Add a surface extension
Step1
If foundation plantings or ground cover camouflage the downspouts, add a length of horizontal downspout, PVC or flexible drainpipe to the bottom of the existing downspout to extend it at least 5 to 6 feet (1.5 to 2 m) away from the house.
Step2
If necessary, drive downspout-extension stakes into the ground to support and hold metal extensions in place, and place a rock or concrete splash block at the end to reduce soil erosion (see A).
Install a manual hinged extension
Step1
You can make a hinged extension, which tilts up and out of the way when not in use (see B). Remove the elbow (if any) at the bottom of the downspout.
Step2
Cut the end off a length of downspout at a 45-degree angle using a hacksaw with a fine-tooth blade.
Step3
Join the cut end to the bottom of the downspout with a hinge. Drill pilot holes for 1/4-inch (6-mm) aluminum sheet-metal screws or rivets.
Step4
Alternatively, you can purchase a kit that has the hinge already riveted to two short lengths of downspout, which just slip into or over your downspout and extension. Or purchase a preassembled extension with a hinge and a short section that slips over your downspout. In both cases, secure the connections with 1/4-inch (6-mm) aluminum sheet-metal screws or rivets installed in drilled pilot holes.
Install an automatic extension
Step1
Installation procedures vary with the system, but typically you must shorten the downspout. You can do so with the downspout in place, or remove and reinstall it. Slip the downspout into the end of the extension device.
Step2
Mount the device to the wall with screws as directed by the manufacturer. For stone, brick and other masonry walls, drill a hole for masonry anchors that will accept the mounting screws. The weight of the water collecting in the extension eventually lowers it to the ground, and it springs back up slowly as the rain stops.
Install an underground extension
Step1
Use a digging shovel with a long handle to dig a trench for an underground pipe, the Cadillac of downspout extensions.
Step2
Put an elbow and a drain adapter on the house end of a 4-inch (10-cm) PVC or flexible drainpipe. Connect it to the downspout, extending one or the other as needed.
Step3
Insert the other end into a catch basin or surface bubbler. The bubbler's grate (green, brown or black) lies flush with the surface and allows water to spill harmlessly on the ground.
Step4
Alternatively, direct the pipe into a gravel drywell (see C). Dig a hole at least 4 feet (1 m) deep, line it with landscape fabric and fill it with gravel to within 1 or 2 feet (30 to 60 cm) of the surface, embedding the pipe near the top. Cover with more fabric and then topsoil.