Seamless aluminum, run to length in your driveway.

A sectional gutter from a hardware store is a chain of ten-foot lengths with a joint every ten feet, and every joint is a place it will eventually leak. A seamless gutter has none. The machine rides in the trailer, the coil goes in one end, and a single length comes out the other at exactly the measurement of that wall. Corners are the only joints, and they are mitred, riveted and sealed.

The part you never see is what decides whether it works: the pitch. A gutter has to fall toward its downspout by a small, consistent amount along the whole run, or water sits in it, freezes in it, and pulls it off the fascia in the spring. Zack sets the line with a level before the first hanger goes in, and the hangers are screwed through the back of the gutter into the rafter tails, not spiked into the trim.

Aluminum comes in a baked-enamel finish in thirty-odd colours, so it can disappear against white trim or read as a dark line under a black roof. Downspouts go where the grading wants them, not where it is convenient, and the old gutters leave in the trailer.