A little brain teaser for y’all on the subject of attics/roofs. Here are the givens. Read closely.
An 8 year old home.
Roof covering in good condition, except for a few nail pops.
All flashing in good condition and properly installed.
Drip edge with kickout installed properly on all rakes and eaves.
Attic construction is an engineered truss, no deflection worth mentioning, with no cut members.
Sheathing is exposure 1 plywood.
Heavy felt underlayment.
More than adequate ventilation with soffit and gable vents, plus turbine assist.
No exhaust fans from baths, etc vented into attic.
No moisture problem in attic.
The roof has never leaked.
Despite all this, the roof has “waves”, or humps and bumps.
What’s the problem? Have fun!!