Place downspouts in areas with the least amount of obstructions electrical wires hose bibs sidewalks etc.
Gutter leaking behind gutter.
If you can t see anything with your naked eye you can also try pouring water into the gutter and then making a note of every spot where it leaks out.
Water leaking in behind the facia of your roof could be caused by a couple of things.
On some homes water tends to drip behind the gutters down the fascia and soffit and then either down the side of the house or straight to the ground.
If you re not closely attuned to the behavior of your home s water drainage system you may not notice this occurrence.
Capillary action is a water activity in which water adheres to a surface and follow the surface around.
If your gutters are fastened with spikes and some spikes are loose or rusted simply hammering the spike back in isn t.
When the roof shingles do not extend past the metal drip edge the water will suck back on the metal drip edge this is called capillary action and run behind your gutters.
There should be no more than a inch drop in the direction of the downspout.
Should you notice the gutter leaking in one or a few small ish spots you ll want to carefully inspect the area to see if you can spot either of these problems.
1 your roof sheets have a hole in them or your screws or nails or equivalent are not watertight anymore or 2 the more common reason is where roof sheets are cut too short or they don t overhang far enough into the gutter.