Quick answer
What kind of gutters work best on a metal roof in Charleston? Gutters set high enough and far enough out to catch fast water, sized at 6 inch or larger, with enough downspouts to drain them. Rain leaves a metal roof faster than it leaves shingles, so a gutter that works on a shingle roof can get overshot in a Lowcountry downpour. Match the metal to your setting, too: aluminum near salt water, Galvalume inland under a matching roof, and copper only where its runoff never touches another metal. For a free written estimate call (843) 867-2267 or get a free quote.
Fast water
Why metal roofs are hard on gutters
Metal roofs are everywhere in the Lowcountry, from standing seam on downtown single houses to new builds out by the marsh. They shed rain beautifully, and that is the problem.
Shingles slow water down. Every row is a little speed bump. A smooth metal panel does not, so in a heavy rain the water reaches the roof edge moving fast and in a solid sheet.
A gutter hung too low or tucked too far back gets jumped. The water flies over the front lip and lands at the foundation, on the steps or under a raised house.
And Lowcountry rain is the kind that does this. NOAA Atlas 14, which we checked for Mount Pleasant on the federal rainfall frequency server, puts the hardest single hour of rain in an ordinary year at 1.74 inches. In short bursts it comes down far harder, about 6.11 inches an hour over five minutes.
Sources: NOAA Atlas 14 (Volume 2), Mount Pleasant point estimate, retrieved October 2026; National Hurricane Center season dates.
The fit
Putting the gutter where the water actually lands
On a metal roof, where the gutter sits matters as much as how big it is.
The goal is simple: the roof edge should empty into the middle of the trough, not over the back edge or past the front. On a metal roof that can mean setting the gutter a little higher or farther out than it would sit under shingles, while keeping a steady slope to each outlet.
Size and downspouts
We hang 6 inch gutters on most Lowcountry homes, and a metal roof is where that extra room pays off. Very large roofs, long low slopes and condo buildings can call for 7 inch gutters with oversized downspouts. Either way, a gutter only drains as fast as its outlets, so long runs and corners where two roof planes meet often get an extra downspout.
Lower roofs
Watch where the upper roof empties. A downspout that dumps onto a porch roof or a lower metal section sends a concentrated stream down that panel, straight at a short gutter below. That lower gutter needs to be sized for both roofs, or the upper downspout carried down past it.
The metal
Matching the gutter metal to the roof
A metal roof and a metal gutter have to get along, and in salt air the wrong pairing shows up fast.
| Your roof and setting | Gutter that usually fits | Watch out for |
|---|---|---|
| Galvalume or bare metal roof, inland | Galvalume gutters in the same gun metal tone | Salt exposure if you are near the water |
| Any metal roof on the islands or by the marsh | Aluminum, which has no iron in it to rust | Hardware that is not compatible with aluminum |
| Painted metal roof in a color | Colored aluminum matched to the roof or trim | Checking the sample in afternoon sun |
| Copper roof or copper accents | Copper gutters with copper downspouts and hangers | Copper runoff landing on any other metal |
Galvalume gutters look right under a matching roof, but it is still steel under a coating. The marine guidance from one major steel maker keeps Galvalume back at least 1,500 feet from breaking surf and 400 feet from salt marsh, which is why we mostly recommend it inland, in places like Summerville. On Isle of Palms or Folly Beach, aluminum is the safer call, in colored aluminum if you want it to match.
Copper looks wonderful and outlasts everything, but water running off it makes aluminum or galvanized steel underneath corrode faster. A copper roof gets copper gutters and copper downspouts, start to finish.
The upkeep
Keeping a metal roof gutter working
A metal roof lasts a long time. The gutter under it should keep up.
- Watch the first big storm.Stand where you can see the roof edge. Water sailing past the front of the gutter means it needs to move out or up.
- Clean on the Lowcountry calendar.Once when the spring live oak drop is over, and a second time after the autumn straw comes down.
- Check after every named storm.Look for hangers pulled loose, seams dripping and downspouts knocked off their straps.
- Follow every downspout down.Each one should empty well away from the foundation, the stairs and the space under a raised house.
- No water shooting over the front of the gutter in a downpour.
- No copper runoff landing on aluminum or steel.
- No rust streaks or white powder on gutters, hangers or screws.
- Downspouts carry water clear of the house.
Under live oaks and pines, BroGuard gutter guards sit inside the gutter and keep leaves and straw out, so a fast roof never meets a clogged trough. Our coastal and raised home gutters page goes deeper on salt air, and our hurricane season gutter prep covers the storm side. Our owner, Gabe Gomez, is a Marine Corps veteran, and his crews work out of Mount Pleasant. Start with gutter installation.
Gutters overshot by your metal roof? Call (843) 867-2267
Get a Free QuoteLocal tip: look for a clean, bare stripe in the mulch or sand a foot or two out from the wall under a metal roof. That line is where water has been jumping the gutter, and it tells you exactly which run needs attention.
Frequently Asked Questions
Often the water is not overflowing, it is overshooting. Rain leaves a smooth metal roof fast and can fly past a gutter hung too low or set too far back. Repositioning the gutter or going up a size usually fixes it.
Most Lowcountry homes get 6 inch gutters, and that size suits most metal roofs. Very large roofs, long low slopes and condo buildings can need 7 inch gutters with oversized downspouts.
We usually steer coastal homes to aluminum. A major steel maker’s marine guidance keeps Galvalume well back from surf and salt marsh, so it makes the most sense inland, under a matching roof.
Only if the copper runoff never lands on the other metal. Water running off copper makes aluminum and galvanized steel corrode faster, so a copper system should stay copper from top to bottom.
Yes. BroGuard sits inside the gutter and stops live oak leaves and pine needles at the top, so fast water from the roof always meets an open trough.
Free estimates
Is your metal roof outrunning your gutters?
Book a free written estimate with our local crew. We will look at where the water leaves your roof, how the gutters are set and which metal suits your spot in the Lowcountry.
The Brothers That Just Do Gutters · Charleston · (843) 867-2267 · Veteran owned and operated in Mount Pleasant, serving the Lowcountry