Roof On Rental Property Leaking?

[ashly]

I had a new roof put on a year ago across the 4 car garage. My contractor I just hired to put siding on had a roofer that he knew put a patch on it for the ponding was. (it is still ponding) This roof was under warranty with my own roofer & the contractor jacked up the roof in the corner on the inside of the garage. It is now leaking in two area when it rains, but not where he jacked the roof up at. The leak is way to the far right & the center of the garage. My roof guy will not honor the warranty now because of another roofer doing work on it and the contractor jacking up the roof. The roofer that did the patch job said he did not cut into the roof & the contractor jacking up the roof has nothing to do with the leak and that my roofer I hired last year should still honor the warranty on the roof. Who is responsible for these two leaks? It was not leaking until the contractor jacked up the roof in the corner & had his own roofer put a 5 x 5 raised patch on it for the ponding. What do you do?