24 x 24 is the standard dimensions of a two car garage. Smallest being 20 x 20 and as much as 28 x 40.
I highly recommend that you measure the size of each car that will be housed in your garage, as car sizes do vary. Also, keep in mind the changes in vehicles during the time stayed at your current residence. You may have a compact car now, but what if you want a mid size car or truck later on? This, and a few other factors must be considered before making this costly investment to your home.
ONE SIZE DOES NOT FIT ALL
As mentioned previously, you may have a two car garage, but that doesn't mean any two cars can go hand in hand, or should I say wheel and wheel. Let me put it like this, don't design a garage based on average or random dimensions or you could find yourself with a two car garage that can only hold two smart cars. So again, measure your current cars and contemplate whether or not any future trucks with an extended lift kit will be taking over.
HOW SHOULD I BEGIN THIS PROCESS?
Make sure everything you're constructing is approved by your local authorities (jurisdiction) and permit applications are filled out and accepted. A building inspector can assist you in this process to ensure everything you're doing is legal.
HOW MUCH WILL THIS COST ME?
Two Car Garage Dimensions Prices will vary depending on the dimensions you choose and extra fixtures. Most families use their garages for multi-purposes, for instance, a laundry room, work shop, a place to change the oil of your car, and lawn mowers. This means you will need proper ventilation unless you don't mind leaving the garage door open while you work, but you may need to check with the rules and regulations if your residence has a HOA (home owner's association), because most don't like car maintenance being done in eye sight or to see people switching loads of laundry.
On average, if you're looking at a two car garage with 400 square footage which leaves just enough periphery space along the walls for door opening space, look into spending $30 - $50 per square foot $12,000 to $20,000. The more favorable, but costly option, is 800 - 850 square footage. This will run $29,000 - $38,000 including adequate space for lighting, ventilation, work shops, washer-dryer hook up, and attic storage.
Keep in mind, you will need to pay for garage building plans ($20-$200) and the cost for permits. These prices will vary depending on your design which a building inspector can assist you with.