There are two reasons for water getting behind the gutter.
Install rain gutters drip edge.
Use tin snips to cut the gutter apron flashing roll in two 3 in.
Home centers sell rolls of 6 in.
Attach the outlet.
A gutter apron is installed on the corners above roof decking.
While on the other hand a drip edge is installed to the trim and usually hangs directly behind the back of the gutter.
It is put under the shingles of an attic to flow water directly into the gutter.
Attaching the downspout outlet and caps 1.
How to install a drip edge slip the wide flat flange of the material all the way under the first course of roof shingles as illustrated.
Make sure the outer edge extends over the gutter.
Choose green snips if you re cutting clockwise and red tin snips if.
Lay the gutter into the brackets that you ve lag screwed to the fascia.
Measure from the corner of your home to the center of the downspout.
Through the screw mounting hole in each bracket drill a 3 16 inch diameter hole in the front edge of the gutter.
Rotate the gutter upward until its back edge slips into the hooks at the top of the back of the brackets as shown.
Remove the outlet hole using offset tin snips.
A gutter apron is used where shingles are not far enough from the edge of the gutter.
Mark the location of the downspout outlet.
If there s a drip edge installed where the fascia meets your shingles and the gutter is hung below the drip edge get some roll flashing and tuck it up under the drip edge and over the top of the gutter.
If it doesn t pull the drip edge out slightly from under the shingles.