Winter housing in Houston

[Lady Lavender]

We recently purchased a home that has a new barn on the property, I was considering using it as a place to keep my birds in the winter (not that we get much of a winter) It has skylights and windows and is made of metal. The area I would use is 20'x40'.
My question is, if I use the barn, is it safe to use a heater to keep it warm at night? I have never used one before, this would be an electric not kerosene heater. One of those tall standing ones you see at restaurants. The building is metal so I'm not concerned about a fire, I'm worried about toxins or over heating. Does anyone have one of these that they can advise me on it? We dont have central heating in our home only air conditioning and last year when we brought the birds in the house, I actually turned on the oven for them because it was only fifty degrees in the house. That is rare for us but it when it happens I worry about them. I usually use infrared heat above their cages when the temp starts falling below 70 at night.

[Lquan]

Parrots will do just fine around 30F. They can tollerate cold weather better than finches. If your finches are kept outside to acclimate since spring/summer, they will do just fine in the 30s during winter night. I live in Southern California where it can get to high 20s at night in the winter. My friend lives a few blocks away who has a large outdoor aviary with some 50 finches. He puts up bamboo shades and canvas tarps around the aviary during the winter to keep the wind and rain away. He never uses heater or heated perch. And he never lost a healthy bird due to cold weather. He has Gouldians, Stars, Green Singer, and even Owls that are known to do poorly in the cold. If any finch looks weak or sick, he keeps them warm in his garage for treatment.