What Are the Interlock Roof Profiles, and Which Suits Your NC Home?

Interlock Roofing makes six roof options, and four of them are aluminum shingle profiles:

• Slate: the most popular profile, with the flat, crisp lines of natural slate.
• Cedar Shingle: the look of sawn cedar shingles, with even courses.
• Shake: the heavier, more textured look of split cedar shakes.
• Mediterranean Tile: the curved, rolling look of clay barrel tile.
• Standing Seam: long aluminum panels joined by raised vertical seams.
• Solid Copper: a copper roof, chosen for its color and the way it weathers.

The four shingle profiles are pressed from heavy-gauge aluminum and finished with the Alunar 70% PVDF coating, built to the AAMA 2605 standard. Each panel shows several slates, shingles or tiles on its face. On the roof, the panels lock to each other on all four sides and the fasteners are concealed under the course above. About 98% of Interlock roofs sold are aluminum.

Interlock roofs are manufactured by Interlock Roofing in Delta, British Columbia, and are Made in North America. In North Carolina they are sold and installed by authorized dealers such as Metal Roof NC.

The Slate profile suits most North Carolina houses, which is a big part of why it is the most popular. It gives a roof the flat, shadow-lined look of natural slate without slate's weight. Natural slate needs heavy framing; Interlock aluminum panels weigh roughly 0.4 to 0.7 lb per square foot.

Slate fits brick Colonial Revival and Georgian-style homes in older Raleigh, Durham and Greensboro neighborhoods, where slate was the traditional roof on many of the grander houses. It also fits the two-story brick-and-siding homes common in Cary, Apex, Wake Forest and the Charlotte suburbs, where a darker slate roof reads as a step up from asphalt without looking out of place next door.

Popular slate colors include Deep Charcoal, Black and Musket Grey, which work with red brick, painted brick and white or gray siding. In July 2023, Metal Roof NC completed two neighboring Durham homes in Deep Charcoal with the slate profile. For more on the product itself, see aluminum shingles.

The difference is texture and shadow. Cedar Shingle copies sawn cedar shingles: smoother faces, even thickness and clean, regular courses. Shake copies hand-split cedar shakes: a rougher surface, deeper shadow lines and a more rustic look.

Cedar Shingle suits Cape Cod-style homes, cottages, Craftsman bungalows and shingle-style houses where a tidy, traditional look fits. Shake suits farmhouses, mountain and lake houses, timber-frame homes and coastal houses where a heavier, more natural texture fits the setting. Around Jordan Lake, Falls Lake and Lake Norman, and on wooded lots across the Piedmont, browns such as Colonial Brown, Tudor Brown and Sierra Tan are common choices for both.

Why not real cedar? In North Carolina's humid climate, wood roofs need regular care to stay sound, and they collect moss and debris under trees. Aluminum in a cedar profile keeps the look without the wood. If you are replacing a real cedar roof, the cedar is always removed first; see roof replacement and our guide to metal over existing shingles.

Mediterranean Tile makes sense on Spanish Revival, Mission and Mediterranean-style homes, and on some modern and coastal houses where a curved tile roof fits the design. It has the rolling profile of clay barrel tile, which gives strong shadow lines and a warm look, especially in Tile Red.

These houses are less common in North Carolina than in Florida or the Southwest, but you will find them along the coast, in golf and resort communities and scattered through Charlotte and the Triangle. Tile Red is the classic color; browns and Sierra Tan give a softer look that sits well next to stucco and stone. Real clay and concrete tile are heavy and can crack under falling limbs or foot traffic. An aluminum tile profile gives a similar look at a fraction of the weight, which matters if the house was not framed for tile.

If you are replacing existing concrete or clay tile, it must be removed before an Interlock roof goes on. That tear-off is a bigger job than removing asphalt, so ask for it to be priced separately in the estimate.

Standing Seam and Solid Copper are different products from the aluminum shingles, with their own look and specifications. Standing Seam uses long aluminum panels that run from eave to ridge, joined by raised seams. It suits modern farmhouses, contemporary homes, porch roofs and accent areas. Our guide to standing seam vs metal shingles compares the two systems in detail.

One technical point matters for permits and insurers: ICC-ES evaluation report ESR-1790 covers the Interlock shingle, slate, shake and tile profiles. It does not cover Standing Seam, so ask for the Standing Seam documentation separately if your permit office or insurer requests it.

Solid Copper is the premium option. Copper starts bright, turns brown and, over years, develops a green patina, and it is often used on bay windows, porches, dormers and entry roofs as an accent rather than across a whole house. On historic homes in Raleigh, Durham, New Bern and Wilmington, a copper porch or bay roof is a traditional detail that commissions and neighbors tend to recognize. Copper must not drain onto aluminum or galvanized parts. See copper roofing in NC.

Choose the color with the house, the neighborhood and the summer sun in mind, and get any approvals before signing. Interlock colors include Black, Deep Charcoal, Musket Grey, Hunter Green, Colonial Brown, Tudor Brown, Tile Red, Sierra Tan and Copper Penny, plus Solid Copper. Interlock colors carry Cool Roof Rating Council ratings; lighter colors reflect more of the sun's heat, as explained in metal roof colors for NC heat.

Many Triangle and Charlotte subdivisions have HOA architectural committees that approve roof materials and colors. Submit the profile, color and photos of similar roofs and get written approval first; see HOA approval for a metal roof.

In a local historic district, North Carolina law requires a certificate of appropriateness before the exterior of a building is altered, and the statute counts the kind and texture of building materials as exterior features. Raleigh, Durham, Wilmington, Winston-Salem and other cities have historic districts, so check with the local commission before choosing a profile.

The four aluminum shingle profiles perform the same way; you are choosing a look, not a level of protection. That makes the decision simpler than it first seems: settle the style with your eye, your neighbors and your HOA, and let the estimate handle the technical details, which stay the same whichever profile you pick. They share the same aluminum, the same Alunar finish, the same four-sided interlock and concealed fasteners, the same minimum pitch of 3/12 and the same light weight.

Interlock aluminum shingles are rated for winds up to 120 mph when installed to manufacturer specification. Coastal design wind speeds in parts of North Carolina are higher, and the permit office or engineer decides what a specific house must meet; see hurricane-resistant roofing. When installed with two layers of GAF VersaShield® underlayment over a 15/32-inch plywood deck, the Interlock roof assembly can achieve a Class A fire rating (ASTM E108 / UL 790).

The material warranty is the same across the aluminum profiles: the Guardian Lifetime Limited Material Warranty from Interlock Roofing covers material and finish for the original purchaser while they own the home, transferable once, with the second owner covered to 50 years from substantial completion. Details are on our warranties page and on the Interlock roofing page.