5" vs. 6" Gutters: Which Size Does Your St. Louis Home Actually Need?
When homeowners think about gutters, they usually think about cleaning them — not sizing them. But choosing between 5-inch and 6-inch gutters is one of the most impactful decisions you can make for your home's long-term protection. In St. Louis, where severe thunderstorms can dump over an inch of rain in under 30 minutes, getting this right matters more than most people realize.
What Does Gutter Size Actually Mean?
Gutter size refers to the width of the gutter's opening — the channel that catches runoff from your roof. Standard residential gutters in the US come primarily in two sizes: 5-inch K-style and 6-inch K-style. Both look similar from the street, but they have dramatically different water-handling capacities. A 5-inch gutter handles approximately 1,000–1,200 square inches of roof drainage per section. A 6-inch gutter handles up to 1,600–2,000 square inches — roughly 40% more capacity.
5" Gutters: When They Work
Five-inch gutters are the standard for most residential construction in the US, and they work well in the right conditions. If your home has a low to moderate roof pitch, average-sized roof planes under 1,000 square feet per section, and is in a region with modest rainfall, 5-inch gutters are cost-effective and perfectly adequate. They are lighter, less expensive to install, and easier to find in standard colors and materials. For a straightforward ranch-style home in a lower-rainfall area, 5-inch gutters are completely appropriate.
6" Gutters: Why We Recommend Them in St. Louis
St. Louis sits in a severe storm corridor where summer thunderstorms routinely produce rainfall rates of 1.5 to 2+ inches per hour. At those intensities, 5-inch gutters overflow — even when they are perfectly clean and properly pitched. The overflow doesn't just look bad; it saturates your fascia boards, compromises your foundation, erodes landscaping, and can cause basement water intrusion. Six-inch gutters, paired with 3"x4" downspouts instead of standard 2"x3", move water off your roof and away from your foundation fast enough to keep up with Missouri's storm rainfall. We recommend 6-inch gutters for any home with a steep pitch (6/12 or greater), large roof planes, or a history of overflow during heavy rain.
Does Insurance Cover Gutter Replacement?
Yes — if the damage was caused by a covered storm event. Hail leaves distinctive round impact dents in aluminum gutters that are clearly visible and measurable. Insurance adjusters use gutter damage as one of their primary verification points for hail claims. If your gutters show hail damage, they are typically included in your claim scope. Hail Shield Exteriors documents gutter damage as part of every Pro-Package inspection — including photos, measurements, and impact density per linear foot. We include gutters in our supplement requests to ensure you receive full replacement value, not a patch job.
Seamless vs. Sectional: One More Thing to Know
Most homes built before 2000 have sectional gutters — lengths of gutter connected at joints every 10–12 feet. Those joints are where leaks always develop. Seamless gutters are fabricated in a single continuous piece from end to end, eliminating every joint except at the corners and downspout connections. We install seamless aluminum gutters custom-cut on-site for every project. In our experience, seamless gutters in the right size outlast sectional gutters two to one — and they look significantly better.