We are currently in the process of finishing a playroom for our children in our basement and are trying to finalize our flooring plan. Originally we had planned on laying laminate flooring, but have since determined that the floor is not level enough to do so. Now we plan on laying vinyl flooring that is made as planks and look just like wood (sold at Menards). However, we are afraid that the floor is going to be too cold for little ones. Any suggestions on inexpensive underlayment options to increase the comfort of such a floor? Someone recommended plywood but I am not sure how I would fasten this onto the cement. Thanks in advance!