Rectangles Render as Triangles?

My mesh is made of rectangles, but they are split diagonally into triangles when I render it.

Can someone help me have it render as rectangles again?

All faces are converted to triangles for rendering. If you have a non planar face and flat shading you will therefore see it as multiple triangles.

This look more than just that. Post a link to your blend file so others can check it out