How to Install a Half-Round Gutter

Q: I got rid of the rusty old gutters on my 1830s farmhouse. Now I need new ones. What should I replace them with?

Kevin Lyons, Hayden-Lyons Roofs of Distinction, replies: I’d recommend that you install traditional half-round gutters in copper. The style is appropriate to your house, and you’ll never have to worry about the copper rusting.

Hanging them is not hard, as long as you have a helper to lift and set the sections in place. But first you need to size up your situation so that you can order the parts. Ask yourself: What lengths do I need? Will each gutter get one downspout or two? And what about the fascia, where the gutters attach? Is it angled or plumb? Is it even sound? (If it isn’t, repair it.)

When the parts arrive, locate the high point of the gutter’s run—the farthest point from a single downspout or the midpoint between two. Then you can set the pitch, and the rest is all downhill.

Step One // How to Install a Half-Round Gutter

Set The Pitch

At the high point of the gutter’s run, hold a bracket and a section of gutter against the fascia, with the gutter’s outer lip just under the plane of the roof. Make a mark with a pencil for the bracket’s screw hole. Use a water level to make a matching mark at the downspout end. Measure down from that mark, ½ inch for every 10 feet of run, and mark the low point. Snap a chalk line between the high and low marks, and you have your pitch.

Step Two // How to Install a Half-Round Gutter

Attach The Brackets

For best support, screw the brackets to the rafter tails; nailheads on the fascia give away their location. To determine which rafters get brackets, figure that they should be laid out evenly across the span no more than 32 inches apart. Drill pilot holes where the chalk line crosses the selected rafters, then screw the brackets to the fascia. On angled fascia, wedges (shown) make the brackets plumb.

Step Three // How to Install a Half-Round Gutter

Cut The Downspout Holes

Measure in from the end of the roof to the point directly above where you plan to attach each downspout. Typically, they run inboard of corner trim; how far depends on their bracket’s size. Transfer those measurements to the gutter, and cut the downspout holes with a hole saw or with metal shears, as shown.

Step Four // How to Install a Half-Round Gutter

Hang The Gutter

With a helper or two, set the gutter into place on the brackets, taking care not to scratch the soft metal. Hook the back edge to the bracket, then hold down the front edge using spring hooks, screws, or stainless-steel pop rivets (shown).

Step Five // How to Install a Half-Round Gutter

Solder The Seams

On all end caps (shown) and seams, polish the metal with 300-grit emery cloth and brush on flux. Heat each seam with a torch until the flux bubbles, then feed a bar of 50/50 solder onto the hot metal. Once cool, wipe the solder clean.

Step Six // How to Install a Half-Round Gutter

Install The Downspouts

Assemble the downspouts and elbows so that each upper piece fits inside a lower one. Slip the top elbow over the outlet fitting, check that the downspout is vertical, and attach brackets, as shown, near the elbows at the top and bottom.