Thanks for your suggestions: Jejvtr, That's an interesting idea, making a mock-up of the door! I'm not concerned about any noise but--ahem, "bowl noise." Our pipes are cast iron and quiet, and our Toto toilets flush quite quickly (~20 seconds). Our bathroom is on the second floor and it would be quite difficult to climb in and out of the window (although possible). What I have been doing is leaving a radio on in the bathroom and seeing if different things lessened the noise. I know that's not perfect but it's all I can do right now. The door LOOKS tight in the frame, but we got some seal (weatherstripping) that I will put around the door tomorrow. I'm really trying to mock up the fire door, which of course has weatherstripping. I may look into acoustical tile and work on that mock-up idea... kitch n kat, I finally got around to the idea to hook the fan to the light (Dh can do that; he's really good at wiring, etc.) HOWEVER I tried the fan today and IT'S TOO QUIET! He sure as heck is not going to trade in a quiet fan for a noisy one (LOL) Nice that you thought of that idea first... I really like the idea of "extending" the door. We actually did that with our front door when the door company cut it off too short! I was heartbroken since it was a beautiful knotty alder door and I complained to everyone I saw. Fortunately I complained to our dear cabinetmaker who told me it could be fixed...and it was, beautifully. You can't even tell. We do leave the bathroom door open except when we have company (it looks a little tacky in our nice entry). Getting a different door is probably the best solution but almost impossible since the style wouldn't match. There's only the $900 fire door... I'll keep you posted if I make any progress. - Magpie

It is possible to design a solid paneled door to be effectively equal to to a flush solid-core door since most of the sound travels under the bottom anyway. A carved 1 3/4" MDF paneled door can have as much as 3/4" thickness to the flat panels. Unless you use edge and bottom seals no door is very sound proof.

Office noises are not difficult to contain with the exception of ink jet printers (use a laser printer) and phones (get a lower frequency ringer or light) but you are right, it is the doors that are the biggest problem. Gaskets around the perimeter of the door and either an "automatic drop seal" hidden in a slot in the bottom of the door or a gasketed threshold will do a lot. If the glass is single pane, double pane would be much better but expensive. A large sheet of tempered glass or plexiglass could be installed on the insides of the doors like a storm panel. A second set of single or double pane french doors (or solid core doors) could be added and gasketed on the other side of the door frame if there is room for the door swings. Once the doors are better you might consider vibration and high frequency sound absorbing materials in the room like dense foam pads under printers or even rigid fiberglass insulation wrapped or covered with fabric on the walls. If the carpet is thick that might not be necesary. However, thick carpets are usually a problem for rolling office chairs. Or put him in the basement like my wife did to me.

"Sound proofing" is not a realistic goal but reducing sound transfer between rooms relies on 4 principles: 1) mass 2) resiliency 3) absorption 4) crack & joint sealing Mass is achieved with masonry or thicker than normal drywall. Using a thickness on one side that is different from the other side also helps. Resilient materials and devices dissipate sound energy. You can use common or proprietary resilient metal channels to support drywall, drywall containing a resilient layer or gobs of green glue between 2 layers of drywall. In a floor, a thin resilient sheet will reduce impact noise. Absorption involves putting insulation in the cavity through which sound must travel from a crack on one side to a crack on the other side. It works when the sound must travel the long cavity dimension through a lot of insulation but it doesn't work as well in the short dimension unless the thickness is a foot or more so fiberglass is as effective as any other kind of insulation although some contractors will disagree. Crack & Joint sealing involves caulking the perimeter of wall plates and the edges of drywall panels as well as any penetrations. To achieve serious sound reduction in walls, studs and drywall should continue up to parallel joists, blocking between joists or to the floor deck above. Reducing sound transfer through a wall with a door in it requires a carefully installed acoustic seal on a solid core door with a drop seal at the floor which is generally impractical so the above principles aren't effective.