I recently remodeled my unfinished garage, which created some attic space. However, the part of the attic is actually sealed with drywalls. I guess the contractor decided to block hard to reach attic space for now, but anyway that is the end result.

I just realized that there are no vents in that sealed area and I'm wondering if it is okay. I know the air trapped inside will get hotter during daytime, but so far under the July sunlight, it is not too bad (actually cooler than before without drywalls).

I also read about moisture issue during winter, but will it be an issue for a garage, which won't be heated? Any other potential issues?

Should I be concerned and install vents? Or other than the higher temperature, I should be okay?

BTW, I live in California (8-9 months of dry season then rainy winter) if the weather matters. Thank you.