OK, I have a flock of 16 chickens (RIR, SLW, & EE) that are almost 9 months old. I lock them up tight in their coop every night for protections from predators & elements. My coop is about 8 x 10 and insulated. I'm using deep litter method. On super cold nights I give them scratch to help heat them up. I usually leave one window slightly cracked for ventilation, but I shut it tonight. There is small vent holes up high in the front of my coop above the main door. Today is super cold. The water froze in the run & in the coop earlier today. I don't have a water heater yet, but I'm looking for one that will work with my plastic waters, b/c I didn't want to have to switch to galvanized ones. It's about 20 degrees F outside, but it says it feels like 4 degrees. Inside coop is about 32-34 degrees F...just barely above freezing. The wind is blowing about 26 mph. On other cold nights the coop seem to hold at 38-40 degrees on the inside, but I guess it's the wind causing it to drop lower?????? Tonight I fed them some warm oatmill about 45 min before bedtime to help warm them up. I don't know if it was a good idea or not b/c all the EE got it all in their muffs on their face, then water was sticking to them when they were drinking. I had to dry their little faces so they wouldn't have popcycle muffs. I have not used heat yet, b/c I wanted them to acclimate to the weather. This is the coldest inside the coop it's ever been. They seem so miserable today. Hubby even felt sorry for them today and wrapped a tarp around 2 sides of their run to help block the wind. What is the coldest temp in the coop before you use a heat lamp? I have an infrared heat Lamp 125W, but hubby says he didn't think it would warm anything up in there. I also have a 250W infrared clear heat lamp. I know chickens are pretty resilent and they huddle together to keep warm, but just want to make sure they are warm enough. At what temp do you experienced chicken owners use a heat lamp? Suggestions are greatly appreciated. Thanks! Worried chicken mom.