Especially for people considering a DIY gutter project, the go-to option is often sections of material that join together. There is a sealed seam where each section is joined. A professional installer will most often recommend seamless gutters, which are custom-created to be a specific length of continuous material.
Sectional gutters can easily fail at the seams. Over the years, the repeated expansion and contraction of freeze/thaw cycles can cause the seam to fail, at which point a leak from the seam will be visible next time it rains. At that point, the seam must be repaired or the sections of gutter replaced. Over the years, this maintenance can get expensive.
Seamless gutters eliminate the potential of broken and leaking seams. That means you won’t have to worry about seam maintenance or repair, or seam leaks leading to dripping water, walkway ice and soaked siding. Although seamless gutters may cost a little more upfront, they can save you money over time because of the lack of seams.