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buffalobillpatrick · 11-19-14, 12:57 PM

"EPS labeled at R19 will be performing at about R21 in mid-winter in a US zone 7 location (at the typical average temp through the foam, 70F interior temp), whereas iso labeled at R21 under ASTM test conditions would be performing at about R19."
Dana1

"Since nobody has mentioned it I'll state for the record, you should never (and I mean NEVER!!) use polyiso under a slab, or between a foundation-wall and soil. But it's OK to use on the interior side of open basements. Iso is mildly hyrgroscopic, and will wick & store moisture over time, if it gets regular exposure.

Initial moisture uptake of EPS is faster than XPS (due to the interstitial spacing between beads), but at comparable densities has higher fraction of fully closed cells, making it somewhat better at handling long term moisture exposure. Even at 7% moisture content it still retains most of it's R value, as indicated in sailawayrb's industry references.

Both EPS and XPS have significant derating/uprating curves with temperature. In the US the legally labeled R value of Type-II EPS is R4.2/inch when the average temperature through the material is 75F, but the tested R value goes up at lower temps, down with higher temps. In a heated slab where the bottom side of the slab is 85F and the subsoil temp is 55F, it's performance is somewhat better than labeled.

The derating/uprating curves for XPS are similar, but not as pronounced as with EPS, at least early in it's lifecycle. Freshly blown it's R-value is about R7/inch @ 75F, but that falls fairly quickly (months, a couple of years at most) to under R5.5/inch, with a much slower decline over time from there. It is allowed to be labeled at R5/inch by it's average performance over some presumed lifecycle (IIRC it's 25 years, but don't count on that.) It's fully depleted R-value of 1.5lb XPS is identical to Type-II EPS. In under 50 years any performance difference would be largely theoretical (and miniscule.)"
Dana1

According to Insulation Corporation of America: “Expanded polystyrene (EPS) is the winner! This was clearly shown in an independent, third-party test. Expanded polystyrene (EPS) maintains its R-value even after long-term exposure in northern climates. Extruded polystyrene (XPS) was shown to have lost R-value over time. In this 15 year side by side dual EPS outperforms XPS in both R-value retention and decreased water absorption. XPS insulation was reduced by half, while EPS boasts maintaining 94% of its specified R-value. Not only does XPS lose about half of their R-value it also costs about 50% MORE than EPS. So why would anyone pay 50% more for 50% less? EPS is manufactured in large blocks, it is cut into sheets or virtually any special size and shape. XPS is a final form and does not have the size flexibility that EPS offers. The product performance, size flexibility, recyclability, and the lower price of our “white stuff” clearly makes EPS the champion.”

"The International Building Code (IBC) and International Residential Code (IRC) are the predominant building codes. These codes rely on the American Society of Civil Engineers (ASCE) 32-01 standard to determine appropriate thermal properties of XPS and EPS used for below-ground building applications for long-term protection against frost heave. ASCE 32-01 shows that nominal 5.0 R per inch XPS effectively becomes 4.0 after long-term exposure when used horizontally (retains 80% of original nominal R-value). Nominal 4.0 R per inch EPS effectively becomes 2.6 after long-term exposure when used horizontally (retains 65% of original nominal R-value). Nominal 5.0 R per inch XPS effectively becomes 4.5 after long-term exposure when used vertically (retains 90% of original nominal R-value). Nominal 4.0 R per inch EPS effectively becomes 3.2 after long-term exposure when used vertically (retains 80% of original nominal R-value)."

NOTE: Above is in the IBC Building Code, but is not correct or supported by un-biased testing!

So, relative to Rigid Cellular Polystyrene (RCPS) thermal properties, both products may be successfully used provided one uses the appropriate long-term R-value in the design. We use the ASCE 32-01 values. Of course one also needs to consider RCPS structural properties in the design to avoid building slab settling. This is always important and becomes increasing critical when you are designing a hydronic radiant heating system for a building in Anchorage for example with many inches of RCPS.

to glue foam to clean concrete

http://www.styro.net/PDF/Flyers/Flexcoat%20Flyer.pdf

glue foam to foam: Glidden gripper

GREAT INFO

http://www.greenbuildingadvisor.com/...-basement-wall
Briefly, how are basement walls insulated on the exterior?

