chances are if it is in the garage you dont need to let it warm up for that long. the only time i would really need it is when i was up in the mountains to melt the ice on my windows in the morning, but other than that, if it were in a garage i wouldnt have that problem. sure it might be a little chilly inside, but as long as you are nice to the poor thing, it will heat up within a few minutes of driving. other than that, it was nice to have it when i was working outside on a sunken below ground level baseball field with no breeze and humidity like crazy because of the water in the ground, especially on 117 degree days this summerThat's scary...garage doors jam, power fails, they get left open or part-way
open. Some things just need to be VISUALLY verified to be safe.