I added another 1 1/2 car garage
Jim -
Here is what I started with:
I guess the best I can do is give you a link to facebook where I have an album of the whole process.
http://www.facebook.com/album.php?page=3&aid=48701&id=534316432
The existing garage was pretty short and narrow. My Ranger fits in it comfortably, but my Town Car can only be parked in it if you climb out the window.
I wanted to add on enough garage for another big vehicle, a ramp down from the house level to the garage floor level and room for work bench, riding lawn mower, tools, etc. So I added on 25 feet of width (13 feet from the existing driveway to the added driveway) and 12 feet of garage, by 49 feet deep (34 feet depth of the house and an additional 15 feet for a covered patio in back.
I tore off the existing gable over the single garage and replaced it with a larger gable over both garages. The rear has a matching gable over the patio.
The materials were $12,518.00 plus $3,200.00 for the 25x49 foot concrete slab, footed and poured. This also included an additional 85 bags of insulation to blow in to the original house / garage. The inside is mostly sheet rocked (including the ceiling) with peg boards for tool hanging. And an 18 foot long ramp down from the house (inside the garage).
I designed the addition myself. The original 100A breaker panel for the house was in the garage on the outside wall, next to the garage door. I replaced it with a 200A panel in the addition, moved all the wiring over to the new panel plus all the power in the addition. Got some friends to help put up the rafters - the rest was pretty easy.
If you have more questions or want more detail, just e-mail me.