Table of Insulation Material R-Values & Other Materials' Insulating Properties

INSULATION R-Values & Properties - insulation materials R-values, rates of heat loss or gain, flame spread, toxicity, durability
- What insulation "R" values should be used in a building insulation?
- Insulation R-Values of materials found in or on buildings
Questions & Answers about the insulating properties of various materials
References

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This article provides a Table of Insulation Values and Properties for Various Insulation Materials useful in procedures to measure or calculate heat loss in a building, defines thermal terms like BTU and calorie, provides measures of heat transmission in materials, building insulation design data, and heat loss in a building. Page top photo by the author. Formula-R and Owens Corning which may be visible in this photograph of pink Styrofoam insulation boards are registered trademarks of Owens Corning and were photographed at a Home Depot® building supply center.

Table of Characteristics of Various Insulating Materials: fiberglass, mineral wool, cellulose, foam insulating board, UFFI, vermiculite, others

Because no amount of insulation can keep a drafty building warm, also review ENERGY SAVINGS PRIORITIES. See BLOWER DOORS & AIR INFILTRATION for a discussion of measuring air leakage in buildings. Also see HEAT LOSS INDICATORS (where is the building losing heat during the heating season, or gaining un-wanted heat during the cooling season), and see HEAT LOSS R U & K VALUE CALCULATION for a guide to calculating heat loss (or gain) rates for buildings and building insulation.

Table of Insulation & Other Building Material Properties
Insulation or other Building Material ⁹	R-Value¹	Density²	Perm³	Absorption⁴	Flame Spread ⁵	Smoke⁶	Toxicity⁷	Aging Effects
Air, 3/4"	0.87							Need citation, does not consider internal convection effects
Air Krete®²⁶ also see Concrete, Insulating, below	3.9	2.07 lbs/cuFt²⁶	0.1457 in/sec coefficient, or 0.3407 in/sec flow rate at 68 degF H2O²⁷		0²⁶	0²⁶	no	Cementious foam insulation, fireproof, non-toxic, non-shrinking, also used for acoustical sound proofing; MgO cement (Magnesium Oxide); 6 mil poly vapor barrier required

Balsam Wool insulation	2 - 3.5							Spills out of wall or roof insulation if facing is cut
Brick	0.2¹⁸							See Brick Nogging.
Brick facing, 1"	0.11							[Need citation]
Building paper, red rosin paper	0.06							[Need citation]
Cardboard as insulation	3 - 4²¹
Ceiling Panels, suspended or drop ceilings	0.4 - 6							varies widely by material See CEILINGS, DROP or SUSPENDED PANEL
Cellulose Insulation R-Values by type
Cellulose insulation loose fill	3.1 - 3.8^20,24	2.2-3.0	High	5-20%	15-40	0-45	CO	0-20% settlement, corrodes metal, mold resistant
Cellulose insulation, spray-on (wet spray)	2.8 - 3.5^20,24
Cementious Foam	0.35 - 0.69²¹
Cement asbestos wall shingles	0.03							[Need citation]

Concrete Insulating R-values by type
Concrete, uninsulated	0.08¹⁸ - 0.3125¹⁷							Typical residential weight concrete 8" wall = R 2.5
Concrete-insulated	0.85 - 1.2	12-88	Varies	Varies	0	0	0	Insulated forms available
Concrete, air entrained	3.90²¹
Air Krete®²⁶ also ThermalKrete and similar air-entraned MgO Products	3.90²⁶	2.07 lbs/cuFt²⁶	0.1457 in/sec coefficient, or 0.3407 in/sec flow rate at 68 degF H2O²⁷		0²⁶	0²⁶	no	Cementious foam insulation, fireproof, non-toxic, non-shrinking, also used for acoustical sound proofing; MgO cement (Magnesium Oxide); 6 mil poly vapor barrier required

Concrete block, 4-inch hollow core	1.11							[need citation]
Concrete block, 8-inch hollow core	1.70							[need citation]
Concrete block, 12-inch hollow core	1.90							[need citation]
Concrete block, lightweight 8-inch	2.2

Carpeting with fiber padding	2.08							[need citation]
Carpeting with foam padding	1.23							[need citation]
Cotton Insulation R-Values by type
Cotton insulation	0.5	.25-10
Cotton Batts	3.7²²							"blue jean" insulation batts fireproofed with boric acid

