Heat lamp and winter ventilation

[cloverdalehens]

It's finally getting chilly in Texas and I'm wondering about heat and winter ventiliation. I currently have a red heat lamp in the coop and it keeps the coop around 60 w/ night temps in the 40's but when i turn it off the coop only gets about 1-2 degrees above the outside temp. Are the hens able to sleep w/ this red light on all night? Is it bad for them to have 15-20 degree swings overnight if I don't keep the heat lamp on all the time? How cold is too cold for chickens?

I currently have two inch holes drilled all the way around the top of the coop. I feel like this might be too drafty during the winter. Their roost runs east to west inside the coop. Should I close off the vent holes on the north and south side or the east and west?

 

[momma of a chicken lover]

Up here in Minnesota, the rule tends to be 1) avoid moisture build up, chickens make a lot of moisture so make sure you have ventilation to avoid respiratory problems and frost bite. 2) provide windbreak, make it so they can be out of the wind. 3) access to water, water heaters or consistent rotation of unfrozen water to replace the frozen stuff. We tend to keep winter hardy chickens. Two of mine are choosing to sleep in the area of the coop that is heavily armed against predators yet open air (kennel fencing lined with 1/4" wire mesh in a wood framed enclosure) even though we have had hard frosts. There is some really good reading on here about ventilation - somewhere... Good luck!

 

[Ridgerunner]

Here is an excellent article on ventilation. I'll throw in a couple of her other articles because they are so good.

Pat’s Big Ol' Ventilation Page
https://www.backyardchickens.com/web/viewblog.php?id=1642-VENTILATION

Pat’s Cold Coop (winter design) page:
https://www.backyardchickens.com/web/viewblog.php?id=1642-winter-coop-temperatures

Pat’s Big Ol' Mud Page (fixing muddy runs):
https://www.backyardchickens.com/web/viewblog.php?id=1642-fix-a-muddy-run

I did a quick check on Richardson's record cold. The coldest I found was 10 degrees Fahrenheirt above zero. That is not cold for chickens if they have decent ventilation to get rid of the moisture.