I have 5, five week old chicks (or are they pullets?) and I just put them outside today. Highs will be in the 90's and lows around 60f. I have a heat lamp in the hen house keeping it around 75ish in the periphery. There are two 10"X10" open metal clothed windows near the top of the henhouse to allow for air flow. Should they be alright? They have all of their adult feathers already and with the heat lamp in the henhouse I thought they would be ok. Run is almost done should have the whole thing finished by Sunday and I will post pictures. I am new to this site and new to chicken keeping so any help would be great. I guess I should also mention our small flock consists of an Anmericauna, Barred Rock, SL Wyndotte, Houdan and a White Crested Polish. I live in the Pacific NW and this is a brand new venture for our family. Thanks!