Quote Originally Posted by EvergladesExotics View Post
Correct, there’s no ceiling, just the roof. There is mesh venting on the underside of the soffits on the outside. Do you think these combined with two up-ducts would be enough to keep the smell from coming inside the main house? I’ll also be putting in a window a/c unit if that matters. Thanks!
You wouldn't use up-ducts, they go in the ceiling (that you don't have). (-sorry, didn't mean to confuse-)

I think a window a/c should be fine. Cool air sinks & warm air rises- you'll have to try it, I'm not sure if it will vent out the soffit vents well enough- you still might
need an exhaust fan for best circulation. Make sure the bottom of your garage door has a good rubber seal on it, otherwise you'll lose a lot of cool air under it, &
lots of wild creatures may also want to come in. (for cool air or the rodent perfume, lol) Also, make sure the door into the house has good weather-sealing
on it (to help keep out the garage air).