The gutter itself
The gutter (or trough) is the channel along the roof edge. On most homes it is a seamless aluminum K-style gutter formed on site from a coil, in 5-inch or 6-inch sizes. Half-round gutters are common on older and high-end homes. The size refers to the width across the top. Larger gutters hold more water and are less likely to overflow in heavy rain. See 5-inch vs. 6-inch gutters and half-round vs. K-style gutters.
The gauge or thickness matters as much as the size. Thicker aluminum resists dents from ladders, hail and ice better than thin material. Quotes should state the thickness, for example .027 or .032 inch.
End caps
An end cap closes each end of a gutter run. It is crimped or riveted into place and sealed. Leaking end caps are one of the most common gutter problems, usually because sealant has aged or the cap was not fully seated. Good installers seal end caps from the inside with a gutter sealant rated for the material. See fixing leaking gutter seams.
Miters (corners)
A miter is a corner piece where two gutter runs meet. Inside miters sit where two walls form an inside corner, often below a roof valley; outside miters wrap around outside corners. Miters can be factory-made strip miters or box miters, or cut and folded on site. Because every miter has seams, corners are a common leak point. Inside corners also collect the heaviest flow from roof valleys and often need a splash guard. See roof valleys and gutter overflow.
Outlets (drops)
The outlet, also called a drop or downspout outlet, is the short tube attached to a hole cut in the bottom of the gutter. It connects the gutter to the downspout. The outlet size should match the downspout: 2x3-inch or 3x4-inch rectangular, or round. A larger outlet drains faster; a clean, well-sealed outlet is one of the cheapest ways to reduce overflow. Outlets should be sealed from the inside so water does not leak around the flange. See downspout size and placement.
Hangers
Hangers hold the gutter to the fascia. Hidden hangers clip inside the front lip of the gutter and screw through the back into the fascia; they are the most common choice on seamless gutters. Older systems used spikes and ferrules, which loosen over time. Spacing matters: closer spacing supports snow, ice and heavy rain better. See gutter hangers explained and sagging gutters.
Drip edge and gutter apron
Drip edge is a metal flashing at the roof edge that directs water off the roof and into the gutter instead of behind it. A gutter apron serves a similar purpose where drip edge is missing or too short. Both are roofing parts, but they matter for gutters. See drip edge and gutter apron.
Downspouts
The downspout (or leader) carries water from the outlet down the wall. Common sizes are 2x3 inches and 3x4 inches rectangular, or 3- and 4-inch round. A 3x4-inch downspout carries considerably more water than a 2x3-inch one, which is why upgrading downspouts is often the best overflow fix. See gutters overflowing in heavy rain.
Elbows
Elbows change the downspout’s direction. Two elbows near the top bring the downspout from the outlet, which sits out from the wall, back to the wall; another elbow at the bottom turns the water away from the house. Elbows are where clogs most often form, because debris catches on the bends. They also come in A and B styles, which turn in different directions, so the installer needs the right combination for each corner.
Straps and brackets
Downspout straps or brackets fasten the downspout to the wall. A strap at the top, at every joint and near the bottom keeps downspouts on the house in wind and prevents joints from separating. On stucco, brick and siding, straps must be fastened and sealed correctly. See gutters and stucco homes.
Leader heads and conductor heads
A leader head (or conductor head) is a box at the top of a downspout that collects water from a gutter or scupper. Decorative copper leader heads are common on historic homes; plain ones are used where flat roofs drain through scuppers. See gutters for flat roofs and scuppers.
At the bottom: extensions, splash blocks and buried lines
Water leaving the bottom elbow needs somewhere to go. Extensions (fixed, flip-up or roll-out) carry it several feet from the foundation. Splash blocks are concrete or plastic pads that spread it out. Buried lines carry it underground to a pop-up emitter, a dry well or a curb outlet where allowed. See downspouts and your foundation and underground downspout drainage.
Accessories
- Gutter guards cover the top of the gutter to keep debris out. See are gutter guards worth it?
- Downspout strainers sit in the outlet to stop debris entering the downspout. See downspout strainers and leaf catchers.
- Splash guards at inside corners stop water from shooting over the gutter.
- Rain chains replace downspouts for appearance. See rain chains vs. downspouts.
- Heat cables reduce ice in cold climates. See heat cables for gutters.
Sealants and fasteners
Sealant at end caps, miters and outlets keeps seams watertight. Fasteners should be compatible with the gutter metal: aluminum gutters with aluminum or stainless fasteners, copper with copper or stainless. Mixing metals can cause corrosion. Rivets, not just screws, are typical at miters and outlets on quality jobs.
Reading a quote
A good quote lists the gutter size and thickness, total feet, the number and size of downspouts and outlets, hanger type and spacing, miters, extensions or other discharge, guards if included, removal of the old system and fascia repair pricing. If a quote lists only a total price, ask for the details. See how to compare gutter quotes. For payment terms, see paying for new gutters. For roofs where an upper section drains onto a lower one, see upper-roof downspouts onto lower roofs.