Practical advice about a car battery 12VDC to 110VAC inverter typical length of time to last without electricity

[Clare Snyder]

Garage ventilation is USUALLY to prevent them turning into ovens. Not too common much north of the Mason Dixon line - --

[Jim Joyce]

You could well be right, Clare, but I don't understand how that would work. The concept of hot air rising doesn't seem helpful here. That's why I guessed that the vents might be more related to CO safety, but that's probably also limited.

[rbowman]

CO is slightly less dense than air so vents in the bottom of the door wouldn't help, nor would roof vents.

[Clare Snyder]

The garabe with the vented doors usually also does not have a sealed ceiling and/or upper walls - and vents through the soffits and/or ridge vent so when the sun heats the roof you get a pretty powerful convection. Enoght that the "attic" is often filled with dried leaves etc seucked into the garage. The cool air comes in the bottom of the door, is heated, and exits the roof

[Jim Joyce]

Interesting. My Kansas house had the master bedroom above the garage and my Texas house had a 400 sq ft play room above the garage. Neither of those garages had any other venting except the dual vents down low in the garage door. There was no appreciable air movement in either case, and especially in Texas, the garage was a hot house during the summer.

[Clare Snyder]

So your garage door vents were pretty much useless.

[Jim Joyce]

Yep, now we're on the same page. My thought, exactly. :)