In building a structure, especially a dwelling, optimal room placement depends on a variety of factors. Two prime factors include the noise that is anticipated will be generated in a room and the plumbing and ventilation needed for that room. A most efficient way of designing a structure would place all plumbing in the structure in a centralized location, which would require the rooms needing plumbing to share walls, and to place rooms where there is likely to be a lot of noise away from rooms that require more silence. However, other considerations make the placements of these rooms undesirable, especially for kitchens and bathrooms. For example, it is generally undesirable for sounds in the bathroom to pass to the kitchen, both from a privacy standpoint of a person using the bathroom and from a desirablity standpoint of someone cooking and/or eating in the kitchen.
In general, the solution to the plumbing/noise issue has just been to deal with the extra plumbing and have the bathroom and kitchen in different areas of the house. However, this does not address the problem of streamlining plumbing. This especially remains an issue for pre-fabricated structures that require thin, strong walls and centralized plumbing. Similarly, for sound-proofing, typical solutions have required thick walls that are difficult, if not impossible, to pre-fabricate and transport to the construction site. Other solutions have suggested using sound-absorbing materials for walls separating rooms where it would be undesirable to have acoustic transfer. However, sound-absorbing material is typically thick or expensive, and simply is not useful for many pre-fabricated structures. Additionally, some walls are used to vent air, and those walls cannot be filled with sound-absorbing material. Thus, there is still a need for a thin, sturdy wall that is sound-proof.