So you have decided to turn your garage into your workout area. Have you really thought about the cement garage flooring and how it might affect your joints? Do yourself a favor and pad the floor with rubber mats or workout flooring before you start working out. You can buy workout flooring sections at Home Depot. They make them for areas that people stand long hours on the job. Those same mats work out fine as cushions for workout areas.
If you decide not to have some sort of flooring over the cement floor you will be suffering from knee or back pain in about 2 weeks after you start working out in your garage.