Replies

1. 
   brendanalbano | Jan 05, 2017 12:54pm | #1

   The greenness of EPS (expanded polystyrene) is usually discussed in relation to XPS (extruded polystyrene). The key difference is that the blowing agents used in XPS have typically a significantly higher global warming potential than the blowing agents used in EPS.

   So if you're concerned about the environmental impact of your building, and you have a need for rigid foam board, EPS is typically a greener choice than XPS.

   I say typically because I believe the blowing agents used in XPS vary in different parts of the world.

   There are no doubt even greener approaches to insulation that using rigid foam (it's still a petrochemical product), but they are often either expensive or not practical for other reasons, depending on the project. If you have to use foam (and you often do), EPS is usually less bad than the alternatives.

   Using recycled foam (of any type) is the greenest foam of all.

   edit: This is from a U.S. perspective, so the manufacturing methods of foam may be different where you are building.

2. GBA Editor
   Martin Holladay | Jan 06, 2017 06:49am | #2

   Rich,
   It's hard to pin down a definition of "green building." One thing is for sure: what seems "green" in one country may not be green in another. To determine what is green in your country, you have to start by researching what materials are locally available, and then consider their price and the distance these materials have traveled to reach your construction site.

   Finally, any analysis of the "greenness" of insulation has to consider:
   (a) how much energy is used for space heating and cooling,
   (b) whether the insulation reduces that energy enough to make the installation of the insulation logical, and
   (c) whether the production of that energy involves significant greenhouse gas emissions.

   In other words -- it's complicated.

3. 
   charlie_sullivan | Jan 06, 2017 12:42pm | #3

   Picking up on Brendan's comparison to XPS, here in North America, green builders avoid XPS because all the XPS available here is made with blowing agents that have a high global warming potential, around 700 to 1400 times higher than CO2.

   However, in your region, I see that at least a few XPS suppliers are offering XPS with low global warming potential. At that point, the green attributes of XPS and EPS become much more similar, and which is greener probably equates to whichever is cheaper, because you can then buy more of it and use a thicker layer of insulation, reducing energy use for your building.

   Specifically, Kingspan offers that H series, which has high global warming potential, or the N series which has low global warming potential, so the N series would be a much better choice. (http://www.kingspaninsulation.ae/products/styrozone/)

   And Isofoam offers "Isoboard" with high global warming potential, and "Isoboard Green" which has low global warming potential. http://www.isofoam.ae/isoboard-green-products-dubai-isofoam.php

4. 
   Rikma | Jan 09, 2017 11:30am | #4

   Thank you for the valuable responses.
   regarding the comments on blowing agent I searched further and found this detailed article on the blowers used in the manufacturing of Extruded Polystyrene. http://www.nppfdubai.com/en/home/printurl/contents/view/go-green.html

   It says that the manufacturing of EPS scores well with GWP (Global Warming Potential) and ODP (Ozone Depletion Potential).

   It seems NPPF (national Polystyrene Packaging Factory Dubai ) is using a blowing method which is HFC, CFC, and HCFC free and Pentane is used as its blowing agent.

5. 
   Rikma | Jan 09, 2017 11:39am | #5

   This site says that water/steam ( http://www.ptonline.com/articles/water-blown-eps-will-help-you-and-the-environment ) blown EPS is more Eco-friendly and greener than other EPS blown using chemical agents