TV production spaces
Nov 1, 2008 12:00 PM, By Antonio Argibay, AIA
The first article in this two-part series helps you plan TV production areas.
Ceiling systems
Figure 3. CNN studio ceiling detail
Click to enlarge
The space between the ceiling structural slab and the bottom of the lighting grid is by far the most complex coordination challenge in a TV studio. Here, one must interweave the HVAC distribution, acoustical absorption and isolation, electrical distribution, production lighting support and control systems, and rigging points for scenic elements, as well as the structural elements of the long-span studio roof. (See Figure 3.) The art in the design of this area is all about coordination of the many design professionals and trades people responsible for the various systems. Informed by the client's production requirements, it is the architect's responsibility to perform this coordination during the design process, and it is the general contractor's responsibility during the construction phase.
Some of the issues related to the ceiling will be covered in next month's article. However, issues such as lighting support systems and air distribution, which are future topics, have architectural, structural and acoustical implications, so some of those issues are worth mentioning now.
TV studios need wide open spaces without columns. Structurally, that implies long beams to span the space. Many times in my career, clients have enthusiastically shown me an existing large warehouse space, free of columns, only to find that that roof would have to be heavily reinforced at a substantial cost. This is because structures are typically designed to fulfill specific needs. A warehouse roof is designed to keep the rain out, whereas a TV studio roof has to carry a much greater load, in addition to the rain. That load can vary, depending on the size of the studio, the lighting supports strategies and the acoustical isolation to be hung from it.
Small studios are usually much less affected, because the spans are smaller. As studios become larger, such as those used for telenovelas, soap operas, audience variety shows and sitcoms, the weight-to-span ratio increases exponentially, meaning more weight in longer spans. In planning the studio as new construction, there is a benefit to being able to incorporate the structural components efficiently. Add allowances above code requirements for designs, including the following distributed loads: 7lbs per sq ft for acoustical isolation; 35lbs per sq ft for ducts; electrical and piping, and 25lbs per sq ft for the lighting and grid.
If you choose to use a lighting support system based on catwalks, another 30lbs per sq ft should be added. That puts the requirement somewhere between 67lbs and 97lbs per sq ft. We also recommend structural provisions for concentrated loads, as often productions need to hang heavy elements. The amount depends on the size of the studio. We typically plan for suspending a weight of 3000lbs from the areas dedicated to concentrated loads.
In large studios, there is typically a structural steel subframe below the acoustical barrier ceiling from which all other elements are hung. It is impractical to create a studio in which the structure is buried behind layers of acoustical construction. The subframe usually is made of steel beams 10in deep, creating a grid of 10ft to 12ft hung directly from the primary structure.
Ceiling considerations
The ceiling is the surface that completes the acoustical enclosure of the studio. In most cases, whether you have another occupied floor above you or just a roof, an isolated ceiling is necessary to maintain the acoustical standards established in the design criteria. The amount of mass and the qualities of the acoustical ceiling are subject to the recommendations of the acoustical consultant and can vary from a hung acoustic tile ceiling to a multilayer gypsum board ceiling. The ceiling, however, is always installed up to the interior wall of the studio and is never attached, allowing independent movement.
Often a ceiling has a layer of plywood and one layer or more of gypsum board, if required. Then the ceiling is suspended with a spring neoprene isolator. The isolators are typically located in two directions at 48in on center. Over the years, plywood has proven to be a practical material for the attachment of small speakers and to make the installation of the gypsum board more secure. Above the ceiling, it is important to provide a minimum of 6in fiberglass batt insulation to absorb sounds in the cavity. Below the ceiling, it is recommended that a minimum of 2in of absorbent material be installed.
The architect must work with the ventilation engineers and others to carefully coordinate the location of the isolators and the ducts. We usually create one drawing to show those locations, plus two more drawings to document the other ceiling information, because showing it all in one drawing creates clutter, making it impossible to read.
The ceiling area of a TV studio is congested, offers many challenges and has to be specifically tailored to the desired size and planned production needs. Many of the systems in this area will be covered in next month's article, which will review electrical systems lighting, power and systems integration (low voltage).
Antonio Argibay, AIA, is a principal of Meridian Design.
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