Quick answer
5 inch or 6 inch gutters in the Tri-Valley: If a clean gutter sheets water over the front edge in a December storm, that is a capacity problem, not a debris problem. A 6 inch gutter carries roughly 40 percent more water than a 5 inch, with larger downspouts to match, and it belongs on runs over 40 feet that cannot take a second downspout, any run over 60 feet, lower gutters catching an upper roof, and inside valleys that overflow. If your run is under 40 feet, has a downspout, takes no upper roof and does not overflow in a real storm, 5 inch is fine. Call (925) 905-9555 or get a free quote online.