After the basement wall has been protected with a dampproofing or a waterproofing system, insulation is installed from the top of the footing to somewhere near the top of the rim joist. Acceptable insulation materials include extruded polystyrene (XPS), expanded polystyrene (EPS), closed-cell spray polyurethane foam, or mineral wool. Polyisocyanurate insulation should not be used because it can absorb water.

Below-grade insulation does not need to be attached to the concrete; it is held in place by the backfill. The best backfill material is a fast-draining granular material like gravel or crushed stone with a thin cap of soil or clay.

Above-grade insulation may or may not need to be attached to the concrete — fastening methods include foam-compatible adhesive, TapCons with washers, and specialty fasteners like Hilti IDP fasteners or Rodenhouse Plasti-Grip PMF fasteners — depending on the height of the exposed foam and the method used to protect it.

Some builders cantilever their 2x6 perimeter walls so that the basement insulation isn't proud of the siding. If the basement insulation ends up proud of the siding, you'll have to protect the top of the basement insulation with metal flashing. The top of the flashing needs to include a vertical leg that extends upward and is lapped by the housewrap; the flashing should be sloped, and the bottom of the flashing needs to terminate in a drip leg that extends beyond the insulation and the insulation protection materials.

If I insulate on the outside, how should I protect the above-grade foam?

The above-grade portions of all types of exterior insulation must be protected from physical abuse and sunlight. Among the products than can be used for this purpose are the following:

A cementitious coating or cementitious stucco (for example, Styro Industries Brush On ST), with or without metal lath
A cementitious coating that includes chopped fiberglass (for example, Quikrete #1219 foam coating or surface-bonding cement)
An acrylic coating like Styro Industries FlexCoat or Styro Industries Tuff II
EIFS (synthetic stucco)
Cement backerboard, with or without a layer of stucco
Pressure-treated plywood
Metal flashing
A fiberglass panel like Ground Breaker from Nudo Products
Styro Industries FP Ultra Lite panels (XPS coated with mineral granules adhered to one side)
Protecto Wrap Protecto Bond (a flexible peel-and-stick membrane with a textured, gritty coating)
ProGuard Cement Faced Insulated Sheathing.

For more information on this topic, see How to Finish Exterior Foundation Insulation.

