How does roofer know the thickness of the sheathing without
ripping-off the shingles? Seems to me that he'll need to use the
same thickness to match the existing sheathing that has not buckled.


1. By knowing local building practice is to build in
conformity with the llocal building code.
2. By knowing what thickness of roof sheathing is
specified in the local building coded.

Both appear normal for successful roofers.

Pretty good logic .. EXCEPT .. "CODE" does not specify what material or
thickness to use .. .. only the MINIMUM allowed. How would he know if
the structure was built to custom specs that exceeded the code ?? I
still say you need to determine what caused the buckling before you can
do much to correct it.