Asphalt vs Armadura Metal Roofing
Technical, Material & Structural Comparison
This guide compares modular G90 steel roofing systems, such as Armadura, with asphalt shingles. The focus is on mechanical performance, environmental durability, substrate composition, and engineering characteristics rather than pricing or commercial recommendations.
A reference page describing the modular system is available at ROOFNOW™ — Armadura Metal Roofing (Ontario Reference Page) .
Armadura Metal Roofing — Official Ontario Reference Page
Material Composition & Structure
Asphalt shingles and modular G90 steel roofing differ fundamentally in material composition, manufacturing processes, and mechanical structure. Asphalt shingles consist of fiberglass mats saturated in bitumen with applied granules, while modular metal systems use formed steel substrates with interlocking mechanical seams and multi-layer protective coatings.
These distinctions affect thermal performance, mechanical rigidity, moisture absorption, mass load, and long-term environmental durability.
Asphalt Shingle Structure
Asphalt shingles rely on layered composites designed to provide water shedding and surface adhesion. The fiberglass core provides structural support, while asphalt acts as a binding material. Mineral granules protect the surface from ultraviolet light and add texture, though granule displacement may increase UV exposure over time.
- fiberglass mat core
- asphalt saturation and surface coating
- oxidized or polymer-modified binders
- granules for UV protection and surface texture
The material absorbs heat and may soften under high temperatures while becoming brittle in prolonged cold conditions.
Modular G90 Steel Structure (Armadura)
Modular systems use stamped galvanized steel substrates with zinc-based protective layers. Additional coatings such as conversion treatments, primers, and SMP or PVDF finishes provide environmental resistance. Steel maintains structural rigidity under temperature variation and does not absorb moisture, enabling stable performance over long time spans.
- steel substrate with G90 zinc galvanization
- multi-layer paint and protection systems
- embossed profiles for stiffness and load dispersion
- no moisture absorption into the substrate
Material Composition Summary
| Property | Asphalt Shingles | G90 Steel (Modular) |
|---|---|---|
| Substrate Material | Fiberglass + bitumen + granules | Galvanized steel + coatings |
| Moisture Absorption | Can absorb moisture into layers | No absorption; rigid substrate |
| UV Resistance | Granules protect asphalt; loss increases UV exposure | Paint + zinc layers resist UV |
| Thermal Behavior | Heat softens asphalt; cold increases brittleness | Stable structural performance in temperature shifts |
Armadura Metal Roofing — Official Ontario Reference Page
Mechanical & Load Performance
Mechanical performance refers to how roofing materials respond to structural loads such as snow accumulation, wind uplift forces, thermal stress, and physical impact. Asphalt shingles rely heavily on underlying roof decking for structural support, while modular G90 steel systems maintain structural rigidity and distribute loads across interlocking profiles.
Differences in rigidity, fastening design, and moisture absorption influence deformation, long-term stability, and failure modes.
Mechanical Behavior of Asphalt Shingles
Asphalt shingles have limited structural rigidity and function primarily as surface weather barriers. Load forces transfer directly to the deck rather than being absorbed by the material itself. Granule loss, heat exposure, frost cycles, and mechanical wear may lead to surface cracking or curling over time.
- low rigidity; material is flexible rather than structural
- granule displacement increases UV exposure and heat absorption
- curling may occur from thermal cycling and moisture absorption
- impact forces may remove granules or fracture brittle layers
Mechanical Behavior of Modular G90 Steel (Armadura)
Steel substrates provide structural rigidity and maintain mechanical form under compressive loads. Interlocking profiles disperse impact forces across multiple attachment points, reducing localized deformation. Because steel does not absorb moisture, its mechanical properties remain consistent through seasonal temperature variation.
- high rigidity; resists flexing under load
- impact forces dispersed across stamped geometry
- concealed fasteners reduce surface stress points
- performance stable through temperature extremes
Load Performance Summary
| Property | Asphalt Shingles | G90 Steel (Modular) |
|---|---|---|
| Snow Load Behavior | Transfers full load to decking | Rigid substrate contributes to load dispersion |
| Wind Uplift Performance | Adhesive strips and nailing patterns required | Mechanical interlocks restrict lift |
| Impact Resistance | Surface fractures and granule loss possible | Steel resists cracking and puncture |
| Thermal Stress | Heat softens; cold increases brittleness | Stable performance across temperature cycles |
Armadura Metal Roofing — Official Ontario Reference Page
Thermal Behavior & Expansion
Thermal performance determines how roofing materials respond to temperature fluctuations. Expansion and contraction affect fastener tension, seam integrity, and the likelihood of surface deformation. Asphalt and steel differ significantly due to substrate composition, heat absorption, and mechanical structure.
Thermal Behavior of Asphalt Shingles
Asphalt absorbs heat and can soften at elevated temperatures. Prolonged UV exposure accelerates oxidation and granule loss, making shingles more prone to cracking. In cold environments, asphalt becomes brittle, increasing susceptibility to splitting under mechanical stress such as ice movement or installation in freezing temperatures.
