The corner cut should be facing upwards.
How to install flashing on a porch roof.
Begin by removing the shingles at the affected area and removing old flashing if present.
How to install porch roof flashing step 1.
The metal flashing must overlap the material not the other way around.
Prepare the area where you will install the roof flashing.
The flashing on the wall should be flush against it and the porch roof portion should be on top of the shingles.
Nail the flashing securely in place using roofing nails.
Then nail the new l shaped flashing under the builder s felt but above the fascia board.
Apply a thin bead of silicone around the opening of the vent pipe area and lay the membrane in place.
Cut some membrane material to seal between the vent flashing and the roof and cut an opening for the vent.
Try to keep the nails as flush as possible to the edges.
Lay the cut flashing down at the corner over a shingle that is already in place.
Place the flashing between the joint of the house and the roof.
Use roofing nails to install the l shaped flashing flush with the roof and wall then cover it with roofing cement and reattach the roofer s felt.
Next place your vent flashing on top of the membrane.