EPS foam for loadbearing applications “Geofoam”
![](https://secure.gravatar.com/avatar/bdb5cb691ec733567453079262e8d2de?s=52&d=https%3A%2F%2Fimages.greenbuildingadvisor.com%2Fapp%2Favatars%2F200x200%2Fj.png&r=g)
I found a bit of info today that I thought I ought to share. There is actually a standard for EPS used in structural applications (like under a footer). The standard I usually see is ASTM C578, which specs “Type I”, “Type II”, etc. There’s a second standard, ASTM D6817, which gives a requirement for compressive resistance at 1% deformation, the maximum safe pressure for long term loads.
I found one manufacturer’s nice little cross reference between the standards at http://www.styrotech.com/downloads/EPS-DataSheet-ASTM-D6817.pdf
This document gives some background for why 1% is the safe compression: http://tstark.net/wp-content/uploads/2012/11/82c-Geofoam-BearingCapacity-BCR2A-2009.pdf
I would always consult an engineer before designing in structural foam, but I think this is useful knowledge for exploring new designs. It’s at least a better starting point than the not-very-useful 10% deformation pressures that have been thrown around.
–John
GBA Detail Library
A collection of one thousand construction details organized by climate and house part
![](https://www.greenbuildingadvisor.com/app/themes/greenbuildingadvisor/dist/img/modules/detail-library/thumb1.png)
![](https://www.greenbuildingadvisor.com/app/themes/greenbuildingadvisor/dist/img/modules/detail-library/thumb2.png)
Replies
John,
Thanks. That's very useful.