Metal Roof Gutter Specialists, Northeast Florida
Gutters for Metal Roofs in Florida: Why We Install 7-Inch with 4x5 Downspouts
A metal roof sheds water faster than shingle: the panels are smooth, the pitch is usually steeper, and rain leaves the eave at speed instead of soaking in and trickling. In a Jacksonville downpour that water overshoots a 5-inch gutter and overwhelms a 6-inch. Gutter Pro installs 7-inch K-style seamless aluminum with 4x5 downspouts on metal-roof homes across Northeast Florida, and owner Albert Urbank sizes every roof on site before the quote is written.
The short answer: the right gutter for a metal roof in Florida is 7-inch K-style seamless aluminum with 4x5 downspouts. A 7-inch carries about 22 gallons per minute against 16 for a 6-inch and 11 for a 5-inch, and the 4x5 downspout moves the water out of the trough as fast as a steep metal panel delivers it. Standing seam, 5V crimp and stone-coated steel all behave the same way: no granules to slow the water, a smooth surface, and a pitch that turns a 9 inch per hour Jacksonville storm into a sheet of fast water at the eave. Gutter Pro installs 7-inch on metal-roof homes at $14 per linear foot, hung on hidden hangers at 24-inch maximum spacing or the Alu-Rex single-layer continuous hanger, with stainless fasteners near the coast.
Why Metal Roofs Need Bigger Gutters Than Shingle
Two roofs with the same footprint do not send the same water to the gutter. Asphalt shingle is rough, absorbs a little, and slows the sheet of water on its way down. Metal does none of that. The gutter under a metal roof has to catch water that is moving faster, arriving in a tighter burst, and leaving the eave with enough momentum to clear a narrow trough entirely.
Speed: the water overshoots
On a 6/12 or steeper standing-seam roof, runoff leaves the panel edge in an arc. A 5-inch gutter sits almost entirely inside that arc and gets missed; a 6-inch catches most of it; a 7-inch catches it with margin because the front lip sits an inch further out. Overshoot is the most common complaint we hear from metal-roof homeowners whose builder hung 5-inch: the gutters look fine, the ground under them is still trenched.
Volume: the storm arrives all at once
Jacksonville sees about 53 inches of rain a year with peak bursts near 9 inches per hour in August and September. A 2,000 square foot roof at a standard pitch produces about 12 gallons per minute at that rate, and a metal roof delivers it with no lag. A 5-inch K-style carries about 11 gallons per minute, a 6-inch about 16, a 7-inch about 22. The margin on 7-inch is what keeps the trough from topping over in the first five minutes of the storm.
The downspout decides the rest
A 3x4 downspout has 12 square inches of outlet. A 4x5 has 20. On a long metal roof plane feeding one corner, the 3x4 backs up first and the gutter overflows at the outlet end no matter how wide it is. 7-inch gutters with 4x5 downspouts drain at the rate the roof fills them, which is the whole point of the pairing. See our 6 vs 7 vs 8 inch comparison for the full capacity table.
Pitch and roof length multiply both
Many Florida metal roofs are steeper than the shingle roofs they replaced, and the long uninterrupted panels of a standing-seam roof mean fewer valleys slowing the water. A 50-foot run of 7-inch with a 4x5 at each end handles what a 6-inch run would spill.
Gutter Sizes on a Metal Roof at a Glance
| Spec | 5-Inch (builder default) | 6-Inch | 7-Inch (our metal-roof standard) |
|---|---|---|---|
| Capacity | About 11 GPM | About 16 GPM | About 22 GPM, roughly 40 percent more than 6-inch |
| Downspout | 2x3 | 3x4 (12 sq in outlet) | 4x5 (20 sq in outlet) |
| Overshoot on a 6/12 metal roof | Common | At corners and long runs in heavy rain | Caught, with margin |
| Gutter Pro installs it | Never | Shingle roofs, moderate pitch, up to about 3,000 sq ft | Metal and tile roofs, steep pitch, 3,000+ sq ft, long roof planes |
| Guard options | Not installed | LeafBlaster Pro micromesh, Alu-Rex DoublePro | LeafBlaster Pro micromesh in 7-inch sizing, Alu-Rex single-layer continuous hanger |
| Installed price | Not offered | $9 per linear foot | $14 per linear foot, 0.032 seamless aluminum |
Capacity and price figures are the same ones published in our Florida gutter pricing report. 8-inch is the step above 7-inch for estate and commercial metal roofs; see 8-inch gutters in Jacksonville.
