Data Center Cold Aisle Containment

Designing the System

Once you’ve considered all the impediments to successful aisle containment, the next step is to actually develop the design.

Hot Aisle or Cold Aisle Containment?

The first decision is choosing between hot or cold aisle isolation. There are pros and cons to each and often the decision is based on which yields a better or easier containment installation. The argument for cold aisle containment is you presumably cool less air. Only the air in the cold aisle remains cool while everything else in the room is allowed to warm.

Ironically, this is the same reason some people like hot aisle containment; by keeping the entire room except the hot aisles cool, you create a cold air capacitor which can help you ride out a short duration cooling system interruption.

Initial Containment Layout

With either hot aisle or cold aisle containment, the preferred layout is to align the containment walls with the cold face of the rack. The motivation for this is the isolation plane is at the cold face of the rack. Any air behind the cold face is presumed hot and any cutouts or perforations in the top of the rack will allow the hot air to escape. If the containment walls are along the cold face, the escaping hot air stays on the hot side of the curtain.

How High?

Next, will your containment go all the way to the ceiling? This decision point will help you determine the length of the containment between the cabinets or racks and the support rail at the ceiling. Depending on the cooling configuration and the ceiling height, the containment walls do not have to go all the way to the ceiling to be effective.

How to Support the Containment System?

Containment systems can be supported in a variety of ways. Some ways are specific to some systems while other are common to all.

Lightweight systems like curtains and certain hardwall systems can be supported from a standard commercial ceiling grid. Heavier systems are typically supported from the building structure above the ceiling or the floor or from the equipment racks themselves. Door systems typically rest on the floor and attach to the equipment racks or building structure above for stability. Understanding how your containment system will be supported is critical to the layout and overall design.