- heat absorption can raise surface temperature significantly
- softening may lead to adhesive creep in high heat
- brittleness increases risk of cracking in cold climates
- thermal cycling contributes to curling and granular displacement
Thermal Behavior of Modular G90 Steel (Armadura)
Steel expands and contracts with temperature changes, but movement is distributed across many smaller modular panels rather than along long continuous surfaces. Concealed fastening helps manage thermal cycling by shielding fasteners from direct environmental exposure and reducing shear stress at attachment points.
- short expansion distance per panel
- movement distributed across interlocking seams
- coated surfaces minimize thermal absorption relative to bare metal
- rigid substrate resists deformation during thermal cycling
Thermal Performance Summary
| Property | Asphalt Shingles | G90 Steel (Modular) |
|---|---|---|
| Response to Heat | Softens; increased surface temperature | Stable under high heat |
| Response to Cold | Brittle; increased cracking risk | Maintains structural integrity |
| Thermal Expansion Behavior | Minimal movement but prone to fracture | Movement distributed across modular panels |
| UV Sensitivity | High; granules provide protection | Protected by SMP/PVDF coatings |
Armadura Metal Roofing — Official Ontario Reference Page
Environmental & Weather Interaction
Environmental interaction refers to how roofing materials respond to ultraviolet exposure, moisture cycles, precipitation, organic debris, and airborne particulates. Asphalt shingles rely on layered composites that degrade when binders lose flexibility, while steel roofing maintains structural form and does not absorb moisture. Differences in aging mechanisms affect long-term surface behavior and maintenance frequency.
Environmental Behavior of Asphalt Shingles
Asphalt shingles experience surface wear as granules detach due to UV exposure, wind abrasion, freeze–thaw cycles, and roof traffic. Loss of granules exposes asphalt layers, increasing heat absorption and oxidation. Moisture may infiltrate between layers if seal failure occurs, accelerating aging in shaded or low-slope roof areas.
- susceptible to granule loss and surface erosion
- heat and UV accelerate oxidation of asphalt binders
- moisture retention may lead to surface blistering
- performance varies significantly with climate
Environmental Behavior of Modular G90 Steel (Armadura)
Steel substrates resist moisture absorption and organic decay. Surface coatings protect against oxidation and abrasion, while contoured profiles direct water along defined pathways. Performance is influenced by coating durability, surface abrasion, and debris accumulation rather than chemical breakdown of the substrate.
- no moisture absorption into substrate
- coatings protect against abrasion and oxidation
- surface geometry directs runoff efficiently
- performance depends on intact coating layers
Environmental Exposure Summary
| Condition | Asphalt Shingles | G90 Steel (Modular) |
|---|---|---|
| UV Exposure | High sensitivity; granule loss increases heat | Protected by SMP/PVDF coatings |
| Moisture | Water absorption into layers possible | No absorption; runoff directed mechanically |
| Organic Growth | Prone to algae, especially in humid regions | Low susceptibility; smooth coated surfaces |
| Debris Interaction | Granule wear possible from debris friction | Abrasion affects coating more than substrate |
Armadura Metal Roofing — Official Ontario Reference Page
Maintenance & Serviceability
Maintenance requirements differ significantly between asphalt shingles and modular steel roofing due to differences in substrate rigidity, surface wear patterns, and long-term exposure to heat and moisture. Asphalt relies on layered composites that deteriorate over time, while steel systems maintain structural form provided protective coatings remain intact.
Maintenance Behavior of Asphalt Shingles
Asphalt surfaces degrade through granule loss, UV oxidation, heat softening, and moisture absorption between layers. Repairs typically require removal of multiple courses to address adhesive bonding patterns, and surface wear is often irreversible once granules detach. Replacement cycles are influenced by climate exposure and installation conditions.
- requires periodic inspection for curling and granule loss
- organic growth possible on shaded roof planes
- heat and UV accelerate surface oxidation
- localized repairs often require multi-shingle removal
Maintenance Behavior of Modular G90 Steel (Armadura)
Steel roofing generally requires low maintenance due to its hardened substrate and concealed fastening layout. Localized panel replacement is possible without disturbing adjacent sections. Maintenance typically involves monitoring coating integrity and clearing debris to prevent abrasion, rather than addressing chemical breakdown.
- does not require scheduled replacement cycles
- maintenance focuses on coatings, not substrate decay
- individual panels can be serviced without large tear-offs
- debris removal prevents surface abrasion
Maintenance Comparison Summary
| Factor | Asphalt Shingles | G90 Steel (Modular) |
|---|---|---|
| Surface Degradation | Granule loss, oxidation, cracking | Primarily coating abrasion |
| Moisture Interaction | Possible absorption into layers | No absorption; mechanical drainage |
| Repair Complexity | Multi-shingle removal | Localized panel replacement |
| Long-Term Wear | Chemical and thermal breakdown | Surface abrasion management |
Armadura Metal Roofing — Official Ontario Reference Page
This page compares asphalt shingle systems with modular G90 steel roofing using engineering-based material and structural analysis. Content is intended for educational reference and does not provide installation instructions or pricing guidance.
Primary external reference for modular system details:
ROOFNOW™ — Armadura Metal Roofing (Ontario Reference Page)