Metal Roofing Products

Interlock® Aluminum Metal Roofing: Five Architectural Profiles, One Lifetime Engineering Platform

Slate, Cedar Shingle, Shake, Mediterranean Tile, and Standing Seam — built on a single 3105-H24 aluminum platform with the Alunar® coating system and the Interlock® Lifetime Transferable Warranty.

Interlock® Aluminum Metal Roofing reproduces the appearance of slate, cedar shingle, shake, Mediterranean tile, and standing seam in a single engineered platform — built to last the lifetime of your home with no painting, sealing, or re-roofing.

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Aluminum Metal Roofing | 5 Profiles · UL 2218 Class 4 · Lifetime Warranty | Interlock®

Overview

What Is Interlock® Aluminum Metal Roofing?

Interlock® Aluminum Metal Roofing is a complete architectural roofing platform built on a single material foundation — 3105-H24 aluminum alloy (ASTM B209) at 0.019" nominal thickness, finished with the Alunar® 5-layer fluoropolymer coating system, and backed by the Interlock® Lifetime Transferable Warranty. Across five profile families — Metal Slate, Metal Cedar Shingle, Metal Shake, Mediterranean Metal Tile, and Standing Seam — every Interlock® aluminum panel carries the same metallurgical, structural, and warranty specification. Choose the profile that fits your architecture; the engineering underneath is identical.

At approximately 40–70 lbs per square (depending on profile), Interlock aluminum installs on standard roof framing without structural reinforcement — eliminating the load-bearing requirements of natural slate (800–1,500 lbs/sq), concrete tile (500–1,000 lbs/sq), and even three-tab asphalt (250–350 lbs/sq). The four-way interlocking panel system creates a unified, watertight surface with no exposed fasteners, warranted to 120 mph wind resistance, rated Class 4 under UL 2218 for hail impact, and available with Class A fire classification per ICC-ES ESR-1790 when installed with the specified underlayment. Color-matched aluminum trim completes every transition — no field-fabricated flashing required.

One installation eliminates the two-to-three replacement cycles asphalt roofs require over a 50-year ownership window — a documented $15,000–$25,000 recurring cost. The aluminum substrate is 100% recyclable at end of service life, contributes to LEED Materials & Resources credits, and qualifies for insurance premium reductions in markets where Class 4 impact ratings trigger discounts. For homeowners, architects, and contractors making a permanent roofing decision, Interlock® Aluminum Metal Roofing is the engineering-grade alternative to every disposable roofing category on the market — across five profile choices, one lifetime engineering platform.

Who It's For

Interlock® Aluminum Metal Roofing for Every Audience

You want a roof that looks beautiful, lasts decades, and never needs painting, re-granulating, or emergency repairs. Interlock® Aluminum Metal Roofing delivers all three across five architectural profiles — choose the look (slate, cedar shingle, shake, Mediterranean tile, or standing seam) and inherit the same lifetime engineering. The Alunar® coating system holds color for 30+ years, the Lifetime Transferable Warranty adds documentable resale value, and the Class 4 hail rating can reduce homeowner insurance premiums in qualifying markets. One installation, lifetime performance — in the profile that fits your home.

Interlock® Aluminum Metal Roofing is specified under CSI MasterFormat Section 07 31 16 (Metal Shingles — Slate, Cedar Shingle, Shake, Mediterranean Tile profiles) and Section 07 41 13 (Metal Roof Panels — Standing Seam profile). The 0.019-inch aluminum alloy 3105-H24 panel (ASTM B209) installs at approximately 40–70 lbs per square depending on profile, eliminating the structural reinforcement requirements common with slate, clay, and concrete alternatives. The Alunar® 5-layer fluorocarbon coating system delivers PVDF-based color retention rated to ASTM D-4214-07 (chalk resistance) and ASTM D-2244-16 (color retention). Cool Roof performance is confirmed by CRRC and ORNL testing. ICC-ES Evaluation Report ESR-1790, Florida Product Approval FL7263-R7 (NON-HVHZ), and CCMC 10475-R validate performance in applicable jurisdictions. Minimum slope: 3:12 with ice-and-water underlayment; 5:12 with standard underlayment. Class A fire rating available per ESR-1790 §4.4 when installed with GAF Versashield per ESR-2053. UL 2218 Class 4 hail impact. Wind warranted to 120 mph under the Guardian Lifetime Limited Non-Prorated Warranty. 30-year coating warranty. One-time transferable. Master spec sheet, panel profile drawings, and CSI-formatted submittal language available on request.

