Gutters for a metal roof aren’t just an aesthetic detail. Indeed, they protect your walls, your foundation and the area around your home against water damage. In other words, choosing the wrong gutters is like installing a 50-year roof with a weak link that will fail after 10.
In this article, we compare the gutter materials available and explain which ones are compatible with a metal roof. We also detail the mistakes to avoid so that your entire system lasts as long as your roof.
The role of gutters on a metal roof
Water running off a metal roof behaves differently from water leaving a shingle roof. Indeed, the smooth surface of metal speeds up runoff. Water therefore reaches the gutters with more force and volume. As a result, your gutters must be sized for this flow.
In winter, snow also slides off a metal roof more easily. Snow guards control this release, but some of the melting snow still reaches the gutters. If they aren’t sturdy enough, the weight of the ice can then bend them or tear them off.
In addition, gutters for a metal roof must withstand the same weather conditions as the roof itself. In concrete terms, in Quebec, that means extreme temperatures and repeated freeze-thaw cycles. Fragile or poorly fastened gutters simply won’t survive these conditions.
Which material should you choose?
The material of your gutters must be compatible with your metal roof, both chemically and in terms of durability. Here are the main options available.
- Steel: it’s the most consistent choice with a steel roof. Indeed, steel gutters last as long as the roof covering, that is, 50 years or more. In fact, Metal Roof Canada offers steel gutters with a 50-year warranty that match its roofs.
- Aluminum: lightweight, corrosion-resistant and available in several colours. It’s the most popular material in Quebec. However, it bends more easily under the weight of ice.
- Copper: very durable, with a lifespan of more than 100 years. Its high cost, however, limits it to high-end projects.
- Vinyl (PVC): the cheapest, but also the least durable. Indeed, it becomes brittle in the cold and yellows in the sun. With a 50-year roof, it’s therefore a poor choice.
As a general rule, choose a material whose lifespan is close to that of your roof. A system that ages at the same pace thus saves you costly interventions.
Watch out for compatibility between metals
Not all metals get along. Indeed, when two incompatible metals are in direct contact, a reaction called galvanic corrosion occurs. One of the two then corrodes much faster than it would on its own. In fact, this is a common trap when choosing gutters for a metal roof.
For example, copper gutters under a galvanized steel roof speed up the deterioration of the steel. Indeed, water running over the copper carries ions that attack the protective zinc. As a result, within a few years, corrosion appears at the edge of the roof.
Steel-on-steel or aluminum-on-aluminum combinations, on the other hand, pose no problem. However, avoid copper with steel and copper with aluminum. A specialized roofer knows these incompatibilities and chooses the right materials from the start.
Sectional or seamless gutters?
The type of gutter directly influences its durability. There are two options: sectional gutters and seamless gutters.
Sectional gutters are assembled from 10- to 12-foot sections joined together. However, each joint represents a potential weak point. Indeed, over time, the caulking between sections can crack and let water through.
Seamless gutters, for their part, are custom-made directly on site. A portable machine forms the metal into a single piece along the entire length of the wall. The result: no joints and therefore no potential leaks. They thus fit the shape of your home perfectly.
For a metal roof designed to last for decades, seamless gutters are therefore the logical choice. They also require less maintenance over the years. The initial investment is admittedly slightly higher, but the peace of mind is well worth it.
Mistakes to avoid
Some mistakes come up frequently when installing gutters for a metal roof. By knowing them, you can avoid them from the start.
- Undersizing the gutters: a metal roof sheds water faster than shingles. Gutters that are too small therefore overflow during heavy rain.
- Neglecting the slope: without enough slope toward the downspouts, water pools and freezes in winter. The metal then bends under the pressure.
- Using incompatible metals: as explained above, copper and steel don’t mix. So always check compatibility.
- Forgetting snow guards: on a metal roof, indeed, snow avalanches can tear gutters off in one go. Properly placed snow guards prevent this risk.
- Fastening the gutters to the siding: instead, gutters must be firmly anchored to the fascia or the roof frame to support the weight of ice.
In short, by avoiding these mistakes, you considerably extend the life of your gutters and protect your entire system.
Gutter maintenance
Even the best gutters require minimal maintenance. In general, two cleanings a year are enough, in spring and fall. If trees overhang your roof, however, add a cleaning in the summer.
During cleaning, first remove the leaves, branches and debris that have built up. Then check that the slope is still correct and that the fasteners are holding firmly. Indeed, sagging gutters create points where water accumulates. This excess water can then work its way up under the panels and cause leaks.
Also, inspect the downspouts. A blockage prevents water from draining and therefore causes overflow along the wall. In winter, this overflow freezes and damages the exterior siding. Keeping downspouts clear also helps prevent ice dams.
Finally, gutter guards are an interesting option. These screens keep debris out of the gutters and thus considerably reduce how often you need to clean them.
Conclusion
Gutters for a metal roof must live up to the roof they accompany. Choose a compatible, durable material, favour seamless gutters and avoid incompatible metal combinations. A well-designed system protects your walls and foundation for as long as your roof.
Don’t let unsuitable gutters compromise a roof designed to last 50 years. It’s a modest investment that perfectly complements your roof.
Planning a new roof or a gutter replacement? Contact Metal Roof Canada for a complete system, from ridge to downspouts.
