How to Extend an Aluminum Downspout

What You'll Need
Downspout the same size as your downspouts
Hacksaw for cutting
Work gloves
Tape measure
Silicone adhesive or liquid solder
Downspout elbow

If you are a homeowner and you seem to be having pooling water in your lawn or a lot of seepage in your basement then you may need to extend your downspouts. Water can be one of the single most damaging elements to your home and even a small amount of seepage into your basement walls and foundation over time can cause foundation structural problems and damage, mold, mildew and will cause sill rot and attract insects.

Determining downspout length

Most engineers and home repair experts agree that water should be channeled a minimum of 10 feet from your home. Some of this depends upon soil type, slope of your lawn and how close you are to other homes. You don't want the water you drain away from your home to flood someone else's basement or to pool in other places on your property.

It is quite simple to add the extension to your downspout. First, measure the distance from the end of your downspout to where you want the water to end up when it drains off. Using the hacksaw, cut your piece of aluminum downspout to that size. Then attach the elbow piece to the downspout that is already on your home with the adhesive or liquid solder material and allow it to dry til it holds firmly. You may also screw this piece into the existing downspout with sheet metal screws. Once this is dry or attached, then attach the extension to the elbow in the same manner. This works well for areas that have little traffic or no sidewalks.

High Traffic Areas

If you need to extend a downspout in an area where there is a walkway or other traffic or obstructions you have a couple of choices. First, you may use a flexible extension that attaches to the end of your downspout. These work on the pressure of the water coming down the spout and the force of it will cause it to unroll. When the rain and pressure stop, the piece will the coil back up out of the way so you won't trip over it. These are available at most large home repair centers.

Another option is to dig in the extensions once they reach ground level. This will require digging trenches to lay the extensions in at a downward sloping 90 degree angle. You then lay the pipe extensions to the area you want the water to be deposited. Some homeowners lay the pipe extensions all the way to the street so they will empty into storm sewers and are then drained away with other water. The pipes should then be covered in soil and grass and plants can be planted as with any lawn. This is a more time consuming and labor intensive fix so you may want to give it some thought if you are a beginner or want to do a quick job.