Interlock's four-way interlocking installation system is engineered for efficient, repeatable installation by trained professionals across all five aluminum profiles. Each panel clicks into adjacent panels horizontally and vertically, creating a watertight system without exposed fasteners. Certified Interlock installers receive training, technical support, and access to the Interlock dealer network spanning North America. Individual panel replacement is possible without disturbing surrounding panels, simplifying warranty service across every profile. Contact your regional Interlock representative to discuss dealer opportunities.

KEY ADVANTAGES

The Interlock® Aluminum Advantage

Lifetime Transferable Warranty

Every Interlock® Aluminum installation — Slate, Cedar Shingle, Shake, Mediterranean Tile, or Standing Seam — is backed by the same Lifetime Transferable Warranty. The strongest warranty in the residential roofing industry. Coverage can be transferred one time to the next owner (a $300 transfer fee applies), protecting your home’s resale value.

Class 4 Impact Resistance

Interlock® Aluminum achieves the highest UL 2218 impact rating — Class 4 — verified by the standard’s 2-inch steel-ball impact test under standardized drop conditions. Many insurance providers offer premium discounts for Class 4 rated roofing systems, applied uniformly across every Interlock® aluminum profile.

Class A Fire Resistance available

Class A fire rating available under ASTM E108 — the highest fire resistance classification — when installed with the specified underlayment assembly. Interlock® Aluminum provides superior fire protection compared to asphalt shingles, untreated wood shake, and many traditional roofing categories.

120 MPH Wind Resistance

Interlock’s concealed clip-fastening system locks every panel to the roof deck and to the panels around it, with no exposed fasteners that can loosen or back out over time. The system is warranted against wind uplift to 120 mph and tested to ASTM D3161 Class F, while the interlocking design lets panels expand and contract with temperature swings without breaking the weather seal — so the roof is built to stay secure through the high winds and seasonal storms common across North American climates.

Energy-Efficient Design

Interlock® aluminum panels reflect solar energy and release absorbed heat rapidly after sunset, reducing attic temperatures and HVAC cooling loads compared to dark asphalt shingles. Cool Roof rated by both CRRC and ORNL, every Interlock® aluminum profile delivers measurable energy savings year-round.

Low Lifetime Maintenance

No painting, re-granulating, sealing, or re-nailing — ever. Interlock® Aluminum Metal Roofing requires only occasional rinsing to remove debris, across all five profiles. Eliminate the recurring cost and disruption of asphalt shingle maintenance from your budget permanently.

AAMA 2605 Certified Coating System

The Alunar® Coating System — Built for Lifetime Color

Every Interlock® Aluminum panel — across all five profiles (Slate, Cedar Shingle, Shake, Mediterranean Tile, and Standing Seam) — is factory-finished with the proprietary Alunar® Coating System: a 5-stage molecular bonding process engineered to the most demanding performance standards for architectural coatings in North America. At its core, Alunar uses a 70% polyvinylidene fluoride (PVDF) fluoropolymer resin system — the same chemistry trusted by monumental and commercial building projects across the continent. Unlike painted steel or granule-coated asphalt products, PVDF fluoropolymer chemistry does not fade, chalk, peel, or blister. Color stability is independently verified to ASTM D-4214-07 (chalk resistance) and ASTM D-2244-16 (color retention) — requiring less than 5 Delta E units of color change after a decade of continuous UV exposure. Your roof’s color is not applied to the surface — it is bonded into it. That is the difference between a finish that lasts 20 years and one that lasts a lifetime.

Layer 1 — Alunar® Coating System (PVDF Top Coat)

The outermost layer is Interlock’s proprietary Alunar fluoropolymer finish — formulated with 70% polyvinylidene fluoride (PVDF) resin and independently verified to ASTM D-4214-07 for chalk resistance and ASTM D-2244-16 for color retention. This layer delivers color stability confirmed to less than 5 Delta E color change after ten years of continuous UV exposure. It is the permanent face of your roof.

Layer 2 — Primer Base Coat

A precision-applied primer layer bonds directly to the treated aluminum surface, creating the adhesion foundation that locks every subsequent layer in place. This primer is the structural bridge between the metal substrate and the PVDF color system — without it, no coating chemistry performs to specification.

Layer 3 — Conversion Coating

A chemical conversion treatment restructures the aluminum surface at the molecular level — transforming it from a passive metal into an active bonding substrate. This layer is critical to corrosion resistance and long-term coating adhesion, and is what separates an architectural-grade finish from a standard painted surface.

Layer 4 — Alkaline Cleansed

Before any coating is applied, each aluminum panel undergoes a multi-stage alkaline cleaning process that removes surface oxides, mill oils, and microscopic contaminants. This step is non-negotiable — surface cleanliness at this stage directly determines the lifespan of every layer above it.

