Concerns with Buckles in New Build Roof
Buckling shingles could be caused by 1) lack of ventilation in the attic, 2) improper installation of the roof sheathing, 3) improper nailing of the shingles, or 4) wrong type vapor barrier.

1) If the attic is extremely hot, the shingles will buckle, especially if they are not nailed correctly.

2) If the roof sheathing isn’t nailed correctly or doesn’t have the correct spacing (gaps) between sheathing panels, they could expand and cause buckling, which would “telegraph “ through to the roof shingles. 

3) if not enough nails are used or if the nails are in the wrong location, the shingles could buckle. 

4) if a “rag” type vapor barrier was used, it could buckle if it got wet.