Between Floors And Ceilings

A plenum is an enclosed portion of the building structure that is designed to allow the movement of air, forming part of an air distribution system. The term plenum is specifically used for the chamber at the top of a furnace, also called a bonnet, from which ducts emerge to conduct heated or conditioned air to the inhabited spaces of the building. It is also commonly used to refer to the open area between the bottom of a floor structure and the top of the ceiling assembly below. In some cases, air is carried through this space without ducting, a design called an open plenum.

Building codes limit where open plenum systems can run in a building, prohibit combustible materials in plenum spaces, and allow only certain types of wiring. Equipment in the plenum sometimes continues vertically down a structurally created shaft. The open plenum must be isolated from other spaces so that debris in the plenum and vertical shaft is not drawn into a return air intake.

The area between the floor above and ceiling below ¿( is usually full of electrical, plumbing, heating and cooling, lighting, fire suppression, and other equipment (Fig. 3-1). As an interior designer, you will often be concerned with how you can locate lighting or other design elements in relation to all the equipment in the plenum.

Designing for Building Functions 19

Suspended

Ceiling

Support

Suspended Ceiling Tiles

Suspended Ceiling Tiles

Figure 3-1 Floor/ceiling assembly.
Solar Power

Solar Power

Start Saving On Your Electricity Bills Using The Power of the Sun And Other Natural Resources!

Get My Free Ebook


Post a comment