2016年2月5日 · Rigid foam manufacturers are required to perform R-value tests using an ASTM method specifying that the test be performed at a mean temperature of 75°F. At lower mean temperatures, EPS and XPS perform better than their R-value label indicates. In other words, as the temperature drops, the ability of EPS and XPS to resist heat flow improves.

2017年12月6日 · Q. "Is there any advantage to using XPS rigid foam as opposed unfaced EPS?" A. The only advantage is that XPS has a higher R-value per inch. The big disadvantage is the XPS damages the atmosphere. Q. "Is the permeability of 2 inch EPS an issue?" A. No.

GPS is usually rated at R5 per inch, just like XPS, but it's more stable over time than XPS is. EPS is about R4.2 per inch. None of those (GPS, EPS, XPS) need to be derated for cold weather. I really don't think polyiso needs to be derated in most cases, either. Building inspectors are just going to look at the labeled R value of the product.

2020年1月26日 · Comparative flammability of EPS, XPS, and polyiso rigid foam bluesolar | Posted in Green Products and Materials on January 26, 2020 11:41pm Hi all — Do EPS, XPS, and polyiso have different fire characteristics?

2014年5月2日 · Hi. I am back and forth on whether I should use XPS (blue board) or EPS for the insulation underneath my slab. I understand the qualities of each regarding water absorption and drying out, but would it (XPS particularly) affect the long term performance to the point where the slab is compromised? I also understand the pollution associated with XPS manufacturing. I …

2019年3月18日 · XPS vs. EPS vs. polyiso shrinkage rates lance_p | Posted in Energy Efficiency and Durability on March 18, 2019 02:39pm I’ve done some searching and found lots of claims about foam panels shrinking but have yet to see any hard numbers comparing the shrinkage rates for the big three foam types.

2018年3月28日 · (EPS has stable performance over decades, XPS does not.) Cutting 2" EPS is pretty easy using a 4-5" taping knife sharpened on the sides and a straight edge, but anything with a facer still requires a bit more care in cutting. Type-I EPS is often a PITA to deal with, since it usually comes with facers, but is TOO easy to break.

2019年3月16日 · Nathan is right. EPS is fine, and the vapor permeance of the foam is irrelevant. (This type of wall is designed to dry to the interior, not the exterior.) For more information on the building science concepts behind this type of wall, see "Calculating the Minimum Thickness of Rigid Foam Sheathing."

2009年9月28日 · Both XPS and EPS have been used successfully below grade, but XPS is still the standard because it typically has more compressive strength and higher R-value per inch. Your thermal design program should specify a certain required R-value for sub-slab insulation rather than a certain thickness. 3" of EPS would offer no more than R-12, while the ...

2013年6月24日 · Both XPS and EPS rise in R-value with falling temperatures, but with slightly different up-rating curves. Somewhere around -10F average temp through the foam (something you'll never see in fairly temperate Juneau, but might in Fairbanks with a 40F crawlspace) they're pretty much identical in R-value at a given thickness.