7 week old chicks in Coop. We live in Seattle--down to 40's at night. Do I need a light/heater?

[AriLovesChickens]

Hi - I'm in the Seattle area too.

My chicks (not bantams) are 9 weeks old, and I just cut them off the heat lamp last night. I had it inside the top of the coop, clamped onto a board, and they liked to sleep under it. I might have waited a bit longer than some to stop using it. The coop is somewhat open (the floor isn't all closed), so I was afraid of it being too drafty when I first put them in it a couple of weeks ago. I think they're fine now.

 

[LadyBs]

I have four chicks. They are 7-8 weeks old. We just put them outside for the first time today. The coldest it will drop tonight is 50 degrees, it was almost 90 today. They are locked up in their coop for the night, do they still need a heat lamp? Please any advice would be so great!