Dirt or Soil	0.25 - 1 0.80 typical at 20% moisture							Depends on soil properties: density, moisture content, moisture movement See R-Value of Earth
Drywall, 1/2-inch	0.45							[need citation]
Drywall, 3/4-inch	0.56							[need citation]
Fiberboard insulating boards	2.8							Questionable data, Some sources claim 2.64
Fibergoard nail base, 1/2-inch	1.14							Highly questionable [need citation]
Fiberglass Insulation R-Values by type
Fiberglass chopped, loose fill	2.5 - 3.7²⁰
Fiberglass chopped/blown insulation	3.6 - 4.4		100					6" = about R-22. Installers say expanding fiberglass assists in sealing air leaks
Fiberglass batt insulation	3.1 - 4.3²⁰	.6 - 1.2	100	1%	15-20	0-20	Fumes from paper, binders	May collect debris/allergens/mold Also see INSULATION CHOICES
Fiberglass, batts, hight density	3.6 - 5²¹
Fiberglass panel, rigid (fiberglass "boards")	2.5²¹							e.g. used in HVAC ductwork or air handlers.
Fiberglass, spray-on	3.7 - 2.9²⁰

Flooring, sheet resilient floors, linoleum, or tiles	0.05							[Need citation]

Glass	0.14¹⁸
Gypsum board	0.6							Drywall
Home®Foam²⁵ Spray or pour	3.9²¹	0.51 lbs/ft³						Insulthane 100, See Plastic, foamed insulation below Home Foam^? should not be installed within 2" / 50mm of heat emitting devices producing temperatures in excess of 200deg.
Icynene Foam Insulation R-Values
Icynene® Foam-poured insulation or pour fill insulation	4²³	.5-2 ¹⁰	low	low	low			Fire safety: may not be left exposed in living area; very good air bypass leak sealing properties
Icynene® Foam-sprayed insulation	3.6 - 3.7 ²³	.5-2 ¹⁰	low	low	low			Fire safety: may not be left exposed in living area; very good air bypass leak sealing properties

Mineral Wool insulation (Rock Wool)	3.2 - 3.7²⁰	1.5-2.5	100	2%	0	0	0	May collect debris/allergens/mold
Perlite insulation	2.5 - 3.7²⁰	2-11	High	0	0	0	0

Plywood, A/C	1.4							Questionable, [need citation]

Phenolic Foam Insulation R-Values
Phenolic foam spray insulation	4.8 - 7²¹
Phenolic foam insulation Phenolic rigid panel	8.3 4.4 - 8.2²⁰ 4 - 5²¹							Corrosion problems when in contact with steel roofing & moisture; very good air bypass leak sealing properties

