My 4 1/2 week old chickens are in their completed coop -- yay! Only problem so far is the ladder from the coop to the run. (It's a playhouse-style coop/run.) My husband made the rungs for adult-sized chicken feet. Which isn't a problem getting down to the run, but they can't back up into the coop. The pressure-treated wood is too slick and they slide. Any ideas? Would sandpapering work? My husband's gone all week and I'm not handy enough to build another one. Thanks in advance.