If you've chosen this as your pup's lifestyle - and it's certainly your right to do so - then you should perhaps also think about choosing a breed of dog that will adapt reasonably well to that type of lifestyle. IMHO Goldens are unsuited to this type of arrangement.
Goldens are people dogs. They do best when they live with, and in the same space as, their people. The many Goldens I've known in my life would have been sad at best and miserable at worst if kept outside alone for long periods. Take my current Golden, for example. We have a back yard to die for: 40,000 square feet, fully fenced, half of which is woodland with squirrels and birds to chase. You would think there's lots to keep a dog occupied. Well, when I send my Golden outside, he runs to do his business, then runs straight back to the door and asks to be let inside. He just wants to be with us. If I go outside with him, he's happy to play and explore. But not on his own. My last Golden was the same. They are a breed that just prefers to live indoors with their people. We have another dog of a different breed, and he will spend longer periods outside alone (up to 10 minutes sometimes, before he asks to come back inside). But not the Golden.
Since you're set on keeping the dog outside, I would suggest a more independent breed, one that will adapt more easily to the outdoor lifestyle you wish to offer it. I urge you to think carefully about this. There are breeds that adapt to this. Goldens aren't one of them.
My brother lives in Europe and is a sheep farmer. He has several working border collies. He keeps them in a barn, in kennels that are cleaned several times a day. The dogs are warm and well-fed. However, they also spend several hours a day, every day, working with the sheep. They're taken for long walks every day, off-leash so they can run, and they're trained regularly. They ride on tractors. They compete in sheep-herding trials. They're living the life they were bred for, and they're happy. He also has a Cocker spaniel, and this dog lives in the house. It goes for rides in the car with my brother, and sleeps on a rug in the kitchen. It would be miserable outside with the other dogs. It's a pet. It doesn't work and it wasn't bred to live outside.
I respect the fact that you've "sorted this out", but there are a few things that you may not have thought of, regardless of the breed of dog you get.
The first is barking. A dog left outside alone is going to bark. It's what they do. Our neighbour, for example, has a Pyrenees mountain dog that used to live outside during the day. This is a breed that adapts well to living outside - it's what they are made for. However, that dog barked at every noise, every car in the street, every time someone in the surrounding houses went outside. It was a real pain. People complained to the city. The dog is now kept in the house.
The second is the bad habits (other than barking) that the dog is going to develop, especially if you start out with a puppy. A bored Golden (and any dog who spends long periods outside alone is going to be bored) is going to dig holes, chew fences, eat stuff off the ground, etc. Then, when it sees its people, it's going to jump on them, bark at them, etc. It's what they do. Goldens are energetic, intelligent, exuberant dogs. It's important not to underestimate their need for mental stimulation, and their need to feel like they're part of the family.
The third is safety. My back yard is fully fenced and we live in a very safe neighbourhood, but I wouldn't dream of leaving my dog outside when I'm not at home. He may be stolen. The yard gate may be left open. He may get his leg stuck in the fence. He may chew a stick and choke. There are too many things that could go wrong: I just wouldn't feel comfortable, knowing he was out there, unsupervised.
To address your specific concern about the cold weather, your dog will develop a thicker coat during winter. The temperatures you describe aren't overly cold (I live in Canada, where it gets down to minus 20 or more in winter), so the thicker coat, combined with a well-insulated shelter, should do. However, the thicker coat also means more grooming, several times weekly, to avoid matting, and it means a lot more shedding. You will also need to keep your dog well-protected from parasites (fleas, etc.).
I wish you good luck, and hope things work out for you and your future dog.
Ruby 13-01-2007 to 18-03-2015.
My dog of a lifetime. I'll miss you forever.