How We Install Gutters on a Metal Roof
Metal-roof gutter work is mostly about the details at the eave. Get them right and the system is invisible for decades; get them wrong and water runs behind the gutter into the fascia.
- Fascia-mounted, never through the panel. The gutter hangs on hidden hangers screwed into the fascia at 24-inch maximum spacing, or on the Alu-Rex single-layer continuous hanger. Nothing penetrates the roof panel or the seams.
- Drip edge laps into the trough. The panel's eave trim is set so it directs water into the gutter and the back of the gutter sits behind it. Wind-driven rain on a coastal metal roof finds any gap here, so this is checked on every run.
- Front lip set for the roof's arc. On steep panels the gutter is positioned so the fast-moving sheet lands inside the trough, not on the lip.
- 4x5 downspouts placed by roof plane. Outlets go where the water actually arrives, routed away from the slab or into underground drainage.
- Stainless fasteners near the coast. Salt air works on every screw head. Within a mile of the ocean the fasteners are stainless or marine-grade.
- Metals that get along. Aluminum gutters pair with galvalume and painted-steel panels. Copper gutters are fine under a steel roof because the roof drains onto the copper; what we never do is let copper drain onto aluminum.
- Seamless, formed on site. 0.032 aluminum, one continuous run per roof edge from the roll-forming machine in your driveway, miters sealed at the corners.
Gutter Guards on a Metal Roof
Guards matter more under a metal roof than most people expect, because the same speed that overshoots a small gutter also drives leaves and pine straw into the trough. LeafBlaster Pro 316 stainless micromesh is made in 7-inch sizing and sits on the gutter, never under the panel, so the roof warranty is untouched. On 7-inch the Alu-Rex option is the single-layer continuous hanger; Alu-Rex DoublePro is a 6-inch product. We set the guard angle to the roof pitch so fast water sheets through the mesh instead of skating over it. Our gutter guards guide compares the options.
Metal roof, undersized gutters? We measure it free
Albert Urbank checks pitch, panel type, roof-plane lengths and downspout placement on site, and the written itemized quote is the price the job is installed at.
Get a Free QuoteWhat 7-Inch Gutters Cost on a Metal-Roof Home
7-inch K-style seamless aluminum from Gutter Pro is $14 per linear foot installed, plus $110 per first-story downspout; second-story runs add $1 per foot and $220 per downspout. The ranges below use the same footage assumptions as the house-size table in our pricing report.
| Home size | Typical gutter footage | Downspouts | 7-inch, single-story | 7-inch, two-story |
|---|---|---|---|---|
| 1,800-2,200 sq ft | 150-200 ft | 4-6 | $2,540-$3,460 | $3,130-$4,320 |
| 2,400-2,800 sq ft | 190-240 ft | 6-7 | $3,320-$4,130 | $4,170-$5,140 |
| 3,000-3,500 sq ft | 240-320 ft | 7-8 | $4,100-$5,400 | $5,100-$6,600 |
| 4,000+ sq ft | 320-400 ft | 8-10 | $5,400-$6,700 | $6,600-$8,200 |
Guards add $12 per foot for LeafBlaster Pro micromesh and $14 per foot for the Alu-Rex continuous hanger guard; stainless hardware adds $1 per foot near the coast. Run the free Jacksonville gutter cost calculator for your footprint, or see every rate on the Florida gutter pricing report. New installs carry our lifetime workmanship warranty.
Replacing a Metal Roof? Do the Gutters in the Same Week
Most metal roofs in Northeast Florida go on as replacements for shingle, and the builder-grade 5-inch gutters usually get rehung by the roofer. That is the moment to size up: the fascia is exposed, the drip edge is new, and the 7-inch run goes on clean. Our guide to coordinating gutters with a roof replacement covers the sequence, and a new metal roof plus a properly sized gutter and drainage system is also the combination that insurers ask about at renewal.
Our Metal-Roof Gutter Process
On-Site Assessment with Owner Albert
Albert measures each roof plane, notes pitch and panel type, and looks for the overshoot and washout lines that show where the existing gutters have been losing the fight.
Sizing Plan
Capacity is worked plane by plane: footage, pitch, panel type and the number and placement of 4x5 outlets. The written quote lists it all, and the quote is the install price.
HOA, ARB and Permit Paperwork
Communities in Nocatee, Ponte Vedra, St. Johns and the beaches have architectural review on gutter color and profile. We handle the submittal.