11-19-14, 12:57 PM	#22
buffalobillpatrick Master EcoRenovator Join Date: Mar 2014 Location: Florissant, Colorado Posts: 599 Thanks: 814 Thanked 59 Times in 55 Posts	"EPS labeled at R19 will be performing at about R21 in mid-winter in a US zone 7 location (at the typical average temp through the foam, 70F interior temp), whereas iso labeled at R21 under ASTM test conditions would be performing at about R19." Dana1 "Since nobody has mentioned it I'll state for the record, you should never (and I mean NEVER!!) use polyiso under a slab, or between a foundation-wall and soil. But it's OK to use on the interior side of open basements. Iso is mildly hyrgroscopic, and will wick & store moisture over time, if it gets regular exposure. Initial moisture uptake of EPS is faster than XPS (due to the interstitial spacing between beads), but at comparable densities has higher fraction of fully closed cells, making it somewhat better at handling long term moisture exposure. Even at 7% moisture content it still retains most of it's R value, as indicated in sailawayrb's industry references. Both EPS and XPS have significant derating/uprating curves with temperature. In the US the legally labeled R value of Type-II EPS is R4.2/inch when the average temperature through the material is 75F, but the tested R value goes up at lower temps, down with higher temps. In a heated slab where the bottom side of the slab is 85F and the subsoil temp is 55F, it's performance is somewhat better than labeled. The derating/uprating curves for XPS are similar, but not as pronounced as with EPS, at least early in it's lifecycle. Freshly blown it's R-value is about R7/inch @ 75F, but that falls fairly quickly (months, a couple of years at most) to under R5.5/inch, with a much slower decline over time from there. It is allowed to be labeled at R5/inch by it's average performance over some presumed lifecycle (IIRC it's 25 years, but don't count on that.) It's fully depleted R-value of 1.5lb XPS is identical to Type-II EPS. In under 50 years any performance difference would be largely theoretical (and miniscule.)" Dana1 According to Insulation Corporation of America: “Expanded polystyrene (EPS) is the winner! This was clearly shown in an independent, third-party test. Expanded polystyrene (EPS) maintains its R-value even after long-term exposure in northern climates. Extruded polystyrene (XPS) was shown to have lost R-value over time. In this 15 year side by side dual EPS outperforms XPS in both R-value retention and decreased water absorption. XPS insulation was reduced by half, while EPS boasts maintaining 94% of its specified R-value. Not only does XPS lose about half of their R-value it also costs about 50% MORE than EPS. So why would anyone pay 50% more for 50% less? EPS is manufactured in large blocks, it is cut into sheets or virtually any special size and shape. XPS is a final form and does not have the size flexibility that EPS offers. The product performance, size flexibility, recyclability, and the lower price of our “white stuff” clearly makes EPS the champion.” "The International Building Code (IBC) and International Residential Code (IRC) are the predominant building codes. These codes rely on the American Society of Civil Engineers (ASCE) 32-01 standard to determine appropriate thermal properties of XPS and EPS used for below-ground building applications for long-term protection against frost heave. ASCE 32-01 shows that nominal 5.0 R per inch XPS effectively becomes 4.0 after long-term exposure when used horizontally (retains 80% of original nominal R-value). Nominal 4.0 R per inch EPS effectively becomes 2.6 after long-term exposure when used horizontally (retains 65% of original nominal R-value). Nominal 5.0 R per inch XPS effectively becomes 4.5 after long-term exposure when used vertically (retains 90% of original nominal R-value). Nominal 4.0 R per inch EPS effectively becomes 3.2 after long-term exposure when used vertically (retains 80% of original nominal R-value)." NOTE: Above is in the IBC Building Code, but is not correct or supported by un-biased testing! So, relative to Rigid Cellular Polystyrene (RCPS) thermal properties, both products may be successfully used provided one uses the appropriate long-term R-value in the design. We use the ASCE 32-01 values. Of course one also needs to consider RCPS structural properties in the design to avoid building slab settling. This is always important and becomes increasing critical when you are designing a hydronic radiant heating system for a building in Anchorage for example with many inches of RCPS. to glue foam to clean concrete http://www.styro.net/PDF/Flyers/Flexcoat%20Flyer.pdf glue foam to foam: Glidden gripper GREAT INFO http://www.greenbuildingadvisor.com/...-basement-wall Briefly, how are basement walls insulated on the exterior? After the basement wall has been protected with a dampproofing or a waterproofing system, insulation is installed from the top of the footing to somewhere near the top of the rim joist. Acceptable insulation materials include extruded polystyrene (XPS), expanded polystyrene (EPS), closed-cell spray polyurethane foam, or mineral wool. Polyisocyanurate insulation should not be used because it can absorb water. Below-grade insulation does not need to be attached to the concrete; it is held in place by the backfill. The best backfill material is a fast-draining granular material like gravel or crushed stone with a thin cap of soil or clay. Above-grade insulation may or may not need to be attached to the concrete — fastening methods include foam-compatible adhesive, TapCons with washers, and specialty fasteners like Hilti IDP fasteners or Rodenhouse Plasti-Grip PMF fasteners — depending on the height of the exposed foam and the method used to protect it. Some builders cantilever their 2x6 perimeter walls so that the basement insulation isn't proud of the siding. If the basement insulation ends up proud of the siding, you'll have to protect the top of the basement insulation with metal flashing. The top of the flashing needs to include a vertical leg that extends upward and is lapped by the housewrap; the flashing should be sloped, and the bottom of the flashing needs to terminate in a drip leg that extends beyond the insulation and the insulation protection materials. If I insulate on the outside, how should I protect the above-grade foam? The above-grade portions of all types of exterior insulation must be protected from physical abuse and sunlight. Among the products than can be used for this purpose are the following: A cementitious coating or cementitious stucco (for example, Styro Industries Brush On ST), with or without metal lath A cementitious coating that includes chopped fiberglass (for example, Quikrete #1219 foam coating or surface-bonding cement) An acrylic coating like Styro Industries FlexCoat or Styro Industries Tuff II EIFS (synthetic stucco) Cement backerboard, with or without a layer of stucco Pressure-treated plywood Metal flashing A fiberglass panel like Ground Breaker from Nudo Products Styro Industries FP Ultra Lite panels (XPS coated with mineral granules adhered to one side) Protecto Wrap Protecto Bond (a flexible peel-and-stick membrane with a textured, gritty coating) ProGuard Cement Faced Insulated Sheathing. For more information on this topic, see How to Finish Exterior Foundation Insulation. Last edited by buffalobillpatrick; 11-19-14 at 01:08 PM..