Location: Atlanta, GA
Project: On the second floor of my house, there is an unfinished area just past the last room in the house and over the garage. So, the area extends from the 2nd floor and opens up to the attic...all the way to the roof. I plan to finish it off as a playroom for my kids.

Questions:
1. For the exterior walls, which are standard 2x4 framing, I plan on covering them with beadboard. I was told that, unless I'm using sheetrock or some other type of fire-blocking material, that I should use un-faced insulation. Given the fact that they are exterior walls though, I would think that faced is the way i would want to go. Any ideas?

2. For the exterior walls, given the climate, what insulation rating should I go with (R13, 19, 30)?

3. The room opens up to the roof. I purchased vent trays to allow air to travel from the soffets to the top of the roof. My next step is to put down insulation. I plan on covering it with some type of wood paneling (not sheet rock) so the same question for the walls comes up? Faced, un-faced?

4. For the roof, given the climate, what insulation rating shoudl I go with (R13, 19, 30)?

I don't have a lot of experience with this so I apologize if I haven't provided all of the details necessary to answer the question. I appreciate any advice/feedback. Thank you.

No matter what you use to insulate the exterior walls, the insulation should be covered with gypsum board, and especially so if you use beadboard, which will give off toxic fumes in a fire. If you use fiberglass, it should have a vapor retarder located on the winter warm side of the wall assembly.

If the exterior walls are framed with 2x4s, you're limited to R-11 or R-13 if you use fiberglass, unless you also install a layer of rigid foam insulation on the studs before installing the wallboard. Foams generally run about R-5 per inch of thickness. You should consult your local building code to be sure your insulation meets the minimums required.

Don't make the mistake of installing the vent trays all the way from soffit to roof. They will act as a partial second vapor retarder, and may result in your insulation becoming soaking wet, leading to reduced insulating values and possible mold and structural decay issues. Those trays are only to be used where the space between rafters and ceiling joists gets tight, to maintain the ventilation open at that point.

The roof insulation should also have a vapor retarder on the winter warm side of the roof assembly, and the roof insulation should have at least the value required by code. Again, depending on the depth of your rafters, the insulation values will be limited, especially when the required 2-inch (or 1 1/2 inch minimum) air space is deducted from the rafter depth. You may need to add wood to the bottom of the rafters to create greater depth, or you may need to install rigid foam over the rafters, in which case, you will be required to install wallboard before installing any wood panelling.

Foam board placed over the studs will not provide a solid backer to install your drywall. The foam will compress and allow the fasteners to break through the finished surface of the drywall if ever someone leans against the wall. Second, I would stay away from beadboard which is expanded polystyrene. You're better off using extruded polystyrene board. It has a better "R" rating and is more durable. You can get cardboard baffles to line your rafter cavities which will not create the second vapor retarder Richard speaks of.

Thank you both. Your replies were very helpful. Off to do some more research based on what you've enlightened me with.