Home / Commercial Roofing / Modified Bitumen Roofing
— Commercial Roofing · Modified Bitumen
Layers of protection, built to take a beating.
Modified bitumen is the proven, multi-ply asphalt system for flat and low-slope commercial roofs. Layered redundancy, a tough granular surface, and flexible SBS membranes that flex with Midwest freeze-thaw. Buckshot installs and services it across Wisconsin and Iowa with our own crews.
Free modified bitumen roof quote
WI & IA · We respond in 2 hours
Start with a free roof assessment.
New membrane, a reroof over an aging built-up roof, or a leak you need handled? Tell us about the building and we'll assess it, recommend the right system, and put it in a written proposal. We respond within 2 hours.
— How It's Built
SEC 01 / 07
A roof built in plies, not a single sheet.
Modified bitumen is the modern evolution of built-up roofing. Instead of one membrane, it stacks layers that back each other up, from the deck to the surface.
Base ply
Anchored over insulation to the deck, the first line of waterproofing the rest builds on.
Reinforcement
A fiberglass or polyester mat inside the membrane adds strength and dimensional stability.
Cap sheet
The polymer-modified asphalt membrane, the primary waterproofing layer that takes the weather.
Granular surface
Embedded mineral granules shield against UV and abrasion, and light colors add reflectivity.
— APP vs SBS
SEC 02 / 07
Two modifiers. One is built for our winters.
Modified bitumen comes in two polymer types. The difference matters most in a climate that swings from humid summers to deep freezes.
SBS
Rubber-modified
SBS
APP
Plastic-modified
APP
— Why Modified Bitumen
SEC 03 / 07
Tough, proven, and easy to live with.
Mod-bit has held up commercial roofs for decades. Here's what keeps it on the spec sheet.
Multi-ply redundancy
If one layer is breached, others back it up. Built-in insurance against leaks.
Proven & long-lasting
Decades of real-world track record on commercial roofs, a known quantity, not a gamble.
Tough underfoot
Handles foot traffic and rooftop equipment better than thinner single-ply systems.
Easy to repair
Damage patches cleanly, so spot fixes keep the roof going for years.
— How We Install It
SEC 04 / 07
The right method, applied safely.
Mod-bit can go down several ways, and the best one depends on your building, deck, and what's occupied below. We pick the safest, longest-lasting method and run it with our own crews, never subcontracted.
— Where It Fits
SEC 05 / 07
Made for buildings that take a beating.
Mod-bit is a strong call for flat and low-slope roofs that see foot traffic, rooftop equipment, or just demand a long, dependable life.
Schools & campuses
Long life and easy repair for tight maintenance budgets.
Healthcare
Dependable waterproofing where leaks aren't an option.
Retail & strip centers
Tough, proven roofs over multiple tenant spaces.
Warehouses
Big flat roofs that need durability over square footage.
Government & municipal
A spec-friendly, well-documented, long-life system.
Multi-family
Traffic-tough roofing over apartments and condos.
— Why Buckshot
SEC 06 / 07
Earned, Not Claimed
A torch-down roof is no place to cut corners.
Modified bitumen rewards an experienced crew and punishes a careless one, especially anything involving open flame. Buckshot has been family-owned since 1979, licensed across 24 states, with our own crews and the standards a job like this demands.
— What Homeowners Say
Reviews
— Home Base
Madison, WI · Centerville, IA
— Modified Bitumen FAQ
FAQ
It’s a multi-ply, asphalt-based membrane for flat and low-slope roofs, modified with polymers for flexibility and durability. It’s the modern evolution of traditional built-up roofing.
SBS is rubber-modified and flexible, which suits cold, freeze-thaw climates like Wisconsin and Iowa. APP is plastic-modified for heat and UV and is usually torch-applied. We recommend based on your roof and climate.
Several ways: torch-applied, hot-mopped, cold-applied adhesive, or self-adhering. We choose the safest, best-fit method for your building and follow strict fire-watch practices on torch work.
Mod-bit gives multi-ply redundancy and toughness for traffic and equipment; single-ply is lighter with fewer seams and high reflectivity. We help you weigh both. Compare PVC →
Often, yes. A recover over a sound built-up or existing roof can save on tear-off. We assess the roof and deck first and tell you honestly which approach fits.
A well-installed mod-bit roof commonly runs 15 to 25-plus years with maintenance. Actual lifespan depends on the system, installation, and upkeep. See commercial roofing →
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Free Assessment · Family-Owned Since 1979
Put a tough, layered roof over your building.
Whether it's a new modified bitumen system, a recover over an aging roof, or a leak to chase down, start with a free assessment from a commercial crew licensed across 24 states. We respond within 2 hours.
Buckshot General Contracting, family-owned since 1979. Headquartered at 621 N Sherman Ave, Suite B5, Madison, WI 53704, with a field office in Centerville, IA. Licensed in 24 states. WI Lic. DC-080900045. GAF Master Elite and BBB A+ accredited. Membrane types, application methods, and lifespan ranges are general industry guidance; actual performance depends on the system, building, installation, and maintenance. System type and scope are confirmed on-site and in a written proposal. Credentials and licensing current as of publication.