Plaster, 1/2" lightweight	0.32							[Need citation]
Plastic, foamed: Home Foam²⁵ low-density	3.9²¹	0.51 lbs/ft³						Water-blown Unidentified ingredients ²⁵ Spray or pour application see HomeFoam® above.
Polyethylene foam	3²¹
Polyisocyanurate Foam Insulation R-Values
Polyisocyanurate spray, poured, or board insulation	4.3 - 8.3²¹ 5.5 - 6.2 to 7.04 - 8.0	2	2-3	0	25	55-200	CO	Closed cell, HCFC or CFC gases; 0-12% shrinkage, Fire safety: may not be left exposed in living area; thermal drift with aging; foil faced improves performance to R7-8.; very good air bypass leak sealing properties Also see INSULATION CHOICES
Polyisocyanurate foam board, foil faced	6.8²¹ - initial, pentane expanded 5.5²¹ - aged 5 to 10 years							Rigid panel insulation board with foil facing both sides, edges exposed
Polyisocyanurate composite insulation	2.8 (5.8-6.2)	2.0	2-3					Closed cell Foil faced²¹ See POLYISOCYANURATE FOAM INSULATION
Polystyrene Foam Insulation R-Values
Polystyrene peanuts for building insulation	not recom- mended				5-25+	10-400		Not recommended for building insulation, may be serious fires hazard.
Polystyrene loose fill beads for building or window-wall insulation	2.3				5-25+	10-400		Static charge makes particles hard to control
Polystyrene board or beadboard⁸ MEPS insulation molded EPS low density	3.6 - 5.0 3.85²¹	0.8-2.0	1.2-3.0	0.7-4%	5-25	10-400	CO	Degrades in sunlight (UV); R-value varies by board density Also see INSULATION CHOICES
Polystyrene Expanded (EPS) insulation low-density	3.85 3.9 - 4.4²⁰ 3.6 - 4.7²¹							See POLYSTYRENE FOAM INSULATION Also see INSULATION CHOICES
Polystyrene board, extruded expanded high-density (XPS) Molded	5 - 5.4²¹ 4.2²¹
Polystyrene board	5	1.5	1.2-3.0					Closed cell See POLYSTYRENE FOAM INSULATION
Polyisocyanurate / Polyurethane Foam Insulation R-Values
Polyisocyanurate / Polyurethane	5.6 - 7.0²⁰
Polyurethane spray - closed cell foam insulation. Thanks to Thanks to Andrew Cole for correcting our data on this product.	5.0 - 6.8 5.5 - 6.5²¹ Initial 7.14 Aged 6.8	2.0	2-3	0	30-50	155-200	CO	Closed cell; 0-12% shrinkage, Fire safety: may not be left exposed in living area. Initial R of 7.14 declines to 6.8 after several months of curing; very good air bypass leak sealing properties
Polyurethane foam insulation rigid panels	7-8²¹ - Initial 6.25 - aged 5 to 10 years							CHC/HCFC expanded foam
Polyurethane foam insulation rigid panels	6.8²¹ - Initial 5.5 - aged 5 to 10 years							Pentane expanded foam
Polyurethane spray insulation - open cell insulation	3.6²¹ - 7 (est)							Expands & seals more than closed-cell; lower cost; pourable-version available for building retrofit; See URETHANE FOAM Deterioration, Outgassing

Reflective insulation	2 - 17²⁰							Need details of products in this range
Rock Wool Batts Slag wool Batts	3 - 3.85²⁰							See Mineral Wool
Rock Wool, Slag wool Loose Fill insulation R-value	2.5 - 3.7²⁰
Roofing: Asphalt shingles	0.44
Roofing: built-up 3/8" thick plies	0.33
Roofing: wood shingles	0.94							[Need citation; wood shingles on walls - see below at "wood"]
Silica Aerogel	10
Snow	1
Straw Bale	1.45							STRAW BALE CONSTRUCTION
Stucco, conventional plaster/cement	0.20
Tectum™ insulated roof panels	2.0							Tectum: a patented cementitious wood fiber EPS-core insulating roof deck tile, plank, or panel of several thicknesses.
Thinsulate	5.75							Clothing insulation, not used in buildings
Vacuum Powder Insulation	25 - 30²⁰
Vacum powder insulated panels	20 - 100²⁰							U.S. DOE. Others cite R-30 - R-50.
Vermiculite insulation	2.13¹⁹- 3.0 2.10 - 3.7²⁰	4-10	High	0	0	0	0 (may contain asbestos)	May contain asbestos, virtually always installed as loose-fill. Some sources cite R=2.08
Urea Formaldehyde UFFI Foam Insulation R-Values & Properties
Urea Formaldehyde Foam Panels or in-wall spray	4 - 4.6²¹							Formaldehyde outgassing concerns, especially new, possibly
UFFI insulation (Urea Formaldehyde Foam)	4.2 5.25²¹	0.6-0.9	4.5-100	18%	0-25	0-30	0 (may outgas formal-dehyde)	1-4% shrinkage, Fire safety: may not be left exposed in living area; on aging, leaves significant air bypass leaks at shrinkage points
Wood, Hardwood, Softwood Insulation R-Values
Wood R-Values Log wall R-Values vary¹⁶	1.01 - 1.41 (softwoods) 0.71 (hardwoods)							The R-value of wood varies by wood density, species, moisture content.
Wood door, solid, per inch	1.56							Varies by species, no authoritative source.
Wood, soft	1.25							Questionable, [need citation]
Wood Flooring, assume 3/4" hardwood	0.68							[need citation]
Wood sheathing panels (Plywood,OSB)	2.5²¹							[need citation]
Wood shingle siding, single course	0.87							[need citation]
Wood siding, 1/2-inch clapboard or shiplap	0.81							[need citation]

