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5 inch vs 6 inch Gutters
Holda’s Gutter Size Guide With Costs & Real-World Tips

5 Inch vs 6 inch Gutters

Proper gutter sizing is crucial for managing rain effectively, protecting your home from water damage, and extending the life of your roofing, fascia/soffits, and foundation. This guide explains what really matters—capacity, speed, downspouts, materials, measurement, cost—and when to choose standard 5″ gutters versus oversized 6″.

Professional Gutter Installation: Our Process

While DIY gutter projects most often involve assembling gutter systems from sections bought at Home Depot or Lowe’s, professional gutter installation is different. We purchase gutter coil and accessories, then load the coils onto our machine in our trailer, either at our shop or the supply house. We then bring these materials to your home and fabricate the seamless gutters on-site, custom-cutting to the exact lengths needed for your house. This can add to both aesthetics and functionality.

Why Gutter Size Matters

Here’s the difference you can picture right away: a 5″ gutter holds about 1.2 gallons of water per foot, while a 6″ gutter holds roughly 2.0 gallons per foot—that’s 67% more capacity. On a 30-foot stretch in a heavy rain, that’s 36 gallons vs. 60 gallons. More capacity means fewer spillovers, less streaking on your siding, and better protection for your landscaping and foundation.

Gutters don’t “waterproof” a roof—roofs are built to shed water. Problems show up when water hits the gutter faster than it can be caught or drained: spills over the front, or ponds in the trough. That’s when you see soffit/fascia rot, siding streaks, landscape washouts, and foundation splash/erosion.

Two truths that drive most outcomes:

  • Bigger catch window = more control. A 6″ profile’s wider mouth and taller front edge buy time before water crests during short, intense bursts.
  • Drain path must keep up. Even the right gutter fails if outlets/downspouts can’t move water away fast enough—plan for adequate outlets and use 3×4″ downspouts.

The Simple Physics Behind Overflow

  • Velocity matters. Steep roof planes and metal sections (e.g., standing-seam porches) accelerate runoff; water arrives with more speed and momentum.
  • Pitch prevents ponding. Each run needs a consistent fall toward outlets; flat spots hold water and trigger over-the-front spill at the low end.
  • Outlet density breaks up the load. Long or complex runs often need two outlets so the middle doesn’t pond. Place outlets near valleys/high-catch areas.
  • Downspouts set the throughput. 2×3″ downspouts can choke flow; 3×4″ move water out as fast as it arrives and reduce backup.
  • Smooth transitions help. Clean returns/elbows and secure hangers maintain flow and keep the lip from sagging, which otherwise invites overshoot.

Critical takeaway: Treat gutters as plumbing for rain—catch window + pitch + outlets + downspouts + clean transitions. If any link is undersized or poorly executed, overflow shows up at the ground.

Where 6" Gutter Proves Its Value

  • Long, steep main roof planes (the primary elevations).
  • Any metal sections (porches, accent roofs) that accelerate water.
  • Homes with gutter guards or pronounced shingle overhangs (reduced opening).
  • Curb appeal: 6″ visually matches a common 1×6 fascia and often looks “right,” covering trim and cleaning up sightlines.

When 5" Gutters Can Work

  • Low-slope, short runs with calmer flow.
  • No metal roof sections feeding that run.
  • Minimal edge loss (no guard or shorter shingle overhang).

You can “get away with” 5″ in select spots, but 6″ remains the safer, future-proof choice for the whole home—especially if you’ll add guards later or already have steep planes.

Case Study: Upgrading to 6-Inch Gutters

A Success Story of Solving Overflow Issues

Downspouts: The Underrated Decision

We recommend that you choose 3×4″ downspouts as a go-to. These downspouts move water out faster (resulting in less backup), look cleaner on most homes, and the upgrade from 2×3″ typically runs ~$50 in materials per job, which is small money for a big improvement.

Smart placement, simple rules:

  • Put at least one downspout per long run, at or near the low end of the pitch.
  • Add an outlet near valleys and other high-catch areas.
  • For long or complex runs, use two outlets to prevent pooling in the middle.
  • If you install 6″ gutters, pair them with 3×4″ downspouts so the added capacity doesn’t bottleneck at the outlet.

Looks & Fit

Fascia boards are commonly 5.25″–7.25″ tall. A 6″ gutter (about 5″ tall) often matches proportions better than a 5″, covers more trim, and boosts curb appeal—especially on newer homes with larger fascias and bolder elevations.

5 Inch vs 6 inch Gutters

Materials at a Glance

  • Aluminum: Lightweight, rust-proof, the most common residential choice.
  • Vinyl: Inexpensive, corrosion-resistant (more DIY; expands/contracts).
  • Steel: Strong; needs maintenance to prevent rust.
  • Copper: Premium, long-lasting, develops a patina.
  • Zinc: Durable, patinas nicely; higher cost.

