A.   General Information
         A good gutter system prevents damage to your siding, foundation, and landscaping and helps prevent water buildup in your basement. When gutters fail, you have to evaluate the type and extent of the damage to pick the best repair method. Watch for signs that your gutters or downspouts may be clogged, and clean them as often as needed to keep the system working well.
Use a trowel to remove leaves, twigs, and other debris. Flush out clogged downspouts with water pressure.

B.   Repair or Replacement
         Wrap a large rag around a garden hose and insert it in the opening of the downspout. Arrange the rag so it fills the opening of the downspout, containing the water and concentrating its pressure against the clog. Turn on the water full force. When the clog breaks up, water will gush out the bottom of the downspout.

Check the slope of gutters with a level, and adjust hangers, if needed. Gutters should angle toward the downspouts so water travels freely rather than standing in the gutters, promoting rust. Shield gutters with mesh gutter guards that match the size and style of your gutters. This will prevent clogs in the future.

Rehanging sagging gutters is a common gutter repair. Start by snapping a chalk line that follows the correct slope (usually about ¼" per 10 feet toward the downspouts). Remove the hangers in and near the sag, and lift the gutter until it's flush with the chalk line. Reattach the hangers, replacing them if they're rusty or in bad condition. Shift their location slightly to avoid using the original nail holes. Add hangers, if needed, to place one at least every 2 feet, and within 12" of every seam. Now, evaluate the type and extent of gutter damage to pick the right repair method.

Small leaks and minor damage can often be repaired with easy-to-use gutter repair products. To fill small holes and seal minor leaks, use gutter caulk. It is resistant to the elements and flexes without losing its seal. Use a gutter patching kit to make temporary repairs to gutters with minor damage. Read the manufacturer's recommendations and directions before buying and using repair products.

If you have a leaky gutter joint, you have to first disassemble it by drilling out rivets or removing metal screws. If you're working with downspouts, you might have to take apart the whole downspout to reach the damaged joint. Scrub both parts of the joint with a stiff-bristled brush. Clean the damaged area with water and let it dry completely. Apply caulk to the joining parts, then reassemble and secure the joint with new fasteners.

         To prevent corrosion, patch gutters with the same type of metal that they're made from (usually aluminum or galvanized steel). To patch a metal gutter, first clean the area around the damage with a stiff-bristled brush. Scrub it with steel wool or an abrasive pad to loosen residue, then rinse it with water. Apply a 1/8"-thick layer of roofing cement evenly over the damage, spreading the roofing cement a few inches beyond the damaged area on all sides. Cut and bend a patch from a piece of flashing and bend it to fit inside the gutter. Bed the patch in the roofing cement, and feather out the cement so it won't cause significant damming.

For roof gutters, the best option is a seamless system consisting of continuous lengths instead of multiple sections attached together. When you order seamless metal gutters from a fabricator, make sure the lengths extend slightly past the fascia, aligning with the shingle overhang. At the fascia's midpoint, measure down from the drip edge and make a mark for the bottom of the gutter. Mark both ends of the fascia, adding a ¼" slope for every 10 feet of gutter. Snap chalk lines between the marks.

Mark the downspout locations on the gutter. Set a gutter outlet at each mark, centered from front to back, and trace around it. Cut out the hole using aviation snips. Apply a bead of sealant under the lip of the outlet. Place the outlet in the hole in the gutter. Press firmly in place, then attach from the bottom side of the gutter, using zip screws.

Place an end cap over the end of the gutter. Drive zip screws through the flange into the gutter. Apply ample sealant along the inside edges of the cap. Apply a small bead of sealant on the bottom and sides inside a corner box. Slide the end of the gutter inside the box. Fasten the gutter and box together, using zip screws. Apply ample sealant along the inside seam.

Clip gutter hangers to the gutter every 24". Lift the gutter into place, sliding the back side under the drip edge and aligning the bottom with the chalk line. Drive the nail or screw in each hanger through the fascia to install. Fasten an elbow to the gutter outlet, driving a zip screw through each side. Hold another elbow in place against the house. Measure the end for overlap. Cut a downspout to this length, using a hacksaw. Crimp the corners of the downspout for easy insertion and fasten together.

Fasten downspout brackets to the wall for the top and bottom of the downspout, and every 8 feet in between. Cut a downspout that spans the height of the wall, and attach it to the elbow at the top. Install another elbow at the end of the downspout. Fasten the brackets to the downspout.