Roofing Systems
Modified Bitumen.
Multi-layer redundancy.
The modern evolution of the old built-up roof. Multiple layers of asphalt-based membrane installed in plies. If one layer gets punctured, the next layer is still keeping you dry. That redundancy is the whole point.
Best For
Schools, government buildings, institutional facilities, buildings with high foot traffic or rooftop equipment service, and recovers over existing built-up roof systems.
Service Life
20-30 years.
Twenty to thirty years for properly installed multi-layer systems with reflective cap sheets and proper maintenance. Single-ply mod-bit installations or systems with the wrong material for the climate fall well short of this. Multi-layer systems with the right specification routinely reach the upper end.
How It Works
Multiple plies, with redundancy built in.
Modified bitumen is the modern evolution of the old built-up roof. Multiple layers of asphalt-based membrane installed in plies, with each layer adding another barrier between weather and the building. If one layer gets punctured, the next layer is still keeping you dry. That redundancy is the whole point.
There are two flavors: SBS (rubber-modified, flexes well in cold) and APP (plastic-modified, holds up better in hot UV-heavy climates). For Texas and the Gulf Coast, APP is usually the right call.
Operational Profile
The system to consider when rooftop equipment service is constant.
Moderate maintenance, moderate install disruption (especially torch-applied systems), high foot-traffic tolerance, moderate energy performance with reflective cap sheet. Puncture and impact resistance is materially better than any single-ply system. This is the system to consider when rooftop equipment service is constant.
What You Should Know
Climate drives the SBS-vs-APP call.
The choice between SBS and APP is climate-driven. Wrong material for the climate is the single most common cause of early failure we see on these roofs.
Where It Falls Short
Open-flame work and weight.
Installation involves open-flame torch work on some systems, which presents real fire risk and requires authorized applicators. Buildings with combustible materials underneath may need different installation methods. Modified bitumen is also heavier than single-ply. Your building’s structure has to handle the added weight, especially on a recover.
Get Started
Right system for your building? Let’s confirm.
The right roofing system is decided by data, not preference. We start every engagement with a documented Roof Health Assessment so the recommendation is the right one for your building, your operation, and your hold horizon.