Housing chickens and ducks together?
My chickens would divorce me!
Seriously- I have chickens, ducks and a goose. I house the waterfowl separately from the ground birds. Their needs are so different that it would be interesting (?) to keep them together. Ducks are a blooming disaster- they turn the run to mud, they muck up the waterers, they spill food everywhere, the boys are too amorous/aggressive, they sleep on the floor under the chicken roosts, so they get pooped all over... I could go on. My chickens watch my ducks and goose from afar, and basically refuse to have anything to do with them. The waterfowl
want to join their flock, but the chickens won't have it. I have found that if you want to keep waterfowl and chickens- GREAT!! They are all wonderful creatures. Ducks are an absolute hoot! But, keep them separately housed and penned. Your birds will thank you for it.
Ducks are really low maintenance. I have a small, secure, low-slung house that they completely ignore until dark. No roosts, no feed or water inside, and no nesting boxes because they have never used one in their lives. (I have tried to get them to use some sort of nesting box for years and it still hasn't happened.) They have a fenced in run that they fly out of every day, including the goose. They spend the whole day foraging through the yard until dark and then they fly back over the fence and put themselves to bed in the house. They do what they want and I have resigned myself to letting them. They are great for slug and bug control. Geese are great for weed control. I feed them very little because they don't eat feed for the most part. And they are the funniest creatures known to mankind. I honestly keep them strictly for their comedic relief.
If you want ducks then you should get them because they are great. Don't put them in with your chickens, though. They require so little that it is easy to accomodate them.
Good luck.