I was given 2 chickens (12 weeks old) a few months ago. I was pressed to build a coop asap. I thought I was very clever and purchased a large wooden dog house. The measurements are 28in H, 40in. W, 26 1/2 in D. I replaced part of the floor with wire mesh, made the opening into a door, put in 2 perches 12 inches apart. I then pulled off the side and built 2 nest boxes: both 12 X 12 and 7 inches off the floor of the coop. I put the whole thing on cinder blocks so it was off the floor. I was really proud of myself! I then built an inclosure 8 X 6 X 6 and the coop is inside of it. Then we received 3 BR chicks that are now 7 weeks old. The 3 chicks go inside happily but they roost in the nest boxes. The older chickens keep roosting on the roof! (They always have, even before the chicks). What's up with this?? Every night I am out there picking up the older chickens (18 weeks) and putting them in the coop and trying to put the chicks on roosts (HA HA HA). Are my chickens really stupid or did I screw up? BTW, I live in Northern Ca so it is a mild climate... Please, any help would be REALLY appreciated.