Layer 5 — Aluminum Substrate

The structural foundation of every Interlock® Aluminum panel — 3105-H24 aluminum alloy, selected for its superior formability, corrosion resistance, and long-term dimensional stability. At approximately 40–70 lbs per square depending on profile, it is seven to thirty times lighter than natural slate (800–1,500 lbs/sq) and requires no structural reinforcement on standard roof framing across any of the five available profiles.

Layer 6 — Back Coat

An applied protective coating on the underside of every panel guards against moisture infiltration, condensation, and galvanic corrosion from below. Most roofing products leave the back face uncoated. Interlock does not — because a lifetime warranty requires protection on all six sides of the panel.

Technical Data

Product Specifications

Specification	Details
Base Material & Alloy Specification	Aluminum alloy 3105-H24 per ASTM B209
Panel Gauge & Nominal Base Thickness	0.019" (0.483 mm) nominal base thickness
Installed Weight Per Square	Approx. 40–70 lbs per 100 sq ft (varies by profile: Slate ~41, Cedar Shingle ~45, Standing Seam 40–50, Shake ~58, Mediterranean Tile ~70)
Hail Impact Resistance Rating	Class 4 — UL 2218
Fire Resistance Rating	Class A fire rating available (requires GAF Versashield Fire-Resistant Roof Deck Protection per ICC-ES ESR-2053; self-adhered underlayment = non-classified assembly)
Wind Speed Resistance — Manufacturer Warranted	120 mph (193 kph) — warranted per manufacturer's installation procedures
Surface Coating System & Finish Warranty	Alunar® Coating System — 5-layer fluorocarbon finish; 30-year coating warranty (no chalk >8 ASTM D-4214-07; no color change >5 ΔE ASTM D-2244-16)
Panel Size, Weather Exposure & Coverage Geometry	Varies by profile — see individual product pages for panel dimensions and weather exposure (Slate 17⅝" × 9"; Cedar Shingle, Shake, Mediterranean Tile, and Standing Seam each have their own geometry)
Material Warranty Program Name	Guardian Lifetime Limited Material Warranty — one-time transferable
Warranty Duration, Ownership Terms & Transferability	Lifetime for original registered owner (individual); 50 years from Substantial Completion for organizations or upon transfer to 2nd owner ($300 transfer fee)
Recycled Content & End-of-Life Recyclability	Aluminum is 100% recyclable at end of life
Cool Roof Energy Rating & Third-Party Certification	Cool Roof rated — CRRC (Cool Roof Rating Council) and ORNL (Oak Ridge National Laboratories) tested
CSI MasterFormat Division & Section Reference	07 31 16 — Metal Shingles (Slate, Cedar Shingle, Shake, Mediterranean Tile profiles); 07 41 13 — Metal Roof Panels (Standing Seam profile)

Available Colors

The Interlock® Aluminum Color Palette

The Interlock® Aluminum color palette is offered in eight architect-curated colors applied through the Alunar® PVDF fluoropolymer coating system. Each color is engineered to meet ASTM D-4214-07 chalk resistance (numerical rating no worse than 8) and ASTM D-2244-16 color retention (color change no greater than 5 Hunter ΔE units). Unlike paint-over-steel or granule-coated products that fade, chalk, or shed over time, Alunar’s 70% PVDF resin chemistry is backed by a 30-year color warranty — guaranteeing these thresholds are measured, testable, and warranted performance commitments, not marketing language. The same eight-color palette applies uniformly across all five Interlock® Aluminum profiles — Slate, Cedar Shingle, Shake, Mediterranean Tile, and Standing Seam — so you can specify any color in any profile. For projects requiring solid copper rather than PVDF-coated aluminum, see the separate Interlock® Copper Roofing line — a distinct material category in 99.9% pure Copper Alloy C11000 (ASTM B370) with a naturally evolving patina finish. Contact your local Interlock dealer to request physical color samples in the profile and finish of your choice.

Material Comparison

Interlock® Aluminum vs. Asphalt vs. Stone-Coated Steel

How does Interlock® Aluminum Metal Roofing compare to the dominant residential roofing alternatives? The numbers tell a clear story about lifetime value, performance, and total cost of ownership — applied uniformly across every Interlock® aluminum profile.

