Under Floor Air Distribution - (UFAD) The cleanest air delivery method!
Thanks for clicking on this blog post guys! Todays blog post is a topic that that I have held off discussing as we have heard so much talk lately around indoor air quality, airborne virus’, air circulation etc. However, this notion of under floor air distribution is something I have been a part of promoting for almost 12 years now, and it is something that I feel very strongly about and something I do truly believe in - hence, why I would like to share some of my thoughts and my experiences with you guys here today.
First of all, let me begin by telling you a little about my history and education, I started in the raised floor and under floor air business approx. 12 years ago, coming out of the trades and working my way into a sales/project manager role under the leadership of a couple P.Eng’s and a highly motivated sales team leader. From there I continued my education and completed my Advanced Diploma in Mechanical Engineering, and I am now waiting on my final exam for a CET designation.
Within the last 12 years myself and my incredible team (who you will meet in the next blog, titled, “meet the team”) have worked on close to 4 million square feet of raised access floor and under floor air distribution projects! Most recently we completed a 40,000sqft project, encompassing raised floor and a full UFAD system! It is very important to have a solid team installing the raised floor, especially when dealing with an UFAD system - check out the previous blog post for all the reasons why…
Back to the topic at hand UFAD - what is UFAD? Simply put, the space/void created by the raised access floor system allows for the free distribution of conditioned air, exiting out of strategically placed vents throughout the floor plate. This differs to the traditional method of delivering the air from overhead. The OH method is also known as the “mixing” method, meaning to achieve the desired fresh air levels and set points requested by the thermostat, the fresh, conditioned air is designed to mix with the existing room air - hence the term “mixing systems.” This means that any contaminants, pollutants, germs etc. that exist within the space are generally recirculated over and over again, throughout the day. The difference with a UFAD approach, is we see very little stratification of room air, meaning we see very little mixing of room air simply because the air is introduced below the occupants feet, and due to simple physics (hot air rises) the cool, conditioned air naturally pushes the existing room air up and out of the occupied zone, and eventually back the mechanical system for filtration and recirculation.
Check out an amazing video on this concept here; https://youtu.be/ZjbvXeNMXj8
Before I continue, I must add that there are hundreds of published papers on this matter, from PH.D’s, engineers, researchers, and scholars alike, from institutions like Harvard, Purdue and most notably the Center for the Built Environment at Berekly, Fred Bauman, who has spent many years leading a research team into the benefits of UFAD systems. Fred' was the author of the first ever UFAD design guide published by ASHRAE in 2003 - that’s a big deal for anyone in the HVAC world!
Because there is far less mixing of the air when delivered by the UFAD method, the pollutants and contaminants remain in the space above the “occupied zone” (this being the space in 6’ or above off the floor). The occupied zone is that of the breathing area, from 2’-6’, typically reserved for sitting and/or standing whilst inside a space. What we refer to as, “toes to nose.”
There is a very important term, “ventilation effectiveness” this term describes the systems ability to remove pollutants generated by internal sources in a space, zone or building. (ASHRAE UFAD guide, 20003) This term is important to note as UFAD systems provide better “ventilation effectiveness” when measured within a space than that of overhead systems.
If having a raised access floor coupled with a UFAD system provides a healthier and happier workspace, also allowing the freedom and flexibility to adapt, grow and change organically, with very little cost to construction - and all of these attributes can be achieved at the same cost to that of traditional construction methods, why would anyone choose to build any other way?
As I discuss RAF and UFAD with other industry experts, it is becoming apparent that in European countries, Australia, and even in the Eastern parts of Canada and throughout the US, there is a bigger shift to UFAD and RAF, this is encouraging as we truly do feel it is the best way to build out and interior space.
Thank you again for checking into this blog post, we really appreciate the support - if you have any questions we would be happy to sit down (virtually for now) and discuss with you!
