For most average-sized homes—whether it’s a simple ranch or a standard two-story—5-inch K-style gutters are the go-to choice. They are the most common style because they look like decorative trim rather than industrial pipes, so they blend right into your roofline. They are built to handle the typical amount of rain most houses face, making them a reliable, "just right" fit for the majority of residential neighborhoods.

While the 5-inch gutter is the standard, you might need to move up to 6-inch gutters if your home has a very steep roof or "valleys" where two roof sections meet and dump a massive amount of water into one spot. Think of it like a funnel: if the water is coming down faster than a 5-inch gutter can drain it, it will simply overshoot the edge and pool at your foundation.

Moving up to a 6-inch system increases water capacity by about 40%, which is often necessary for:

• Large, steep roof surfaces that catch more wind and rain.

• Houses with complex rooflines that create heavy "waterfalls" in certain corners.

• Commercial buildings or very large two-story homes with long gutter runs.