Notes to the Table of Building Insulation Properties

R-Value is expressed as rate of heat loss per hour per square foot per inch of thickness of material per deg. F - see "R" value definition at Definitions of R K U values For some building materials (such as sheet flooring) we give an R-value for a specfic thickness other than the standard 1".
Insulation density is expressed in pounds per cubic foot of material
Permeability is expressed as the water vapor permeability of the material per inch of thickness. These numbers are most useful to compare one insulating material to another.
Absorption is the tendency of the insulation to absorb water in percent by weight. This is important for assessing the risk of mold in some materials
Flame Spread is a measure of fire resistance of the material. Use these numbers to compare one insulating material to another.
Smoke is a measure of fire safety - that is, the relative amount of smoke produced if the insulation is exposed to flame or combustion
Toxicity is a measure of fire safety - that is, toxins given off if the insulation is exposed to flame or combustion.
Polystyrene may be in molded or extruded forms and like some other plastic or foam insulations may be in open or closed cell form. (Closed cell foams are more moisture resistant). Polystyrene also is referred to as molded expanded polystyrene (MEPS), expanded polystyrene (EPS), and extruded polystyrene (XPS) - the most common foam board insulation product. MEPS & XPS are used in insulated structural panels and in insulating concrete forms (ICFs).
Links to details: Insulation product names in the first table column include links to articles that help identify and provide the properties of each insulating material listed.
Open vs. closed cell: Foam insulation densities vary among closed-cell vs open cell forms. Open cell foams are typically about 1/2 lb/cubic foot; Closed cell foams are more dense and rigid, typically about 2 lb/cu. ft.
C or Thermal conductance of these materials is the reciprocal of the R-value. C is known only when the k, the thermal conductivity of a material is known. k is the heat transmitted through a 1-inch thickness of homogenous material per square foot per hour when there is 1 degree of temperature change. k= (BTU * inch) / sq.ft. * hour * degF.
Air film: This table of R-values does not consider the insulating characteristic of the air film on each side of a surface nor the effects of wind on the air film or on the material itself. Some of these materials are more resistant to wind-caused heat transmission than others.
Moisture: Closed cell foams resist moisture uptake (good) but if construction is improper they can trap moisture (bad) leading to rot or mold problems in other building materials.
Insects: Exterior foam board on foundations can ease attack by wood destroying insects.
Fire & smoke: Foam insulation products present fire-smoke hazards and usually they must be protected with a fire barrier (usually 1/2" drywall).
R-Values for wooden log walls given by the U.S. DOE are in error except for square log walls. D-logs and round logs that are given a nominal log thickness, say 6" logs are calculated by DOE as having an R-value of just over 8. This is incorrect for non-square logs because the cross section of the log is 6" only at the log's widest point. A correct assessment of the R-value of a wooden log wall needs to be calculated based on the average wall thickness, considering the variation in thicknesses over the curvature of the logs. Therefore the DOE's value is on the "high" end of the R-value of a log wall.
R-Values of uninsulated concrete: Concrete Homes Magazine web search 5/18/2010
R-Value for concrete, glass, other materials, Wikipedia web search 5/18/2010 citing Ristinen, Robert A., and Jack J. Kraushaar. Energy and the Environment. 2nd ed. Hoboken, NJ: John Wiley & Sons, Inc., 2006.
E-Star Colorado. Energy Saving Calculations. Energy Living Alliance, 2008. Web 05/18/2010
U.S. Department of Energy, DOE Handbook, see http://buildingsdatabook.eren.doe.gov/TableView.aspx?table=5.1.3 18 May 2010. The DOE in turn cited these sources
- ASHRAE, 1997 ASHRAE Handbook: Fundamentals, p. 24-4, 22-5
- DOE, Insulation Fact Sheet, Jan. 1988, p. 6
- Journal of Thermal Insulation, 1987, p. 81-95
- ORNL, ORNL/SUB/88-SA835/1, 1990
- ORNL, Science and Technology for a Sustainable Energy Future, Mar. 1995, p. 17
- ORNL for vacuum insulation panel
Wikipedia, web search 5/18/2010 R-Values per Inch
EcoHaus UltraTouch cotton insulation batts batts http://www.ecohaus.com/C-121/ultratouch+batts Web search 5/18/2010
Icynene product information see http://www.icynene.com/icynene-insulation/ - Web search 5/18/2010
ICC Legacy Report ER-2833 - Cocoon Thermal and Sound Insulation Products, ICC Evaluation Services, Inc., Website: icc-es.org - Web search 5/18/2010
HomeFoam®, Home Insulation Corp. - see http://www.homefoam.ca/articles/Why_HF.htm - Web search 5/18/2010
Home Foam® does not contain formaldehyde, fibrous particulate, HFCs¹, CFCs² or HCFCs³ and is a zero-ODP⁴ product. The Saskatchewan Research Council (SRC) advises that even sensitive individuals may take occupancy just 24 hours after application is complete.
Air Krete®, Air Krete Inc., P.O. Box 380, Weedsport NY 13166-0380 Keene Christopher, Principal Telephone: (315) 834- 6609, Retrieved 05 Dec 2010, AirKrete® Green Insulation Specifications, original source: http://www.airkrete.com/ Specifications for AirKrete® can be found at http://www.airkrete.com/pdf/072101specification.pdf
AirKrete® Water Permeability Coefficient, 03/02/2005, letter provided by AirKrete, retrieved 05 Dec 2010, original source: http://www.airkrete.com/testResults_files/PermRating.pdf

