Are DVD-RW discs thicker than DVD-R's?

[dbminter]

I was wondering if DVD-RW discs are thicker than DVD-R's.

 

 

The reason I ask is when I use my disc shredder to destroy DVD-RW, it does it slower and louder than it shreds DVD-R's.  That seems to indicate to me the shredder does more work on DVD-RW than DVD-R.  The only reason I can think of this might be the case is that DVD-RW's may be thicker than DVD-R.  It may not be perceptible to the human eye, but it could be the case?    Maybe a rewritable layer is thicker than a WORM dye layer?