# Unnecessary spaces generated during Subsurf

so my problem is that I've created a model that has a parametric form, so when I use subsurf to smoothen out the edges, these sort of faces are generated that interfere with even my freestyle outlining. How do I solve this problem?

• Are there any topological oddities going on there? Internal faces or otherwise non-manifold stuff? (You can select non-manifold geometry with Ctrl+Shift+Alt+M). If not, is it possible you could upload your .blend? – gandalf3 Mar 7 '18 at 5:14
• I used the default cube, merged it to a vertice, and then traced out a form, created a face and extruded a form. Then I used subsurf to smoothen the faces. Attached is the blend file. <img src="https://blend-exchange.giantcowfilms.com/embedImage.png?bid=4623" /> – Zahrin D'Silva Mar 7 '18 at 5:29