Specification	Interlock® Aluminum Metal Roofing	Asphalt Shingles	Stone-Coated Steel
Lifespan	Lifetime (50+ years)	15-25 years	40-50 years
Weight	40-70 lbs/square (varies by profile)	250-350 lbs/square	140-180 lbs/square
Fire Rating	Class A available	Class A (with mat)	Class A
Warranty	Lifetime Transferable	20-30 year limited	30-50 year limited
Maintenance	Low maintenance	Periodic inspection, re-nailing	Periodic inspection (granule loss)

Environmental Performance

Sustainability & Energy Efficiency

Interlock Metal Slate is manufactured from aluminum — one of the most sustainable structural building materials available. Aluminum is 100% recyclable at end of life with no degradation in material quality, and Interlock panels contain a high percentage of post-industrial recycled content. Its permanent service life eliminates the repeated manufacturing, transport, and landfill cycles embedded in conventional roofing replacement. Cool Roof certification from CRRC and ORNL confirms measurable energy performance contributions. For homeowners, architects, and sustainability-focused developers, Interlock Metal Slate delivers documented lifecycle environmental performance.

Interlock Metal Slate may contribute to LEED v4 credits under Materials & Resources (MR) — Recycled Content, and Energy & Atmosphere — Enhanced Energy Performance. Contact your Interlock dealer for LEED documentation support.

Verified Customer Reviews

What Homeowners Say About Interlock Metal Roofing

This is the 3rd roof I have had put on by Interlock Roofing. I put one on my original house, my cottage, and now my new house. They have always done an excellent job, and the aluminum shingles are a great product — light, sturdy, and good-looking, even years down the road.

Bruce M.Wakefield, MA

We had our roof replaced in 2017 with an aluminum roof by Interlock Metal Roofing. We live on the lake, and prior to the replacement, we were spending thousands of dollars every year as the shingles used to fly away in the wind. We have never had any problems in the last 9 years. We had a great experience with Interlock Metal Roofing. They were very professional and did a beautiful job, although it was difficult as our roof is quite high. Our roof is still beautiful, and we have never had a worry about it.

Beena M.Sudbury, ON

I LOVE MY INTERLOCK ROOF! No more climbing up there to clean it off, no more gritty stuff falling into my garden after a few years. It looks fabulous and does what it's supposed to! And then there are the installers: knowledgeable, attentive to detail, and personable. Ivan is a gem! He attended to the addition of a small bit of flashing efficiently and cleaned the whole roof with a blower in short order. After almost ten years, it's STILL the only roof I would choose!

Sue Lyn T.Corvallis, OR

FAQ

Frequently Asked Questions About Aluminum Metal Roofing

What is Interlock® Aluminum Metal Roofing?

Interlock® Aluminum Metal Roofing is a residential roofing platform built on 3105-H24 aluminum alloy (ASTM B209) at 0.019″ nominal thickness, finished with the proprietary Alunar® 5-layer PVDF fluoropolymer coating system. The platform is offered in five architectural profiles — Metal Slate, Metal Cedar Shingle, Metal Shake, Mediterranean Metal Tile, and Standing Seam — all sharing the same material substrate, four-way interlocking installation system, eight-color Alunar® palette, and Lifetime Transferable Warranty. The variable is the visual profile; the underlying engineering is identical across all five.

Does aluminum roofing dent in hail?

Interlock® Aluminum Metal Roofing is rated UL 2218 Class 4 for hail impact — the highest classification issued under the standard, equivalent to withstanding a 2-inch steel ball dropped from 20 feet with no through-penetration or fracture. Functional performance is preserved; minor cosmetic dimpling can occur in exceptional hail events but does not affect the water-shedding envelope or the warranty. Asphalt shingles, by comparison, typically fail at UL 2218 Class 1 or Class 2 under the same test. Many insurance providers offer 5–35% premium discounts for Class 4 rated roofs in qualifying jurisdictions.

Will aluminum roofing make my home noisier when it rains?

No. Interlock® Aluminum Metal Roofing is installed over solid roof decking and standard underlayment, not over open purlins like the agricultural barn roofs that produce the “rain on a tin roof” sound people associate with metal. Independent acoustic testing of decked metal roofing assemblies consistently measures rain noise within 1–3 decibels of asphalt shingle assemblies — a difference below the threshold of perceptible loudness to most occupants. With standard attic insulation, the interior is acoustically indistinguishable from a conventional shingle roof.

How does aluminum roofing compare to galvanized or Galvalume steel roofing?

