It must be allowed, that's what the drain lines are made of (at least here in Canada). No issues with fire. Also, I'll be running the conduit along boxed ducts at the ceiling where there is plenty of interstitial space. Vertical lines will come in my furnace room and a closet where walls will be unfinished. Also, my perimeter walls are 2.5" metal studs and the partition walls are 3.5"- nice and solid and plenty of room to run conduit. I figure, the larger the diameter, the easier it is to fish new cables.
Yes, we'll just close the basement door. Kid's rooms are on the second floor two flights up, so it shouldn't be a problem. I'm not too worried about sound insulation in the basement. If it was on the main floor, then yes, I would definately do it.
Planning is key. I used a technical drawing program to draw out the layout. I prefer metal studs at they are lighter, easier to work with (just need metal snips), provide perfectly straight walls and are resistant to mold, mildew, termites and fire. Use wood studs for door framing however (that's where metal studs don't really cut it). If you plan to frame yourself and don't have a whole lot of experience, then you really need to imagine how the frames will take form. Walls must be square to each other and studs must be plumb. Framing is very important because its the foundation for how your walls will look in the end. Personally, I hired a professional- got a good price and his workmanship is top-notch.
