Was just double checking to be sure the Pekins weren't ducks, have had chickens that were absolutely scared to death of ducks. How are the Pekins treating the Polish, do they bully or push them around in any way?
If they seem to be getting along OK, can you lock them in that part of the coop for a day or two, or at least until later in the morning, when they should have laid eggs to get them used to it?.. or divide it so the Pekins still have a place to lay eggs and only lock up the polish? If not, maybe try and put the polish in the upper part of the coop a couple of times a day just to get them used to it. Do you feed them upstairs so they have to go up there to eat? What kind of a ramp or ladder are you talking about, can you make that easier for them to use before a adding a new addition?
Polish for some reason seem to be lot harder than most chickens to talk into doing something new, if they aren't happy with what you have, building them something they like is probably easiest, but they do get used to new things eventually, they just tend to be slow about it.
