Attic Ventilation Question

[Jaime]

Hi Neighbors- 

Has anyone had to increase their attic ventilation?

We're in the process of replacing our roof and gutters. We have a gable roof with overhanging eaves, exposed rafters, decorative clay tiles on the roof ridge, and no soffits. Currently, the ventilation consists of one gable vent and two powered roof vents (the other gable vent was sealed when an addition was built on the side). 

Our roofers recommend upgrading the ventilation to rooftop intake vents and ridge vents for exhaust, but that doesn't seem common in our neighborhood. Curious what others have done to address attic ventilation.

Thanks!