The rear of the third bay on our garage meets up with the rest of the house near our laundry room window on the first floor. The second story seems to create a river whenever it rains heavily. The bay is about 10 feet wide, and the little bit of gutter on the backside doesn't seem to be able to catch the runoff from the roof. It flows into the window and leaks inside.
We replaced Masonite with Hardie-Plank five years ago. The wall between the laundry room window and the back of the garage was rotted through and needed to be replaced with new sheathing. The contractor assured us that the water damage was due to the poor condition of the Masonite. But I think a new hole is developing in the same place even with the Hardie-Plank. It's not the siding.
After the siding was on, the roof started leaking into the garage. Brand new roof, and still leaking. So, they returned, and we paid them to install flashing on ANOTHER spot over the main part of the garage. Water was leaking into the garage...they didn't install adequate flashing along the roofline where it met the main house! They said that the siding was installed too close to the roof and they couldn't work under it without tearing it out. Duh!
We asked the roofers to address the problem by the laundry room window, but they told us it wasn't a roofing problem. They advised making sure the window was flashed properly.
So, we hired another company to flash the window properly. Still leaks!
When I look out the laundry room window during a rain storm, I see water pouring off the roof and splashing out of the gutter on the back of the garage. The trim under the gutter is rotting near the house.
Our neighbor is rather handy, and he has the same issue with the leaking window (our houses are the same model). His solution? Replace the window. Which I think we'll have to do, but I want to prevent this from happening in the first place.
Would it be as simple as adding a diverter to the roof above the gutter? We have one on the front of the house to help direct rain into a downspout. Don't know the rules.
Before I hire ANOTHER person to try to repair this problem, what should I be looking for and what should I know? I've been burned twice.