In cold weather environments, it's all about getting plenty of good insulation into the roof, which is where the majority of heat escapes a structure. That's why you're well served by having wide ceiling joists. See what that means right there.
When it comes to plumbing, there's nothing pretty about it. And never is it uglier than when you're running a main sewer line through the yard. Here's a glimpse of this nasty project in its full glory.