Water leaking in behind the facia of your roof could be caused by a couple of things.
Water leaking between gutter and fascia.
Usually this is due to gutter fasteners rusting.
Gutters are supposed to direct water away from your roof and into the ground.
Capillary action is a water activity in which water adheres to a surface and follow the surface.
If you re not closely attuned to the behavior of your home s water drainage system you may not notice this occurrence.
The gutter apron will prevent the dripping.
As i only moved in recently i don t know how long fascia and flashing were installed.
I had a look and think the problem is due to flashing being receded.
Home centers sell a gutter apron in 10 ft.
Assuming the gutters have the correct slope the main reason for overflows is that the gutters are full of debris and need to be cleaned.
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 water is dripping behind your gutter it s probably because it was installed without any flashing over the back of the gutter.
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.
There doesn t seem to have water in the loft so there is no leak.
A gutter apron is a bent piece of flashing that tucks up under the shingles and over the gutter.
And it doesn t stop there.
Damage to the roof and fascia.
Unfortunately it doesn t always work that way.
If the gutter is clogged some of that water will back up on the roof soaking it.
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.
The fascia itself is upvc not wood thank god.
When water drips between the fascia and the gutters the problem could be a compromised drip edge but it s also possible the gutters are overflowing.
It s a bungalow so quite easy to access.