Aluminum and steel are both common metal roofing materials with distinct corrosion and weight profiles. Aluminum (Interlock uses 3105-H24 alloy) is naturally corrosion-resistant — it forms a self-passivating oxide layer that prevents rust formation, making it particularly suited to coastal salt-air environments where galvanized and Galvalume steel can fail at cut edges and fastener penetrations. Aluminum weighs approximately 40–70 lbs per square versus 100–150 lbs/sq for steel, reducing structural load. Steel can offer higher tensile strength for long spans, but for residential roofing aluminum is the preferred substrate for lifetime corrosion performance, lower structural demand, and the documented multi-decade service life behind the Interlock® Lifetime Transferable Warranty.

How long does Interlock® aluminum roofing last?

Interlock® Aluminum Metal Roofing is warranted for the lifetime of the original registered homeowner under the Guardian Lifetime Limited Non-Prorated Material Warranty. Documented installations from the 1970s remain in continuous service today with original color retention and structural integrity. The Alunar® PVDF coating system is independently warranted to ASTM D-4214-07 (chalk resistance no worse than rating 8) and ASTM D-2244-16 (color change less than 5 Hunter ΔE units) for a minimum of 30 years. The aluminum substrate itself has no defined end of service life — it is 100% recyclable rather than degradable.

Is aluminum roofing too heavy for my existing roof framing?

The opposite — Interlock® aluminum is among the lightest residential roofing materials available. At approximately 40–70 lbs per square (varies by profile), it is 5–8 times lighter than asphalt shingles (250–350 lbs/sq), 7–15 times lighter than concrete or clay tile (500–1,500 lbs/sq), and 20–30 times lighter than natural slate (800–1,500 lbs/sq). Standard residential roof framing is engineered well in excess of Interlock’s installed load. In most cases, Interlock® aluminum can be installed without any structural reinforcement, and is one of the few roofing categories that can be specified for retrofit installations over existing decks where heavier materials would require framing upgrades.

What's the difference between the five Interlock® aluminum profiles?

All five Interlock® aluminum profiles — Metal Slate, Metal Cedar Shingle, Metal Shake, Mediterranean Metal Tile, and Standing Seam — share the same 3105-H24 aluminum substrate, Alunar® coating system, eight-color palette, four-way interlocking installation system, Lifetime Transferable Warranty, and Class 4/Class A/120 mph performance specifications. What varies is the visual profile: Slate reproduces the appearance of quarried natural slate; Cedar Shingle the texture of split cedar shingles; Shake the hand-split appearance of heavy cedar shake; Mediterranean Tile the rolled S-profile of clay barrel tile; and Standing Seam the vertical-rib profile common in architectural commercial roofing. Select the profile that fits your architecture — the engineering underneath is identical.

Can Interlock® aluminum roofing be installed over existing shingles?

In many cases, yes. Interlock® Aluminum is light enough (40–70 lbs/sq) to be installed over a single layer of existing asphalt shingles, subject to local building code approval, roof deck condition assessment, and proper underlayment installation. This approach can reduce installation cost and labor time, and eliminates the landfill disposal of the existing asphalt layer. Heavier roofing categories (slate, tile, concrete) typically require full tear-off to avoid exceeding structural load capacity — a limitation that does not generally apply to Interlock® aluminum. Your local Interlock dealer will perform a deck and structure assessment as part of the project specification.

Will Interlock® aluminum roofing reduce my home insurance premium?

In many jurisdictions, yes. Interlock® Aluminum Metal Roofing carries a UL 2218 Class 4 impact rating — the highest classification issued under the standard. Insurers in hail-prone states (Texas, Oklahoma, Kansas, Colorado, the Carolinas, and others) offer premium discounts ranging from 5% to 35% for Class 4 rated roofs, often categorized as “impact-resistant” or “Class 4 hail” discounts. The Class A fire rating (when installed per ICC-ES ESR-1790 with the specified underlayment assembly) can also qualify for wildfire-zone insurance discounts in California, Arizona, Colorado, and other Western jurisdictions. Contact your insurance provider with the Interlock® specifications and the Guardian Lifetime Warranty documentation to confirm applicable credits.

Is aluminum roofing more expensive than asphalt shingles in the long run?

No — over a typical home ownership window, Interlock® Aluminum is the lower-cost option. Asphalt shingles last 15–25 years and require 2–3 full re-roofing cycles over a 50-year ownership window at $15,000–$25,000 per cycle. Interlock® Aluminum is installed once and warranted for the lifetime of the home. When the recurring asphalt replacement cycles, removal labor, landfill disposal fees, and energy savings from Cool Roof performance are factored in, the total cost of ownership for Interlock® Aluminum is consistently lower across published comparisons by the NRCA, Remodeling Magazine’s Cost vs. Value report, and the Metal Construction Association.

Profiles

Explore Other Interlock Roofing Profiles

Last modified: May 22, 2026 12:37 pm