Gutter Ratings and Gutter Quality
There are many different types of rain gutters on the market. Unfortunately, no gutter rating system exists, but with careful evaluation of materials, thickness, and other differences between the options, a homeowner can make an intelligent choice.
Gutters come in two main styles: sectional and seamless. Sectional gutters are sold in home improvement stores and can be installed by a do-it-yourself homeowner. Seamless gutters are custom made on site by a roofing professional and therefore cost more to install than sectional gutters (including sectional gutters installed by a professional). More important than cost, though, is the difference between the two in performance. The seam between each section of gutter can be a weak spot that fosters leaks, and drips onto the frame and foundation of a house -- exactly what a gutter is trying to prevent. Seamless gutters limit these weak spots and are more likely to consistently funnel the collected water to the downspouts.
Both sectional and seamless gutters come in different sizes, thicknesses, and shapes which also affect their performance. Most channels are 4", 5", or 6" in diameter; wider channels have larger water capacities and are therefore best for areas of the country with more rain and snow.
Weather is also a factor when considering shape and, especially, thickness. In locations where ice is common, thicker is better (0.32" is the norm). 0.27" thick gutters are often sufficient in less severe climates. Thinner gutters are also available, but are likely to be too weak to handle the required water flow.
The two most popular shapes are U and K gutters (so named because they look like those letters). U gutters need to be an inch larger than K gutters to carry the same amount of water, but some professionals claim U gutters hold up better to snow and other severe weather.
Considerations when selecting gutter material include cost, strength, durability, ease of installation, and aesthetics. Aluminum is the most common gutter material; seamless gutters are almost always made from aluminum and a majority of sectional gutters also use it. It offers a nice compromise between cost and strength plus it doesn't rust.
Other options for sectional gutters include stainless steel, vinyl, galvanized steel, wood, and copper. Wood and copper are both expensive and typically reserved for restoration work, but vinyl and galvanized steel are common in standard home installations. Vinyl is especially popular with do-it-yourself homeowners because the sections snap together without soldering. Unfortunately, vinyl is more brittle than metal and these gutters tend to need replacement faster than other gutters. Another consideration is color; homeowners who want gutters to match a specific shade may be limited in material choice.
Gutters can be fastened to roofs in several ways. Hidden hangers, or hangers that fit inside the gutters and bite into the roof truss, are the most popular fasteners. More traditional spike and ferrule systems are also common but tend to break down faster so aren't recommended for new installations. Strap fasteners that fit over the gutters are also available.
All gutters should be cleaned and inspected twice a year regardless of their construction, materials, or fastener system.