Electrical wires in a home or finished garage are shielded from damage by permanent wallcoverings such as drywall, plaster, or even wood, but this is not the case in an unfinished garage. The key to safe, code-compliant exposed wiring is to shield and support the wires using frame members. If there is no framework around which to wrap wire, then it should be covered by at least one layer of tape. The National Electrical Code requires that all exposed parts of household circuits be enclosed in metal boxes or other enclosures designed for this purpose. The code also requires that all openings in metal enclosures be filled with suitable metal screening to prevent animals and children from accessing live electricity. If you want to work on your car inside a garage but don't want to risk damaging your wiring, then it's best to either hire a professional garage door installer or do it yourself. Make sure that you hire a reputable company that uses certified electricians and that has good reviews from previous customers. You should also check with your utility company to see if they provide service in your area. Some companies may not offer service if the distance between their main office and your residence is more than five miles. However, most utilities will extend their reach into people's garages where they can connect up to an electrical meter for service delivery purposes.