If your budget permits I'd say you would do well to consult a professional acoustician or studio designer. You would definitely not want any 'pinging' that might occur from the room having a metal infrastructure but how much treatment you'd need to remove this would need proper and a specific examination of the room in question.

Given the fact that any such building is going to have a reasonable cost it would almost undoubtedly save you money to factor that into your plans and get the result you need first time rather than wing it and have to redo or, worse, not be able to use the space for your intended purpose.

Post again if you can't find appropriate professionals in your area but an online search will probably net a result.

Good luck.

Fantastic. Thanks. I will see what I can find close to my area, though I have doubts of any professional services such as these around here! I'll see what I can do. The initial walk through in the building didn't reveal any noticeable ehoes or anything that really stood out for "metallic" sounds, but that is just a general observation. The buildin's factory insulation is really quite dense so hopefully I will find that it will be ok once I have it analyzed. Thanks very much for the professional advice & opinion. -ck.

Download a copy of REW (Room EQ Wizard) from here: http://www.hometheatershack.com/roomeq/
The software is free. All you will need in addition to your normal listening setup is a decent mic.
This software will allow you to acoustically profile the room so you can determine where your resonance peaks and nulls are. With this information you can target problem frequencies for treatment as well as optimize your desk and monitor configuration.
It's quite easy to use and will immediately tell you if you have any acoustic issues.

Another more manual approach would be to set up a mic at the listening position and play a ramped tone while also recording it. Then view the recorded wavefile in a wave editor. Look for the valleys and peaks in the overall envelope of the recorded file - the editor should indicate what the frequencies are.

Ok, I'll check into that for sure. The building is just an empty space currently, will this EQ wizard be helpful for analyzing it in that condition? Also, what would I want to see for optimum frequency responses at the pre-interior build stage? It doesn't seem like it would really help a lot by testing before the interior is built, but I can see where it actually might be necessary in the case of a metal outer structure to make sure there aren't any serious issues. Thanks, -ck.

At the current stage of your studio space, i.e. an empty shell. The only test you'd really need to perform would be to play some test tones and maybe a recorded drum sequence or just music - at about 90 - 100dB then check with a dB soundlevel meter (radio shack has a popular one that is quite inexpensive) at points outside and in other rooms to get an idea of how much sound will be getting out - ergo, how much isolation you are going to need. I again recommend you drop into John Sayer's Forum - even if you don't register, you can peruse the postings and I guarantee you'll learn a lot about the triple leaf issue, double wall construction, inside out wall construction, etc.

Ok, thanks again for the input. I have registered on John Sayer's Froum and have done some fairly extensive browsing of the topics. I also own a dB sound level meter as you mentioned, so I think I will be in good shape to proceed with the initial pre-construction tests. Thanks to all with the assistance, it is very much appreciated.