I buy the plastic poster board from Walmart, make a long sleeve that is at least three to four inches longer than the bottom of the tote. Put the poster board in and fold the end under the base. That way I can wash the tote (with the sleeve pinned to the tote so they wash together and the sleeve does not join all the missing socks in the “hosezone”), as needed, and the plastic is not damaged. I did sew a piece of plastic canvas into the base of a purse I made, but when it was washed, the plastic canvas had crumbled from the heat of my home dryer. I had to remake the purse.....Grrr!