Find Colocation, Dedicated Servers & Cloud Hosting:
Call Now (888) 400-5732

Cold or Hot Aisle Containment, Which Is Better?

Posted by QuoteColo on August 16, 2016 - Updated on August 16, 2016


Over the past few years, the data center industry has seen an increase in interest regarding containment. The result is a widespread implementation across many sites. In fact, the Uptime Institute took a survey that found that 80% of sites have implemented and adopted cold or hot aisle containment.

Perhaps you’re thinking about doing the same thing, but you aren’t sure which options makes the most sense, cold aisle or hot aisle containment. It’s definitely a big decision that will have huge ramifications, so before you start, consider the following.

Pros of Cold Aisle Containment

First, let’s look at the benefits of going with cold aisle containment. Right off the bat, it’s going to be easier to implement as it doesn’t require any modifications to your room in order to contain and return exhaust air into the cooling units. You also only need a cap at top and doors at ends.

As it’s going to be easier to implement, it should come as no surprise that cold aisle containment tends to be the more affordable version as well. If you do end up needing to retrofit it into a preexisting data center, this should be much easier to do too.

If you already have a raised floor in your data center – which is still very common – cold aisle containment is a great fit. Though, with a little work, it doesn’t need to be on a raised floor.

Finally, this method leaves more space for “cold sinks” – even without a raised floor – which will be a welcomed feature in the event of a power failure and generators not starting.

Pros of Hot Aisle Containment

Alright, now let’s look at the arguments for hot aisle containment starting with the fact that the open area of a room is already a cold environment. Any leakages from openings in the raised floor in the larger area are going to just end up there too.

Hot aisle containment will give you a greater margin of error for network racks. The same goes for standalone equipment like storage cabinets which could have to be kept outside of the containment structure (so in the lower temperature area of the room).

If you already have a slab environment, hot aisle containment can perform just fine by flooding the data center with a sufficient amount of supply air and then keeping a lid on the exhaust air.

Finally, simply by virtue of the fact that the containment design typically adjoins to the ceiling – which features fire suppression measures – the entire setup isn’t actually creating separate volumes. Instead, it’s just creating obstructions that have to clear sprinkler heads by a certain amount. Depending on the space, it’s possible that a standard grid fire suppression system could work around a hot aisle containment setup and still meet code just fine.

So Which One Is Better?

If it were possible to configure a computer room so that either of the above could be implemented, then, leaving aside all other factors, hot aisle containment would be the superior choice.

That being said, every single computer room is 100% unique. You have to consider the factors that make your room unique so that you can then figure out which of the above two options will be the most effective. For many of you, hot aisle containment simply won’t work out as well.

Therefore, our recommendation is to assess your site, looking at its pros and cons relative to the information we just covered and taking bypass airflow into consideration. Then, and only then, will you be able to make a sound choice about cold or hot aisle containment.

Categories: Data Center

What Do You Think?