I covered the bottom and 2/3 of the way up with plastic sheeting. I found a heating pad that doesn't have auto shutoff. I tied it to the underside of a cookie cooling rack and covered with a towel. I've got the MHP running with a thermometer in there to see if it gets warm enough while the chicks are in the other brooder under the heat lamp. Can anyone tell me at what age they won't need this anymore? They are 10 days old now. The temps are in the 30s at night and 50s-60s during the day. That will probably drop about 10-20 degrees over the next month or so. The garage has been in about the 50s at night, which is where they are now, but I would like to put then in the coop when it is safe and healthy for them. I just don't know when that is.