Subdivision Surface Problem! Help!

Hello all! Recently I was designing a human character model in blender. I was getting close to completing the model when I decided to add a subdivision surface modifier to smooth the model out. But when I added it, it created holes in certain places in my model! I’ve attached some pictures of before the modifier was added and then after it was added. Any help would be greatly appreciated! The blender file is attached.

Female Model 1, Unfinished 3.blend (598 KB)

Go and look at the places on your mesh that show errors and check your mesh. You haven’t shown any other settings (modifiers etc) so can only assume you are in control of those and know exactly what impact they may have on the mesh, otherwise you would have shown them. Since you have also decided not to attach a blend file we cannot check these for you

Remove any faces inside your mesh
Remove any double vertices (W / remove doubles)
Recalculate normals (Ctrl+N)

Thank you so much for your response. I’m new to the forum and the field of blender so I apologize for not adding enough information. Here is the blender file: Female Model 1, Unfinished 3.blend (598 KB)

Hi Sonlightcity,

The problems with your mesh were everything that Richard Marklew said. If you do the checks that he mentioned then you’re mesh will be fine. To toggle Wire Frame mode on/off use the Z-key. This will allow you to see inside your mesh to get at the interior faces.

It is easier sometimes to just select outer faces in solid mode and hide them (H, Alt-H reveals them again).
What’s marked red is causing bad shading you see; some faces are seen as edges only - these will be taken care of using ‘Remove Doubles’.

Thanks so much guys! I got the problem fixed! I appreciate all the help!