We're going to be building a master suite on our house some day soon, likely in 2017.

There will be a garage underneath, with 3 1/2 bays (3 bays with doors on them, one bay for shop space until that glorious day when I get to build an outbuilding and have a Real Shop).

Kim and I went to a home expo show at the Dulles Expo Center and talked with a fellow whose company does only garage doors, so that I could get a bead on the physical constraints we're working with garage-door-wise.

The basement ceilings are 7' tall and we would like to have a flat living space upstairs, so that means in order to go taller in the garage we need to have a step down outside. We could handle 7-14" more (one or two US-standard 7" steps) down from the top of the sill (level with inside basement) which with an outside pavement height of 3" lower than the inside floor would result in a cut of 4-11". Any more than that could be a bit rough.

We definitely do want the garage to be taller though. Assuming we want a standard garage door height of 7 feet (they actually come in 3" increments), optimally the height inside would be 8' or more. They like to have a foot of overhead room to work with, although one can install low profile track and get by with only 6" of headroom (ceiling height > height of door). Less than 6" is special engineering, pain, and money.