Frequently Asked Questions (FAQs) about the R-values and insulating properties of various materials

Question: What is the R-value for earth, dirt, soil, backfill, or earth berms?

Sir: Does InspectApedia have an R-value for earth when used as a berm on an exterior concrete house wall? Thank you R.J.

Reply: Earth or soil has an R-value of about R 0.25 to R-1.0 per inch at 20% moisture content and other assumptions discussed here

But really, the insulating value of earth depends .... as we elaborate below. Also see "Dirt" in our table of insulating values shown just above

Sketch at left, courtesy of Carson Dunlop Associates, illustrates the effects of soil density and moisture as a source of pressure on a foundation wall.

As we note below, the R-value of the wet soil (sketch center) will be much lower than dry soil outside of the same volume of dry soil (sketch left). Freezing at the upper level of such wet soil also will affect its heat transfer rate as well as risking foundation damage as we show here.

A short answer to the R-Value of Dirt

Some sources we researched assert that "one inch of 'insulation' is equal to about two feet or more of soil. If we take 'insulation' to be a bit more specific, say the most commonly-used material, fiberglass, that's about R3 /inch for fiberglass, or if we believed the soil R-value rule of thumb about dirt, that's about 24/ 3 = about R 0.8 for arbitrary "dirt" insulation value.

R 0.8 sounds pretty reasonable if we assume about 20% moisture content, and if we consider for comparison or a "sanity check" that the R-value of uninsulated concrete is about R 0.8/inch.[1] Other engineering sources cite the R-value of earth as about R 0.25 per inch. Without normalizing for soil properties and moisture content, these numbers are very arm-waving rules of thumb.

But really this is in my opinion a very unreliable figure given the discussion below about the effects on heat transfer of soil properties and soil moisture. Heck even snow does better, at about R1/inch. In addition to avoiding the confusion that comes from an unreliable R-value for earth (take R 0.25 if you like), discussions of earth berm housing and underground housing usually consider the effects of thermal mass on building comfort, not just R-values.

R-values measure resistance to heat flow or transfer between materials. But thermal mass considers the storage effects of the mass of soil (or concrete block or ?) or other materials that comprise and surround a building. Thermal mass stores heat and returns it during cooler periods, evening out swings in building temperature. So let's keep in mind that while the R-value of two feet of soil outside of a building wall, say, may be R 0.5, that 24" of dirt has much greater thermal mass than the same quantity (in equivalent R-vale) of an insulating material such as fiberglass or solid foam insulation.

What all of this means is that it is a mistake to try to equate thermal mass and insulating values, and it makes no sense to forget about heat flow rates in or out of a structure if you are paying to heat or cool a building.

Details about the Insulating Properties of Dirt, Soil, Backfill, or Earth Berms

The R-value of earth depends on the type of soil and its water content. Even more significant can be the movement of groundwater through the surrounding soil, as moving water will significantly increase the rate of heat transfer from warm to cool areas.

