I have no detailed knowledge about framing and I have to build this walk in chamber inside a lab for an experiment of mine. The lab ceiling has an I beam running its length, and also some water pipes hanging on the ceiling, which restrict the height of our chamber. The total available height for the chamber now is 120-122". More-over the chamber is to be lined in with wedges which are 13.5" in depth. Since we have to vibrationally damp the chamber, that reduces another 5". Since we need a walk-in chamber, it must atleast be 6', and since the chamber inner dimension is a multiple of the wedge (anechoic wedges), and adding the depth of wedges of the floor and the ceiling, i get a total height (minus framing ad vibrational damping) of around 111". Adding 5" for vibrational damping, I am left with only 4-6" for the framing of both the floor and the ceiling. Considering that and still trying to make it a walk-in chamber, I have very little left for the framing. I tried putting 2x4 studs flat for the roof, with the 2" dimension height-wise, and my calculations gave me a deflection of 0.5". Can I enforce it somehow without increasing the height of framing?
The chamber is an anechoic chamber but it doesnt need to be completely sound proof since it is inside another room. I cannot add a column as the interior of the chamber has to be obstruction free. There is nothing on the roof apart from the wegdes, 500lbs worth of which are on the roof.
The chamber exterior plan is 3.2x3.4 m