There are many variables to consider in making this type of conversion. What is the roof deck / structural steel height above the floor? This can determine if you could accommodate a walk-on tension grid, or if you are limited to a basic pipe-grid. How much weight will the roof deck structure safely support? This can limit the amount and type of lighting, rigging, and drapes you can have. Only a Structural Engineer can answer that question with the input from a Theatre Consultant to inform them of the probable loads.
Is the HVAC system quiet? (Really quiet!?) If not, plan on having the HVAC design Engineer involve an Acoustical Consultant to get the noise under control (standard procedure for HVAC designers is to ignore noise issues until they are a problem, which is when it is too late to fix them). If the existing classroom ceiling is to be removed then the ducting system will probably have to be re-done anyway, this is an opportunity to get it right. If the room is basically rectangular with hard walls, then involve an Acoustical Consultant to get the room acoustics appropriate for speech.
Depending upon the capacity of the room, and whether or not you are planning an audience, the room may require additional exits and the installation of EXIT signs - this requires the involvement of an Architect to review the building code classification of the space. This may also affect fire protection, smoke control, and fire detection / alarm systems for the space.
The electrical and illumination needs of a Black Box Theatre are significantly different than a classroom, too, so the involvement of a Theatre Consultant to lay this system out is highly recommended (Hint: Don't let your Architect take the route of having their Electrical Engineer do it - 99% of Electrical Engineers have no clue how to design a theatre lighting system, let alone integrate it with the day-to-day classroom illumination needs). Also, avoid getting 'free' design assistance from local vendors - they have a vested interest in what they tell/sell you and generally don't provide an objective response. If they write the spec or install the system, who is going to check that it was done right - is the fox going to watch the hen house?
Flooring may also be an issue, as most classrooms are VCT or carpet over concrete - this is not very body friendly for actors, acrobats, and dancers. Development of a sprung floor design may be difficult and not suitable for a classroom retrofit, but you have to at least attempt to accommodate this need if at all possible.
Other accoutrements to consider are Dressing Rooms, Make-Up rooms, Storage Space, Shop Space, more Storage Space, and of course, more Storage Space (Remember: Will Shakespeare wrote "All the world is a stage . . ." - that's why there is never enough storage space!).
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Erich Friend
Theatre Consultant
Teqniqal Systems
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