At least important to anyone asking this question will be the assumptions about

The soil temperature Ts at some depth where it is stable (such as below the frost line in a freezing climate, perhaps as deep as 20 feet. A Journal of Light Construction online forum discussion of soil insulating properties includes the observation that

" [earth provides a ] huge amount of thermal mass, and that's what you'll be working with or fighting against. The soil temperature at about 20' is equal to the year round ambient temperature, so that will tell you what you'll be working with/against. If you want the room warmer or cooler than that, it's easier to install insulation and create a thermal mass inside that insulated envelope, if the ambient temperature is close to what you want, well, you don't need heat."[2]

For a more scholarly discussion of the insulating properties of soil you should consult a heat transfer engineer or a soils engineer. But here are my views of some important parameters to consider when assigning an insulating value to soil:

Soil temperature, or average soil temperature, or stable soil temperature at some pertinent depth, say below the frost line, below or around a structure, Ts.
Soil properties, such as average soil density and moisture levels and, as we cite above, the presence or absence of moving water through the soil
Target indoor temperature in the conditioned space, that is, the anticipated or target temperature of the indoor conditioned space, Ti
Building shell: the insulating value of the building shell or its resistance to heat flow from the warm to cool sides of the building exterior walls - R. Also, the air leakiness of compared building shells; an earth-bermed structure should leak less air than a similar structure whose exterior walls are exposed
Temperature differences: the difference between surrounding soils and the building interior, or slightly more formally, between Ts and Ti. If for a given climate those temperatures are close, then the heat flow into or out of the surrounding earth may be slow enough to give a workable design. If the difference between those two is great, then in my OPINION, a building design would be wise to include building shell insulation of sufficient R-vale. The temperature difference between conditioned and unconditioned space is in my opinion a most critical figure since the larger that difference (delta T) the faster heat will flow from warm to cool materials.

Material I've reviewed about earth sheltered homes and schemes that use electric radiant heated floors over uninsulated soil (where electricity is dirt cheap), but I'd prefer to evaluate that "design" with comments by heat transfer experts since it seems to me that any system that pumps heat into uninsulated ground in a cold climate is spending a significant portion of their heating dollar to return heat to Mother Earth rather than to Mommy upstairs.

The claim that "heat you pump into the ground under or around a home doesn't really go anywhere" is in violation of the basic laws of thermodynamics and is simply not so. Heat flows from warmer to cooler materials. Sure we can expect there to be a temperature gradient in cool soil beneath or against a heated building, but heat flows from warmer to cooler materials, it doesn't magically stop dead at some arbitrary distance. Just where energy costs are very low and are expected to stay low might it sound plausible to use uninsulated earth for heat storage under or around a building.

References for the insulating properties of soil or dirt or earth

[1] Building Envelope, Basement, Kansas State University engineering extension, Energy Extension Service, KSU Engineering Extension 133 Ward Hall Manhattan, KS 66506 Phone: 785.532.6026 Fax: 785.532.6952, web search 08/16/11, original source: www.engext.ksu.edu/ees/henergy/envelope/basement.html
[2] "R-value of Dirt", Journal of Light Construction Forum, archive, web search 08/16/11, original source: forums.jlconline.com/forums/archive/index.php/t-42036.html
[3] National Research Council, Canada, NRC Institute for Research in Construction, web search 08/16/11, original source: http://irc.nrc-cnrc.gc.ca/fulltext/nrcc43093/
[4] Hait, John, Passive Annual Heat Storage (PAHS), Rocky Mountain Research Center; 1st ed(1983), ISBN-10: 0915207001 ISBN-13: 978-0915207008 "Passive annual heat storage: Improving the design of earth shelters, or, How to store summer's sunshine to keep your wigwam warm all winter "
[5] Hait, John, Passive Annual Heat Storage: Improving the Design of Earth Shelters, quoting Amazon review: a unique approach to using the earth as a low cost heat storage media which surrounds one's house. Technically accurate and from this physicists point of view a correct assessment of the laws of nature involved and how to use them to our advantage.
[6] Hait, John, RMRC earth sheltered vaulted-roof modular building system, Rocky Mountain Research Center (1989), ASIN: B000736VRG
[7] "Earth Thermal Storage Systems, [radiant floor heating], ", Therma-Ray Inc. 670 Wilsey Road, Unit 6 Fredericton, New Brunswick Canada E3B 7K4 Tel: 866-457-4600 (toll free) or 506-457-4600 Email: info@thermaray.com Web: web search 08/16/11, original source: http://www.thermaray.com/solutions/earth.html
[8] CanGEA Canadian Geothermal Energy Association, PO Box 1462 Station M Calgary, Alberta, Canada T2P 2L6 Tel:(403) 801 6805 Email: info@cangea.ca web search 08/16/11, original source: http://www.cangea.ca/
[9] RADIANT HEAT MISTAKES illustrates a horrible radiant floor installation that couldn't overcome heat losses through soils & possibly also through the foundation perimeter - a Northern Minnesota fiasco at which the builder insisted that "once you heat up the soil under that floor it'll just keep you warm all winter" - boy was he wrong.