On-Site Fabrication and Install
The roll-forming machine runs 7-inch 0.032 aluminum in continuous lengths at the house. Hidden hangers at 24-inch maximum, drip edge lapped into the trough, 4x5 downspouts set and routed. Our in-house crew does the work; nothing is subcontracted.
Flood Test and Walkthrough
Every run is water-tested from the roof before the crew leaves, and you walk it with us.
Where Metal Roofs Meet Big Rain in Northeast Florida
The beaches and the Intracoastal
Standing-seam roofs are the default on new and rebuilt homes in Jacksonville Beach, Ponte Vedra and Amelia Island, where wind-driven rain and salt air make the fastener spec as important as the gutter size.
St. Johns County and Nocatee
Metal roofs on the larger lots in Nocatee and across St. Johns County usually come with long single roof planes and an ARB that cares what the gutters look like; 7-inch in a matched color reads as premium on these homes.
St. Augustine and the historic core
5V crimp metal is traditional on older homes in St. Augustine and the Jacksonville historic districts, often with half-round or copper gutters; the same sizing logic applies, and copper is available in 7-inch.
Storm country generally
A metal roof is the roof people buy to survive hurricane season. The gutter system should be built to the same standard, which is why 7-inch with 4x5 downspouts is also our hurricane defense spec.
Gutters for Metal Roofs FAQ
What size gutters do I need for a metal roof in Florida?
7-inch K-style seamless aluminum with 4x5 downspouts on most Northeast Florida metal-roof homes. Metal sheds water faster than shingle and the roofs are usually steeper, so the water arrives at the eave at speed and in volume. A 7-inch carries about 22 gallons per minute against 16 for a 6-inch, and the front lip sits far enough out to catch the overshoot. Estate and commercial metal roofs step up to 8-inch.
Can you put gutters on a standing seam metal roof?
Yes, and nothing has to penetrate the panels or the seams. The gutter hangs on hidden hangers or an Alu-Rex continuous hanger screwed into the fascia, and the panel's eave trim is set so it directs water into the trough. Standing seam, 5V crimp and stone-coated steel all take the same fascia-mounted 7-inch system; the only difference is how the drip edge is detailed.
Why does water shoot over my gutters on a metal roof?
Because the gutter is too small or set too far back for the speed of the water. Smooth metal panels on a steep pitch send runoff off the edge in an arc that clears a 5-inch trough and reaches the lip of a 6-inch in heavy rain. 7-inch puts the front lip an inch further out and adds about 40 percent more capacity, which is what stops the overshoot and the trench under the eave.
Do I need 4x5 downspouts on a metal roof?
Yes on 7-inch systems. A 4x5 downspout has 20 square inches of outlet against 12 for a 3x4, and a long metal roof plane can fill a 7-inch trough faster than a 3x4 drains it. The outlet, not the trough, is where most overflow starts. We place the 4x5 outlets by roof plane and route them away from the slab or into underground drainage.
How much do gutters cost for a metal roof house in Jacksonville?
7-inch seamless aluminum is $14 per linear foot installed plus $110 per first-story downspout. A 2,400 to 2,800 square foot single-story metal-roof home with 190 to 240 feet of gutter runs about $3,320 to $4,130; a 3,000 to 3,500 square foot two-story about $5,100 to $6,600. Guards and stainless coastal hardware are added per foot. Every rate is published on our pricing report.
Do gutter guards work on metal roofs?
Yes. LeafBlaster Pro 316 stainless micromesh is made in 7-inch sizing and attaches to the gutter, never under the roof panel, so the roof warranty is untouched. On 7-inch the Alu-Rex option is the single-layer continuous hanger; DoublePro is a 6-inch product. We set the guard angle to the roof pitch so fast water passes through the mesh rather than skating over it.
Will aluminum gutters corrode against a metal roof?
Not when the metals are matched. Aluminum gutters are compatible with galvalume and painted-steel panels, and near the coast we use stainless or marine-grade fasteners so salt air cannot work on the screw heads. Copper gutters are fine under a steel roof because the roof drains onto the copper. The combination we avoid is copper draining onto aluminum.
Quick Answers
Metal roof, right-sized gutters
Pitch, panel type and roof-plane length decide the size, and that takes a tape measure, not a guess. Albert Urbank measures it on site, free, and the written itemized quote is the price the job is installed at.
5.0 stars, 170+ Google reviews | NDS Certified Professional Drainage Contractor | In-house crew, never subcontracted | Seamless 0.032 aluminum | Licensed and insured, locally owned
