>>I am in St Pete FL. I provide heat when it gets below 60. I bought a few igloo dog houses, and I hang a ceramic heat emitter inside and that does the trick. Sometimes I use a timer to turn it off during the day, sometimes I just unplug it once the sun comes out. Mine are all at least 10-12 inches. When I had a smaller guy, I brought him inside when it got below 70. Good luck!
That sounds about like what we've done. The fist year we had our girl by the time it started getting down below 70 at night she only weighed 14lbs & below 70 was too cool for her. Now this is her 4th winter with us & she's about 55lbs, temps in the 60s don't seem to phase her but below that she's inside her home in the heat, she does that on her own now that it's chilly every night.
Last month when it was warm one night cool the next, then warm.... we had problems getting her to go home but once it got really cold one night, she's been going home on her own ever since.
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PHRatz