miami · Miami Beach · Sunny Isles Beach · Aventura · Fort Lauderdale · Pompano Beach · Hollywood · Pembroke Pines · Miramar · Davie · Sunrise · Coral Springs · and every city in Miami-Dade and Broward