This can be a real concern if the height of your new flooring is different than that of your old flooring. This is not something we can predict at the time of your measurement because we do not know what thickness the new floor you choose will be. If this occurs, the installer will bring this to your attention. Contact Lowe's for information on pricing to have doors cut down, if that is a service your location provides.
Not all of our installers are able to cut down doors because this is really a job for a trim carpenter, not a flooring installer. Lowe's will let you know if we are able to cut them or if you need to contact someone outside of Lowe's to do the job. We are never allowed to cut exterior, metal, bi-fold or hollow core doors. A quick Google search for "Carpenters near me" should help you find someone to do the job quickly.
Note: If your doors are removed before the installers arrive, they will not reinstall them. Our installers only attempt to reinstall that which they uninstall, if at all possible.