more on the remodel front

So, remember when I shared with you about my son and his family in Chicago beginning a major remodel on the house they bought?  Well, things are moving right along (from this distance anyway...  I am sure it seems to them to be crawling).  So here is what the back of the house looked like in January...

and here it is now...

They just asked me for a suggestion for flooring in their mud room.

Hmmm, in Phoenix that's not really something we ever have to deal with...

So, any cold climate folks have a good suggestion for a Chicago mudroom floor?

Also, my daughter-in-law is obsessed with built-in bunk beds...

What are your thoughts?