There are a few elements that come into play that cause water to run behind the gutter.
Water dripping from behind gutter.
The first cause is when the roofing material is installed many roofers will not extend the roofing material past the roof edging or drip edge.
Ever wonder why that is.
If the under felt has receded and the felt is not running into the guttering carrying the water from the roof to gutter you will need to fit plastic support trays remove bottom row of tiles fit support tray under existing felt and into gutter this will cure your problem.
If the gutter is clogged some of that water will back up on the roof soaking it.
If you re not closely attuned to the behavior of your home s water drainage system you may not notice this occurrence.
If water is dripping behind your gutter it s probably because it was installed without any flashing over the back of the gutter.
For example most ranch style homes have a 3 12 or 4 12 pitch roof.
Over time rain gutters often start to pull away from the roof allowing water to drip over the gutter sides or between the gutters and the walls.
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.
And it doesn t stop there.
Are you getting water behind your gutter.
Usually this is due to gutter fasteners rusting.
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.
Home centers sell a gutter apron in 10 ft.
Left long enough the water runoff will cause damage to the roof shingles as well as your home s facade.
Capillary action is a water activity in which water adheres to a surface and follow the surface around.
Some of the water may leak behind the gutters down towards the soffit and the fascia.
The gutter apron will prevent the dripping.
Many of the solid gutter covers are design to take advantage of this water characteristic.