18 mth French Mastiff

Question
With me returning back to work. Is it okay to leave our 18mth puppy (french
mastiff) out in the cold for i.e., 20 degrees? He is house broken but we've
never left him for more than 10 hours and I'm afraid its not okay to leave him
for 12 hours by himself or is it okay?


Answer
Inside or out, 12 hours are a long time to leave any dog.  Inside I would almost count on occasional accidents.  Outside, he would suffer from the cold at first even with a tight dog house out of the wind.  He would develop a coat that would protect him.  

I would look into alternatives.  Could you leave him in the house and find a neighbor or a professional dog walker to give him a mid day break?  Have you looked at doggy day care.  I think it is one of the best solutions for most families.  You drop the dog off where it spends the day with other dogs with careful supervision.  He will be warm, have water, a great quality of life, and be safe.  All sorts of things can happen to even a larger dog left alone in a fence.  They can also make a nuisance of themselves by barking.