[Trintcole]

I had to remove the attic fan from my roof because it was leaking. There were some rotted out section so I cut a square hole and sistered in some 2x4. I put in a new plywood roof panel. My question is, the new roof panel is 15/32 and I believe my existing roof is 19/32.

Will having the slightly thinner roof panel patch cause a leak?

The section that is patched is slightly lower than the rest of the roof.

I have to repair the drywall underneath, and it's a rental house so I'm not there to watch it, so I want to make sure it doesn't leak again.

The guy who help me do it says it should be fine.

 

[Windows on Wash]

Depending on how they put in the 2x4 bracing, it should be flat on the exterior. If the interior side is a bit lower, that is less of a problem than is the exterior side having a dip in it.

 

[Trintcole]

On the exterior, the square is lower than the rest of the roof. Maybe a 16th or 3/32

 

[craig11152]

I would (have) shimmed it up with shingle material, one layer of 3-tab or the top side of a laminated , cut to fit.

 

[joecaption]

A picture of how you did the repair would help.
If you removed whole shingles carefully, not just do odd ball length butt cuts, weaved the new shingles in, covered the patch with tar paper making sure to over lap the sides and bottom and slid the top part under the old tar paper it should not leak.
Hard to know if it's going to leak or not without seeing or knowing exactly how you did it.
I saw one repair that was done by a home owner in a hurry for a closing where there had been a weak spot in the roof where he had simply cut out a hole in the roof, used 1 X 4"s for backers, sheetrock screws to hold in place then just laid the new shingles over the old ones and used about 1 gal. of roofing tar to cover the whole thing.
Guess what, it leaked.

 

[Trintcole]

Ok . The current roof is 1/2 plywood. ,I used 15/32. Apparently 1/2 plywood is no longer made. House was built in the mid 80's.

I put new tar paper, weaved it under existing at the top and over existing at the bottom. Removed enough whole shingles to access work area. Weaved in new shingles for the repair. I cut no shingles. I'm confident the shingle and tar paper was done correctly.

Just wasn't sure if water could collect at the lower ridge of the patch.

Also sistered 2x4 on the sides and put in horizontal bracing at the top and bottom of the hole. Attached patch panel with outdoor decking screws.

Thanks for everyones help by the way.

 

[craig11152]

Ok . The current roof is 1/2 plywood. ,I used 15/32. Apparently 1/2 plywood is no longer made. House was built in the mid 80's.

15/32 and 1/2 are interchangeable for a roof. Now days they are essentially the same thing. In your original post I assumed you were talking 1/2 (15/32) and 5/8 (19/32). .

 

[joecaption]

Sounds like you did it right.