I used 2x6 studs w/ top and bottom plate. Mark along the beam where the studs will be, then measure from beam to floor, subtract 3 1/4" for plates and wiggle room. Frame up your wall section, nail some 16d's about 1/2way in to both sides of top plate every 2' or so. tilt up straight and slide under the beam. Plumb you wall pretty close, and then shim each end to keep it in place. Then shim above (but off to the side a little), every nail nice and snug, then bend the nails over the edge of the beam. You can then screw in some metal screws through the top plate if you wish, but that wall wall ain't going nowhere. A little trick I picked up nailing bottom plates in concrete is to predrill a hole through the plate and in the concrete, the whole depth of a standard bit. Using a galv. 10d box nail and a bare piece of 12g wire, with the wire being 1/2" shorter than the nail, or depth of the hole. Drop the wire into the hole, then hammer the nail as far into the plate as you can. I have tried to pull up a bottom plate that I put in this way, and the 2x6 got shredded, leaving the nails in the concrete. You really only nead lateral strength at the bottom plate anyway. I cannot remember the size of the drill bit I used. Put the nail and wire together and compare with bits, and use a slightly smaller bit to get that snug fit. This is a lot cheaper than tapcons, you don't mess with the beam's integrity at all, and is farily simple and fast. I hope you were able to follow along. If you have any questions, I'll try to answer them for you.

Steel is expensive, and right now lumber is really cheap. You might want to look into engineered wood beams. They have the benefit of large spans without the hassle and expense of steel. We decided to save $$$ by going with larger wood ceiling joists and got less than what I wanted. The 2nd floor over that area flexed so we asked the framer to put in some bracing to minimize the flex. It worked ok, but in the next house I build I will find the extra money to put in the engineered wood beams. With the engineered wood beams everything works just like it would if you used regular dimensional lumber. One thing you need to consider when looking at steel is the fact that it will restrict the location and routing of your electrial, plumbing and HVAC systems. Its not a good idea to cut through the web of a steel beam or a wood beam, but a wood beam is more forgiving. Stresses set up in the steel beam and multiple flexing over time can result in stress fractures and possible failure. Plus the steel is just hard enough to deal with where your contractor will ding you a little in the wallet for having to mess with them.

I live somewhere that ceiling fans are seldom used so I don't know if this would work..but I put a Fantech bathroom fan in my new bath that would suck the fuzz off a peach. It is a very strong motor hidden in the attic space (so it is virtually silent) and it has two fan outlets connected by ductwork, one in the shower and one over the tub. It is a very small grill around a halogen can light (small, maybe 2"? light). It is not noticeable as a fan and if I turn it on, I can feel air being sucked under the bathroom door, a LOT of air. I don't know if air circulation by sucking instead of blowing would work for your purposes, but it would definitely move the hot air off the ceiling. The light and fan operate independently. This is my model and I see they have an add-on so you can have 3 outlets. I chose the halogen because it could be dimmed and was a smaller bulb I think. The premium is rated for a higher cfm. Maybe you could talk to the company and see if they have experience with this kind of application. It is SOOO quiet! Here is a link that might be useful: Fantech

Thanks everyone - this makes sense, and I like it. Plus my husband LOVES to apply auto body paint, he would paint the entire house in it, I think, if I let him. Thanks!