1.  Joints

Each elbow should have 1 screw in the seam which is not showing, total unseen screws should be four. Straps should have at least a 1-1^1/2" wall mount strap and 2 side screws on each strap. Two straps per down spout on 1 story.  Two story houses require 3-4 and up with the increase of height.
(see diagram 3b)  All screws should be pre-painted.  See diagram 3c for improper installation.


2.  Colors

Your downspouts should match the corner boards on your house. If the lower portion of the house has brick, stone, or a different color wood, a 2nd color may be required.

3. How many should I have?

Downspouts should be every 35 ft or less depending on the length of the run. If you have a house with lots of corners it's a smart choice to have them closer.
Remember the water has to run through the gutter and over a lump or bead of caulking on every corner just to reach the downspout.