Don't bother if your hens are adults. If not, try using one of those electrician's lamps with a cage around the light bulb. Adult hens, in a wooden coop with enough other hens will be warm enough even when it dips down to -20 degrees F, which has happened at our place for 2 winters running. Too much heat in a coop won't let them develop enough feathers and a local woman burned down her barn using a heat lamp for chicks. MY 70yo wooden barn is NOT replaceable and I never heated the stall I used to keep my chickens in. It takes about 6 months of feed to get the first egg out of your hen. NOT worth it. Feathers are the warmest coat an animal can have and hens will sit on their feet to keep them warm in the winter and huddle against each other. The have to have 24/7/365 fresh air, even super cold fresh air. I always leave the door for the ramp, north facing, open. I DO use plywood to stop winter winds from the North, West and South, and block the wind on the outside of the run to keep it warmer where the ramp is. I use a heated dog water bowl that melts the ice even on the coldest days. I run a cord from my tool shed to the coop.
Don't bother if your hens are adults. If not, try using one of those electrician's lamps with a cage around the light bulb. Adult hens, in a wooden coop with enough other hens will be warm enough even when it dips down to -20 degrees F, which has happened at our place for 2 winters running. Too much heat in a coop won't let them develop enough feathers and a local woman burned down her barn using a heat lamp for chicks. MY 70yo wooden barn is NOT replaceable and I never heated the stall I used to keep my chickens in. It takes about 6 months of feed to get the first egg out of your hen. NOT worth it. Feathers are the warmest coat an animal can have and hens will sit on their feet to keep them warm in the winter and huddle against each other. The have to have 24/7/365 fresh air, even super cold fresh air. I always leave the door for the ramp, north facing, open. I DO use plywood to stop winter winds from the North, West and South, and block the wind on the outside of the run to keep it warmer where the ramp is. I use a heated dog water bowl that melts the ice even on the coldest days. I run a cord from my tool shed to the coop.