Polycom 2457-26122-001 User Manual

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Room Design and Layout
Polycom, Inc. 
237
 
In order to guarantee that the final conference environment will have a solid 
foundation, we begin with the construction of the walls, floors and ceilings for 
videoconference spaces. 
Walls
Conference room walls should be built from slab to slab. That is, there should 
be no gaps from the concrete of one floor to the concrete of the next floor. 
Resilient, gypsum board mountings should be used to close any gaps. The 
thickness of the gypsum board should be 5/8” or more (one layer of 5/8” and 
one layer of 1/2” bonded together would be ideal) on the inside of the room, 
with 1/2” thick (or as required by local building codes) appropriate for the 
outside of the walls. There should always be a difference in thickness between 
the materials used on the inner versus the outer walls. That difference in 
thickness subdues mechanical coupling (vibration) between the two layers. A 
good overall wall thickness is 6”. It is recommended that “offset stud” 
construction be used, typically a 6” header and footer with 3.5” verticals 
attached in an alternating pattern one toward the outside of the footer, the next 
toward the inside and so on.
Fiberglass dense batting or mineral rock wool, 4” to 6” thick (the equivalent of 
R-11 to R-13) should be placed in the wall space. The thickness of the batting 
is not critical. The critical aspect is that it must be loosely placed in the wall 
space, not compacted to fit. The resultant wall will have excellent acoustic 
isolation from the outside world. More significant acoustic isolation can be 
achieved by placing an additional barrier layer within the wall space. 
Typically this barrier will be made of a dense polymer material, about 1/8” 
thick, and the improvement regarding loss of sound transmitted through the 
wall will be roughly a factor of 10. These materials are available from a variety 
of manufacturers.
Windows
Windows usually present the equivalent of an acoustic nightmare (as well as 
altering the way a camera renders colors and brightness). They not only 
transmit room sound, but also allow unwanted outside noise to intrude on the 
conference space. In the event that windows cannot be avoided, it becomes 
essential that window treatment of some sort be used. This treatment should 
match the interior look and feel of the space, while providing a high level of 
sound and light block. Typically a heavyweight drape (24 ounces or more) of 
heavy fullness (not less than 6” fullness on not less than 8” centers per fold) is 
preferred. In all cases, the use of sheer draperies or standard vertical or 
horizontal blinds should be avoided, due to their inherent inefficiency in 
blocking sound and light, and the fine lines they create within the camera field 
of view.