Gutter & Downspout Sizes

  • K-Style Gutters: Common in 5″ and 6″.
  • Half-Round Gutters: Standard sizes 5″ and 6″.
  • Downspouts: 5″ K-style typically uses 2×3″ or 3×4″; we recommend 3×4″ for throughput and looks.

Measuring in Linear Feet

When planning for new gutters, it’s important to measure the length of your roofline in linear feet. This measurement helps determine the total length of gutter required. Accurate measurements ensure you purchase the right amount of material and avoid shortages or excess. We often take measurements from satellite imagery for an accurate read.
Here’s how to measure your gutters:
  1. Use a Measuring Tape
    Extend a measuring tape along the edge of your roofline, from one corner to the other
  2. Account for All Sides
    Include all sections of your roof where gutters will be installed.
  3. Include Downspouts
    Measure the height from the gutter to the ground for downspout placement.
  4. Count the Corners, End Caps, and Elbow Pieces
    Record the number of end caps, specifying how many are right ends and how many are left ends. Additionally, count the corner pieces and the elbow pieces needed for your downspouts.
5 Inch vs 6 inch Gutters

Pricing

  • 5″ K-Style aluminum seamless gutters currently run around $16/ft.
  • 6″ K-Style aluminum seamless gutters currently run approximately $18/ft.
  • Accessories needed can significantly impact pricing: downspouts, box miters, etc.
  • Complexity of the building, pitch of roof, existing gutter materials (depending on material used, can be complicated to remove), type of shingles, etc. can all also impact pricing.

Simple example:

  • A home with 180 LF of 6″ gutter at $18/LF ≈ $3,240 for troughs.
  • Add 3×4″ downspouts, outlets, elbows, and miters (quantity varies by layout).
  • Steeper pitches and more corners increase both parts and labor.

Cost reality:

  • 5″ may save about $1 per linear foot.
  • Upgrading 2×3″ → 3×4″ downspouts is typically ~$50 in materials per job.
    Given total project costs, these savings are small compared to the performance gains of a right-sized system.

Case Study: Upgrading to 6" Gutters in Barrington Hills, IL

We upgraded a newer home (3–4 years old) from 5″ to 6″ oversized gutters, improved the pitch, and installed larger 3×4″ downspouts to fix overflow. The home had a steep main roof and a standing-seam metal porch: classic high-velocity trouble spots where water shot past the 5″ front edge. The 6″ system created a wider “target” and, with bigger downspouts, moved water out quickly. (Install day even featured a surprise guest: a little turtle headed to the family pool—caught on video!)

In this video, we showcase a complete gutter installation project in Barrington Hills, IL, where we upgraded the home’s gutters from 5″ to 6″ oversized gutters with improved pitch and larger downspouts to fix overflow issues. Along with highlighting our expert installation process, the video features a fun moment with a surprise guest—a little turtle making his way to the family’s pool!

Installation Quality: Non-Negotiables

Even the right size fails if these basics aren’t done well:

  • Seamless fabrication on site for exact lengths (no piecing).
  • Correct pitch toward outlets—no ponding.
  • Enough outlets/downspouts for each run (avoid long, single-outlet stretches).
  • Hanger spacing: Use heavy-duty hidden hangers every ~24–32 inches, closer in high-snow/wind areas, and at each end/corner to prevent sag.
  • Clean transitions at returns and elbows to avoid turbulence.
  • Smart guard selection/placement that doesn’t choke the opening.

To Keep It Simple: Right size, right pitch, the right number/placement of outlets, and 3×4″ downspouts—miss any one and the system can still overflow.

Quick Decision Tool (Checklist)

Even the right size fails if these basics aren’t done well:

If you answer “Yes” to any of the questions below, pick 6″ gutters + 3×4″ downspouts.

  • Steep main roof plane? → Yes → 6″
  • Any metal (standing-seam) sections? → Yes → 6″
  • Gutter guards now or soon? → Yes → 6″ (edge loss)
  • Long runs or big catch areas? → Yes → 6″ (plus 3×4″)
  • Want better curb appeal/fascia coverage? → Yes → 6″

If every section is short and low-slope, with no metal roof areas and no gutter guards (i.e. a shed), a 5″ gutter can work.

That said, we still recommend 6″ gutters for extra storm capacity and future-proofing (especially if you might add guards later).

Final Recommendation

  • Make 6″ gutters with 3×4″ downspouts your default choice.
  • Use 5″ only on select low-slope, short runs with gentle flow—and understand you’re accepting less margin.
  • If you have (or plan to add) guards, any metal sections, or steep slopes, choose 6″ without hesitation.
  • Treat the gutter as a system: size + pitch + outlets + downspouts + guards. One weak link = overflow.

Have Questions?

Selecting the right gutter size is essential for protecting your home and keeping water where it belongs—away from your siding, trim, and foundation. If you’d like a professional assessment or a quote tailored to your home, contact us. We’ll review roof pitch, catch areas, aesthetics, and budget, then recommend a system that performs in real weather—not just on paper.

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