Imagine a heavy downpour: Rain pounds your roof and torrents spill over the eaves. You can’t reach the front door without passing beneath a mini-Niagara. And the basement' Better fire up the sump pump. Get the idea' Before that next storm arrives, it may be a good idea to consider how your house will weather it. This brings us to the subject of gutters.
Granted, gutters aren’t exactly glamorous. But they handle a critical task: routing the runoff from a very large surface—your roof—to proper drainage away from the house. By doing this, they keep your house high and dry, protecting siding, windows, doors, and foundation from water damage. Though most gutters are installed on existing roofs, adding them during reroofing simplifies installation and allows them to be fully integrated into the roof system. If you’re thinking about installing a new roof, your timing couldn’t be better.
Of course, gutters aren’t necessary for every house or every roof slope. Broad overhangs may cast runoff well away from the house, where proper grading and drainage can carry it away. If this is the case with your house, save your money for a different type of rainy day.
If you look under “Gutters” in the telephone directory, you’ll see numerous ads touting “seamless,” “soldered,” “continuous,” “copper,” “sheet metal,” and other varieties. Which ones are right for your house' The following should help you sort through the possibilities.
Rain gutter sizes & profiles. Gutters are formed in several profiles and sizes. The standard profiles are a simple “U” shape and a “K” style, which has an ogee-shaped front, vaguely reminiscent of the letter “K.”
Channels are 4, 5, or 6 inches in diameter; 5-inch K-style gutters are a popular type. Matching downspouts are 2-by-3-inch or 3-by-4-inch rectangular profiles or 3- or 4-inch round (often corrugated) pipes.
The larger systems are generally worth the difference in price because they’re less likely to clog. If trees overhang your house, 3-by-4-inch downspouts are a good idea.
Gutter mounting systems. Gutters are attached along a house's eaves by any of several types of straps, brackets, and hangers, as shown in the illustrations above.
Says one gutter installer, “We primarily use the hidden hanger method because, over the years, as the wood gets a little older, spikes [of a spike-and-ferrule hanger] tend to pull out. 
We screw a hanger to the fascia or rafter tail. When we don’t have that alternative because there are no rafters or no fascia to attach to, we have to use a strap. If we can’t get the strap under the shingles, we encourage the homeowner to wait and install gutters in conjunction with a new roof.”
A crossbar hanger is particularly sturdy. It clips onto the front, goes over the top of the gutter, and clips on the bracket at the back.
Rain gutter buying tips. Anyone who can afford about $20,000 for a seamless gutter machine can start a gutter business, so be sure to check references and get more than one bid. If you’re considering seamless gutters and one bid is considerably lower than another, check the gauge and other details.
Coil stock is sold in several thicknesses, including .032, .027, and .025 inch. Be sure to specify the thicker .032 material. Also ask whether the material is primary or secondary aluminum. Primary aluminum is more likely to be of a consistent quality.
Be sure your contractor will hang gutters along a chalk line, snapped to allow the proper slope of 1/4 inch for each 10 feet toward a downspout. That way, your new gutters will flow properly, look good, and add to the value of your house.
