Works the same with a glass carboy!
As for heating - I have never even considered a heater for my brewing and we get temps down to -30! The basement cools off to the high 50's in January but it's not too hard to keep a carboy warm enough! If it does become a problem I find yeast that work better cold.
Grinders Island Brewery - Pipeline
Bottled! Award winning East India Porter, Oatmeal Stout, Milk Stout, Saison fermenting at a nice controlled 85 degrees (up from 70) as it should be - weird isn't it.