Separation of Hot and Cold Aisle
The photograph above was taken in BT’s Rochdale Data Centre. It shows the use of curtains to separate the hot and cold aisles, thereby reducing the amount of hot air that mixes with cold air from the plenum floor and dramatically increasing cooling efficiency. Inside the curtained off space are all of the open vents from the plenum floor and all of the cabinet fronts.
In combination with the curtains, each cabinet is fitted with blanking plates to ensure that the only path for cold air to pass is via a piece of equipment. Missing cabinets and missing equipment offers an alternative route for airflow that causes hot and cold air to mix reducing air handling efficiency.
The delta in temperature between the air inside the curtained off area and that outside is quite dramatic, being in the range of 10° to 15° Celsius. Refrigeration efficiency is increased by approximately 20%.
Installing curtains and organising cabinets and open floor tiles in a sensible way is something that everyone can do regardless of the age and condition of their data centre site. If the site is constrained by cooling capacity, the installation of curtains will allow more equipment to be installed. As a minimum the energy bills will drop markedly.
Another photograph of BT’s Rochdale Data Centre, this time from inside the cold aisle.




Pingback by Telecommunications companies have used fresh air cooling for decades for their network equipment in telephone exchanges. Vendors manufacture most of their computer products to operate in this environment. | The Hot Aisle on 6 June 2008:
[...] be installed. It is very important to utilize hot and cold aisle separation preferably using curtains as described in my earlier post. “According to technical specification of several manufacturers products (servers and telco [...]
Comment by Mark Frenette on 11 July 2008:
Is there a vendor that sells these curtains or did you have to make them? I can’t seem to find any online.
Comment by Steve O'Donnell on 11 July 2008:
Mark
Stop looking in the data center catalogues. They come from industrial product companies. Drive in deep freeze, hospital and food preparation applications. I will get the part numbers and suppliers and publish them here.
In fact I suspect that a new article is called for covering fire suppression and hanging.
Steve
Steve
Pingback by The safety of personel working within the data center is absolutely critical and there are a number of key issues to be concerned with: | The Hot Aisle on 11 July 2008:
[...] I had two great questions from Hot Aisle readers following the latest article on Cold Aisle containment. Dan asked about the impact on fire suppression and Mark asked about where we got the transparent curtains. [...]
Comment by Randall Fruge on 14 July 2008:
Just wondering if you have finished your article on fire supression and the curtains. How were you able to work around the sprinkler heads and appease the Authorities having jurisdiction.
Comment by Steve O'Donnell on 15 July 2008:
Hi Randall
I have been busy over the last few days writing articles so perhaps you missed it in the mix. Try http://www.thehotaisle.com/2008/07/11/using-curtains-to-manage-data-center-airflow-revisited/
Hope that does it for you.
Best
Steve
Comment by Del Marks on 14 August 2008:
Mark,
TRAX Industrial Products is a leader in cold aisle containment solutions for data centers. We have been a manufacturer of flexible environmental and contamination control barriers ie: industrial curtains, for almost 30 years. We have several data center installations currently in operation. We welcome your inquiry and would be happy to share our knowledge.
Regards,
Del Marks
Sales Manager
TRAX Industrial Products Corporation
Comment by thehotaisle on 1 September 2008:
Hi Del,
Thanks for your reply. TRAX have certainly got some interesting products in the Data Center Curtains area and they can be found at http://www.traxindprod.com/
Steve
Comment by John on 21 October 2008:
This is a solution that works, even Yahoo are using it. http://www.Keyzone.com who specialise in providing Data Center solutions such as KVM Switch, Server Rack etc. have recently introduced a Cold Aisle Containment service that makes use of these curtains. Keyzone (020 900 1525) offers a site survey and onsite trial of the curtains. I am sure if you have a big enough requirement they will offer a free of charge trial.
Comment by John on 21 October 2008:
This is a solution that works, even Yahoo are using it. http://www.Keyzone.com who specialise in providing Data Center solutions such as KVM Switch, Server Rack etc. have recently introduced a Cold Aisle Containment service that makes use of these curtains. Keyzone (020 900 1525) offers a site survey and onsite trial of the curtains. I am sure if you have a big enough requirement they will offer a free of charge trial.
Comment by John on 9 March 2009:
My suggestion is not to look at industrial product companies but to talk to people who are used to working in data centres. I have used http://www.keyzone.com/Data_Centre_Solutions.htm (020 8900 1525) on a couple of jobs with very good results. They offer this system for any racks that you may have but as I had a new install I went with their approved racks. The curtains fit on to their approved racks better then standard racks and they also have vertical barriers for within their cabinets.
This system pays for it self within a few months for most average size data centres, I read some where that Yahoo estimated that they would save £1million per year if they installed this in one of their data centre (they already have a small install).
Comment by John on 9 March 2009:
My suggestion is not to look at industrial product companies but to talk to people who are used to working in data centres. I have used http://www.keyzone.com/Data_Centre_Solutions.htm (020 8900 1525) on a couple of jobs with very good results. They offer this system for any racks that you may have but as I had a new install I went with their approved racks. The curtains fit on to their approved racks better then standard racks and they also have vertical barriers for within their cabinets.
This system pays for it self within a few months for most average size data centres, I read some where that Yahoo estimated that they would save £1million per year if they installed this in one of their data centre (they already have a small install).
Trackback by Scott Hanson on 5 June 2009:
Interesting .. RT @AustinCTO: Curtains in the datacenter? Check these out http://tinyurl.com/a5jtl4. Can I get mine with fish?
Pingback by NetApp get their internal data center strategy right | The Hot Aisle on 26 August 2009:
[...] To support the data center’s efficient use of airflow, plastic curtains are used to separate the front of the racks from the back. (These are exactly the same curtains that we used at BT some years ago and I blogged about on The Hot Aisle) [...]