my puppy use to do do that too! its like they hold it until they get back in the house. my pup is older now, and she lives outback...so now i dont have to worry about it anymore... but have you tried the puppy pads? try giving her a treat whenever she does go outside so then she knows thats the right way. :)
How old is your pup? All dogs are different, two I adopted and they were already house broken. The other two. Well, lets just say when I got Ariel, a chi, a swore up and down that she would hold it until I let her back in no matter what. It took a while, longer than I would have thought, but she's fine now. If she has to go she goes to the backdoor and whines to go out. No problem. Also, are you crate training too? That can make a huge difference.
an hour is too long. crate train the dog. fisrt do not confuse crate training with pooty training. the crate should be just big enough for the dog . it' head should touch the front while it's bum touches the back. and the crate shouls not be an wide. why? cause dogs usually will pee or poo where they have to stay. then let your dog out every hour, for five minutes return to the dog to the crate if it does not go. and feed the dog in the crate and have it sleep in it. never use the crate discpline, this will help the dog learn the crate is fun. every time your dog poos or pees in the house this works against you. never give the dog that ooppurtunity during potty training. if the dog is ut of the crate in the house tie a leash to your waist and keep the dog close.