Down to two hens, looking for timeline advice for getting chicks

[PatinOxford]

We are in Chester County, PA, where it is being a cold winter. We moved to our farm in December 2013 and inherited five hens an a rooster. We knew they were not in the first bloom of youth :/, and in the 13 months since then all but two hens have died of natural causes. We have a RIR and a Silver-Laced Wyandotte left. The RIR just started laying again last week. Both seem to be in spectacular health.

I am planning to get six day-old chicks to supplement the flock and need advice on the optimum time to get them to have them ready to go out when the weather warms, and to have them producing and being grownup and hardy when next fall rolls around.

I have a large barn with a tack room I can secure and keep well above freezing, in addition to setting up a brooder for them. Can I use a large plastic tub set on two inch foam insulation (against chill from the concrete floor), and bedded with pine shavings as a brooder?

There are two coops on the farm, next to each other. I was figuring on fencing the smaller one against the older hens and the barn cats as the transition space. At what age do I mix the two groups?

I keep our girls free range on the yard (2 acres, tightly fenced) during the day, cooped at night. How old do the young ones need to be before I start giving them free range time (supervised)?

Just a few questions from a newbie...

 

[WildWestChick]

Welcome to BYC!!!

Now let's get down to business, are you looking for replacements for fall 2015 or 2016?

If it's fall 2015, then your going to want to get chicks this spring so they will begin laying around fall time / early winter depending on the breed you choose.

Your brooder room and set up sounds great, and will work just fine. You said you want to get 6 hatchling (day old) chicks, correct? Where are you planning on getting them from, a local breeder, feed supply/farm store, or a hatchery? If you want to order chicks from a hatchery and have them sent by mail I'm not going to lie you are gonna have a harder time finding a place that will ship less than 15 chicks. Without costing you an arm and a leg lol. And most don't start shipping chicks til at least February.

Do you know what breeds you want?
Are you interested in just lots of eggs or pretty colored eggs, or even dual purpous chickens?

The coop sounds good, especially with the space that they can get to know each other through the fence. You don't really want to coop the adults up with babies until they are almost adults themselves or you could have lots of fighting. I'd say once they are close to the same size (again depending on breed) you should be good, which should be around 4 1/2 - 5ish months old. And they shouldn't be out in the coop exclusively until they are fully feathered and have no more baby fluff...again this depends on breed but usually around 5-7 weeks.

They can free range (supervised) from day 1 if it's not too cold outside (70*+). But only for short periods of time (10-15 mins max) until their feathers come in. Any longer and they will get too cold outside of their brooder.

I hope this helps!!!