Why Is My Porch Roof Leaking In The Front

How do you stop the aluminum roof on the screened porch from leaking.
Why is my porch roof leaking in the front. Reasons for a roof leak on an external overhang. The porch has a roof over it with a decent overhang but the floor system is regular wood. The aluminum roof on my screened porch is leaking how do you repair. Do you go to a roofing contractor or a screen room contractor.
A roof leak is always a cause for concern. During the winter months blowing snow sits on top of the porch then on slightly warmer days it melts and leaks into the basement. My house is about ten years old. Identifying the cause.
We are having trouble finding where the leak is coming from on the outside. If the leak is dripping down just right in front of the house then there is a problem with the flashing connecting the roof to the exterior walls of the house. The contractor installed a waterproof layer over the plywood then ceramic tile filled with urethane grout. This flashing has two sides one connected just on top of the porch roof and the other to the exterior wall.
My house is about 10 years old. Step 1 determine the location and cause of the leak. I ve got water leaking and infiltrating the underside of my front porch. The water damage from a roof leak can extend well past the location of the leak.
It is like a waterfall on the porch with water coming down from all the seams. The porch has a roof over it with a decent overhang but the floor system is regular wood joists covered with plywood. One room leaks when it rains under the door almost where the porch meets the house. The water leaking down saturates the wood between the tongue and groove.