How to install gutters
Gutters come in several different sizes, although most people never realize it. You may have gotten used to seeing white and brown gutters on homes, but in fact, there are many custom colors available today. I built a Navy barracks in New York that required all the red trim. The blinds, vents, fascias, and soffit materials, and yes, even the gutters and downspouts were the same red color. As with window units, there are dozens of custom colors to choose from today.
Nearly all residential applications use a standard four-inch by four-inch wide gutter and three-inch downspouts or runners. There are cases where due to the large expanse of roof area, a larger gutter may be required. Five-inch gutters are available that resemble the standard four-inch size. Downspouts are increased from three inches to four inches to accommodate the additional water flow. If the downspouts are too small, water will spill over the outside edge of the gutter, defeating the entire gutter intent and possibly damaging the home or landscape below.
Gutters called “Yankee Gutters” are also available. These are integrated into the roof itself and do not protrude from the edges of the roof. Often used in the New England area, rumored to help prevent snow slide damage, they became Yankee Gutters. These work extremely well and can be up to twelve inches wide to catch all the water from the roof. However, they must be maintained to prevent leakage. Leaks will go directly into the house since the gutter is inside the exterior wall line. Properly installed and maintained through proper cleaning, these gutters have lasted for over a hundred years.
All gutters have downspouts of some kind. These come in ten-foot straight lengths, as well as Type A and Type B elbows. Color-matched gutter straps are also available. Downspouts must be securely secured to the house, as falling water places a heavy load on pipes and fixtures and can actually dislodge a downspout from the gutter or house.
Once I have the downspouts in a finished configuration that I like, I rivet each pipe and splice together with two rivets of the same color. The additional rivets used to secure the straps to the guide tube leave an attractive final product that will not separate.
It is also important to a good gutter system to provide a way for water to exit the end of the downspout and away from the home’s foundation. There are commercial products that hold the end of the downspout which deploys when the water in the leader puts enough pressure on the inside of the coil. The plastic roll has holes to act like a sprinkler hose, allowing the water to come out slowly and not damage the plants or grass below.
There are many types of gutter accessories on the aftermarket to keep leaves and other debris from getting into gutters and clogging them. Gutters should be cleaned at least once a year to prevent debris from clogging downspouts and causing gutter overflows. There are also some pretty good washer attachments that fit on the end of a garden hose that will allow you to wash down gutters in the ground or up a small ladder. There are many types of leaf guards that fit inside the upper lips of the gutter to prevent leaves from entering the gutter. Some work quite well, others not at all.
There is a type of “gutter” system that is actually not a true gutter at all. These are called rain guards, rain sprinklers, etc. They are a series of finned sections that in cross section look like a blind lamella. When rainwater flowing from the roof hits the guards, the guards spread the water over a large area, thus dissipating the force of the water falling directly onto the ground below the eave edges. However, they do not direct water away from the foundation, which must be considered before installing them.
Precast gutter sections come in ten foot lengths. If you need a longer gutter, you should use a gutter fitting and caulk to seal them. These splices tend to warp and leak over time, so you should seriously consider having a one-piece gutter made for you. Gutter companies will come to your house and, using a special machine on a trailer, will roll out the gutter to the length you need in one piece. They can also install the end caps and outlet. Trying to manage a twenty, thirty or forty foot gutter is not an easy job by any means. If you purchase the gutter and decide to install it yourself, remember that if it bends or twists during installation, you own it. A very good idea is to have the contractor install it for you.
If you decide to install a gutter yourself, anything over ten feet is a two man job in almost all cases. You will need ladders, a hammer, a tape measure, a four-foot level, a drill with metal bits, rivets and a rivet gun, gutter caulk, gutter spikes and ferrules, or roof gutter straps. I drive a nail every two feet in the center starting a couple inches from the ends and over the downspout exit openings. Install both end caps with caulk first, and then add the downspout outlets, riveting each into place. If you are using a single ten foot gutter, a downspout at one end should be more than enough. Gutters can be hung with nails and ferrules or with roof straps. A newer mount fits inside the gutter, clips onto the gutter lips, and screws into the fascia with a power drill. This type leaves no exterior evidence of mounting. If you are using bits and sockets, placing sockets inside the lips of the gutter. Place a spike on the outside face of the gutter directly over the gland opening. Hitting the dowel with enough force will pierce the gutter and into the ferrule. Align the gutter exactly where you want the finished elevation to be and drive the dowel through the back of the gutter and into the front panel. Do not drive the tines in all the way. Continue along the gutter in incremental two foot spaces until you reach the opposite end of the gutter.
Get off the ladder and look at the gutter. Does it lean slightly towards the downspout hole? If it’s really noticeable, it may be too much lean. Now is the time to adjust the slope of the gutter before driving the nails fully into the wood. If you’re happy with the gutter, go ahead and set the tines flush with the gutter, but don’t compress the gutter or ferrules. The spikes come in pre-finished head colors of both white and dark brown to match the gutters.
Roof straps are for me the least desirable mounting method. They are used when the fascia board is weak or non-existent. The purlin is nailed to the roof below the bottom tile and hangs over the edge of the eave. The chute is placed inside the belt assembly and the belt snaps into place. I have seen these straps driven into the bottom of the shingles but this is highly undesirable and will surely leak as the year goes on.
Once the gutter is mounted, you can proceed to install the downspouts. Downspout fittings come in so-called Types A or B. Both are about 45 degree elbows, but one is flat and the other is curved. Using combinations of solid downspout pipe and fittings, build the entire downspout in one piece on the ground using trial and error fittings. You can bend your elbows slightly and use the left and right attachments to clear other obstructions until you have a finished length of downspout that will carry the water directly to the ground or splash block below.
Attach the downspout to the gutter outlet with two small galvanized sheet metal self-tapping screws. You may want to remove the downspout to clean it some day. Now, using the downspout bracket that you riveted to the pipe earlier, bend the flat bracket tightly around the downspout and fold the two ends out against the siding of the house. Using galvanized roofing nails, nail the straps securely to the main building. A minimum of two straps are required, one at the top where the downspout first contacts the house and the other just above the bottom elbow. Pull the downspout. Remember that many pounds of water will flow through this pipe at the same time during a storm and in winter areas, freezing rain or ice can freeze solid in the pipe. If the wall brackets are not nailed correctly or not enough straps are used, the downspouts will surely fail.
Lastly, a good investment is to place under-outlet backsplash blocks at the bottom of each downspout. Even if the downspout exits an asphalt or concrete driveway, use a splash block. Concentrated water from a downspout will quickly damage your driveway or patio surface. The splash block helps direct water away from the foundation and also prevents soil erosion next to the foundation. Backsplash blocks are available in concrete, plastic, and fiberglass. They all work well so the decision on your part is the price and the final appearance.
I avoid gutters unless absolutely necessary or a building code is required. A door at the end of the eaves of a building requires a gutter over the door. Does not require a gutter along the entire length of the building. Gutters trap leaves and other debris, cause ice dams in snowy areas, and need constant cleaning. I avoid them whenever I can.
Good luck with your gutter installation.
Pete
Your friendly building inspector
http://www.wagsys.com
BICES-Building Inspection and Code Compliance System Software