What You Need to Know

Heavy rain flowing down house walls to the ground below, can cause a great deal of damage. At the very least, it taxes paint and wriggles into cracks, contributing to eventual, long-term decay. At its worst, it foils windows, invades walls and undermines foundations. Gutters and drainage systems handle rainwater removal to keep these things from happening.

Gutters, long troughs that catch water at the eaves, slope slightly toward downspouts that pipe the water to the ground. Depending upon the drainage situation around the base of the house, water is then routed into below-ground drain pipes or other means of dispersing it away from the foundation.

To catch both runoff and ground water, perforated drain pipe, run in a gravel-filled trench, provides the path of least resistance for water. Pipe drops at a minimum slope of 1/2-inch per foot.

Rain gutter basics

Gutters and downspouts are made from wood, vinyl, and several metals, including aluminum, galvanized steel, stainless steel and copper. Wood gutters are virtually obsolete, except for their use in restoration work. You can buy vinyl gutters at home-improvement centers as do-it-yourself systems; professional gutter installers also install them. Sheet metal shops and gutter specialists make and install most metal gutters.

Before we focus on materials, let's look at a few fundamentals. First, you can buy either "sectional" or "seamless" gutters.

Sectional types are sold or installed as component systems--preformed channels, 10- to 22-feet long, with matching corners, end caps, connectors, drop outlets, downspouts and other fittings. They're made of prepainted steel, galvanized steel, painted aluminum or vinyl. All do-it-yourself gutter systems fall into this category; many professionals install them as well.

Seamless gutters, today's most popular type, are extruded from metal "coil" stock, using a special machine that's brought to your home by a gutter fabricator. As their name implies, they don't have potentially leaky seams along their lengths--their biggest selling point. The lengths join to inside and outside corner components and downspout outlets. Seamless gutters are usually formed from aluminum that has a baked-on finish, but they may be made from copper or factory-painted steel.

Rain gutter sizes and profiles

Gutters are formed in several profiles and sizes. The standard profiles are a simple "U" shape and a "K" style, which has a 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 3 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.

A matter of metal

Aluminum and steel are the two most common professionally installed gutter materials. The one that is best depends on your situation. Major plusses for aluminum gutters are that they're relatively inexpensive and will never rust. Steel gutters are sturdier; this isn't necessarily an issue unless you'll be leaning ladders against the house for access to the roof or live where high winds, trees, or other factors may cause wear and tear. Most homeowners opt for seamless aluminum. Aluminum is available in over 20 different colours. Prepainted steel is available in 6 colours

Copper rain gutters

Most people agree that copper makes the ultimate gutter: handsome, with a natural patina that ages to a verdigris color. It doesn't require any finish. It will last as long as the house because it doesn't rust.