Metal Roofing in Saint John, New Brunswick

Yes — aluminum's non-porous oxide layer expands and contracts without cracking or absorbing water. Saint John experiences about 87 freeze-thaw days per year, a proven stress test for roofing materials. Unlike asphalt shingles that embrittle or wood that splits, roofing-grade 3105-H24 aluminum alloy (ASTM B209) moves freely without degradation. The four-way interlocking panels shed water instantly, so no moisture gets trapped during temperature swings. The 30-year coating warranty (ASTM D4214/D2244) covers the entire freeze-thaw service life — no degradation, no callbacks.

Metal roofs shed snow more effectively than asphalt because their smooth, slippery surface prevents accumulation. Saint John receives about 150 cm of snow annually, and ice dams form when heat melts snow unevenly. Interlock's four-way interlocking system creates a unified surface that promotes drainage and prevents water pooling. The panels are also extraordinarily light — the Slate profile weighs just 0.41 lb/sq ft — so no structural reinforcement is needed. This means your home supports the same roof weight whether empty or bearing the winter snow load, and installation is faster.

Interlock panels are warranted to resist wind speeds up to 120 mph (193 km/h), and Saint John's typical wind gusts reach about 128 km/h. The four-way interlocking design locks each panel on all four edges, distributing lateral force across the entire roof system rather than relying on fasteners alone. This overlap and locking mechanism is tested under IBC/IRC standards (ICC-ES ESR-1790, reissued 2025). When installed to specification by a certified contractor like Maritime Metal Roofing Ltd., the system resists both sustained wind and powerful gusts without panel lift or separation.

Metal roofing sheds heavy rainfall instantly because water runs off the smooth, hard surface — it cannot permeate aluminum. Saint John receives about 1215 mm of rain yearly, and the four-way interlocking panel design creates overlapped seams that channel water down and out. Unlike asphalt shingles, which absorb water and degrade around nail holes, aluminum has no fastener penetrations along panel edges. The solid deck and proper underlayment installed by Maritime Metal Roofing ensure water directed to the perimeter drains safely to gutters and downspouts, with no leak risk even during heavy coastal rainfall.

Aluminum cannot rust because it contains no iron — rust requires iron oxide to form. When aluminum is scratched or exposed, it instantly forms a thin, transparent oxide layer that heals automatically and protects the base metal underneath. Interlock panels are coated with Alunar 70% PVDF fluorocarbon on both sides, adding a 30-year warranty against fading and chalking (ASTM D4214/D2244). In Saint John's coastal-influenced salt-air environment, this dual-layer protection (self-healing oxide plus protective coating) is the reason Interlock roofs installed since 1998 in similar climates show zero rust or corrosion, even after decades of exposure.

Interlock metal roofing achieves UL 2218 Class 4 impact rating — the highest available — and the warranty covers perforation from hailstones up to 1.5 inches. Class 4 means the roof resists impact that would dent or crack asphalt shingles or tile. Many insurers offer premium discounts for Class 4-rated roofs because repair costs are near zero even after severe hail. Saint John's 2777 annual sunshine hours mean hail is less frequent here than in prairie regions, but when spring storms occur, a Class 4-rated roof protects both your home and your wallet. Contact your insurer — they may adjust your rate once the roof is installed and certified by Maritime Metal Roofing Ltd.

Interlock backs every roof with The Guardian — a lifetime limited, non-prorated material warranty for the original owner covering rusting, rotting, splitting, cracking, curling, and loss of impact resistance. This warranty is one-time transferable: the next owner receives 50 years of coverage from completion. Unlike asphalt shingles (15–20 years) or standard metal roofs (20–30 years prorated), you'll never file a claim for material failure. Combined with the 30-year coating warranty on the Alunar finish, your investment is protected across the decades. This is the last roof you'll buy for your home.

Installation timelines vary with roof size and complexity, but most homes are completed within 3–5 days. One major advantage: Interlock's light weight (Slate at 0.41 lb/sq ft, Shake at 0.58, Tile at 0.59) allows installation directly over existing asphalt shingles in most cases — no tear-off and landfill cost. The panels install with proper underlayment and fastening to a solid deck, meeting ICC-ES ESR-1790 code requirements. Maritime Metal Roofing Ltd. has served the Saint John region since 2007 and will assess your roof structure during a free inspection, confirming whether an overlay is safe or if removal is needed. Currently, enjoy interest-free payments for 3 months — a smart way to fit premium roofing into your budget.

Virtually none beyond annual gutter cleaning — metal roofing is CALGreen-verified for reduced maintenance. Unlike asphalt shingles (which require periodic sealing and show granule loss), wood shakes (which split and rot), or tile (which cracks and requires resealing), Interlock aluminum panels are inert. They do not absorb water, do not degrade from UV exposure (the Alunar coating is warranted 30 years against fading), and resist the freeze-thaw stress that degrades other materials. Saint John's 87 annual freeze-thaw days, 1215 mm rain, and 150 cm snow all accelerate wear on traditional roofing — but not on aluminum. Your roof simply sheds water and weather, year after year.

Metal roofing costs more initially than asphalt but far less over the roof's life. Asphalt lasts 15–20 years, requiring replacement twice in 40 years; metal lasts indefinitely under The Guardian lifetime warranty. Factor in tear-off and disposal costs, labor inflation, and the disruption of two more roof projects — metal's total cost of ownership is lower. Saint John's severe climate — 150 cm snow, 1215 mm rain, 87 freeze-thaw days, and gusts to 128 km/h — accelerates asphalt failure but does not affect aluminum. Current promotion: save at least $2499 on installation and pay with interest-free monthly payments for 3 months. This is the last roof you buy, and the numbers prove it.