We are often asked to repair leaks that may appear to be coming from a gutter, but are in fact roof issues.
Gutters are generally the lowest point on a roof edge, so any water leaking from higher up the roof, will travel down to the lowest point to drip. This can cause a leak to appear to be coming from the gutter, but it is really just following the gutter to a low spot before dripping off.
The most common area where we see this, is when a gutter butts into a wall. If the roofer installed sidewall flashing is not correctly located and sealed, water will leak between the gutter and siding or it can leak behind the siding and into the wall, creating a much larger problem.
Another clue that you may have a roof issue, instead of a gutter leak, is if water is leaking between the gutter and fascia board. Generally seamless gutters do not leak in the middle of the run, this is usually an indicator that water is not being correctly directed into the gutter by the drip flashing.
If water is pouring over the front edge of your gutter, the most likely cause is that you have a clog. Gutters are designed to be lower on the front edge than the back edge, so that if they do fill up with water, it will pour over the front and not back into the soffits.
These are a few indicators that, if familiar with them, can lead you to the source of your leak and the appropriate action to correct it.