Seamless Gutters5 min read
5-Inch vs. 6-Inch Gutters: Sizing for Reno Roofs
Gutter size depends on roof area, pitch, and how water collects, not on the size of the house. Here’s how we decide between 5" and 6".
Reno only gets about seven inches of rain a year, so it’s tempting to think any gutter will do. The problem is how the water arrives. Summer thunderstorms can drop a lot of rain in a few minutes, and spring snowmelt sends a steady stream off the roof for days. A gutter that’s too small overflows at exactly the wrong time.
What decides the size
- Roof area draining into each run, not the home’s square footage
- Roof pitch: steeper roofs shed water faster and can shoot it past a small gutter
- Valleys, where two roof planes send their water to one spot
- Run length and how many downspouts the run can have
- Snow load and how much weight the gutter needs to carry in winter
When 5" is enough
Most single-story ranch homes and tract homes with moderate pitch do well with 5" K-style gutters and 2x3 downspouts, as long as downspouts are placed so no run carries too much water.
When we recommend 6"
We usually recommend 6" gutters with 3x4 downspouts on two-story homes with large upper roofs, steep pitches, long runs, roofs with valleys over entries, and commercial or multi-family buildings. The larger trough also gives pine needles and snowmelt more room before anything spills over.
Downspouts matter as much as the gutter
A big gutter with too few downspouts still overflows. Adding a downspout, or upsizing the existing ones, is often the cheapest way to fix a gutter that spills over in storms.