Yes, hollow core doors have solid wood frames. This is very different from doors like light weight closet doors which are completely hollow. It is important to make a distinction between hollow core (solid wood frame) and completely hollow (no solid frame, such as light weight closet doors), which we do not recommend.If you live in an older home and have hollow core doors that are shorter than 6'8, you may need to move The DoorGym next to the door hinges because there will always be a solid frame there. This is necessary in cases where your carpenter sawed off the top or bottom of the frame - and did not take the time to rebuild it - in order to make it fit. You can usually tell by feeling and knocking on the top and bottom of the door in order to tell if there is a solid piece of wood there. See our Set Up Page for additional information.