Question: more on the R-value of soil or dirt

hello, just noticed that your insulation value for dirt is inaccurate. if you are saying that 24inches of earth insulates the same as 1 inch of fiberglass, or R3, than that means 8 inches of dirt has R1, or that an inch of dirt is R 0.125. Am i wrong? Cheers, - G.R. 2/29/2013

Reply:

In this article, just above, we include a longer discussion of this question about the insulating properties of soil or dirt.

In fact there is no single right soil R-value answer without considering soil moisture levels and soil density, particle composition, but our research did find some interesting scholarly articles that gave a range of values. Above we give quite a few source citations on this topic.

In sum, if you like a dir R-value of R=0.25 per inch of soil, then 24-inches of dirt at that R-value and moisture assumptions would be about (0.25 x 24 = 6) or R-6.

...

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Technical Reviewers & References

Related Topics, found near the top of this page suggest articles closely related to this one.

Thanks to Andrew Cole, FOAM FACTOR, a Canadian based installer of 2lb. Closed Cell foam. Mr. Cole informs us that they only work with this material. "We feel that the superior performance characteristics make it a far superior choice in building envelopes of all types. Our material of choice now is POLARFOAM 7300-0 SOYA which is manufactured by DEMILEC here in Canada." Mr. Cole can be contacted at 905-271-6644 or at acole@bestsprayfoam.com - 04/30/2009.
Carson, Dunlop & Associates Ltd., 120 Carlton Street Suite 407, Toronto ON M5A 4K2. (416) 964-9415 1-800-268-7070 info@carsondunlop.com. The firm provides professional home inspection services & home inspection education & publications. Alan Carson is a past president of ASHI, the American Society of Home Inspectors. Thanks to Alan Carson and Bob Dunlop, for permission for InspectAPedia to use text excerpts from The Home Reference Book & illustrations from The Illustrated Home. Carson Dunlop Associates' provides:
- Commercial Building Inspection Courses - protocol ASTM Standard E 2018-08 for Property Condition Assessments
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  Special Offer: For a 10% discount on any number of copies of the Home Reference Book purchased as a single order. Enter INSPECTAHRB in the order payment page "Promo/Redemption" space. InspectAPedia.com editor Daniel Friedman is a contributing author.
- The Home Reference eBook, an electronic version for PCs, the iPad, iPhone, & Android smart phones.
  Special Offer: For a 5% discount on any number of copies of the Home Reference eBook purchased as a single order. Enter inspectaehrb in the order payment page "Promo/Redemption" space.
- The Illustrated Home illustrates construction details and building components, a reference for owners & inspectors.
  Special Offer: For a 5% discount on any number of copies of the Illustrated Home purchased as a single order Enter INSPECTAILL in the order payment page "Promo/Redemption" space.
- The Horizon Software System manages business operations,scheduling, & inspection report writing using Carson Dunlop's knowledge base & color images. The Horizon system runs on always-available cloud-based software for office computers, laptops, tablets, iPad, Android, & other smartphones.
Asbestos pipe insulation in buildings
Brick "Insulation" in Building Walls
HEAT LOSS CALCULATIONS, Insulation Properties, Definitions of R, K, U values, Insulation Design
How to Choose an Air Conditioner - BTU Chart
How to Detect and Correct Attic Condensation & Prevent Ice Dam Leaks in buildings
How to Inspect Building Interiors and Building Insulation/Ventilation list of articles about building insulation inspection, defects, design, and ventilation requirements
Indoor Air Quality Investigations: Fiberglass in Indoor Air, HVAC ducts, and Building Insulation
Insulation Identification Photographs - Cellulose insulation photos, Mineral wool insulation photos, rock wool insulation photos, cotton insulation photos, balsam wool insulation photos
Insulation Identification Photographs - Vermiculite insulation photos
Insulation Materials as Indicators of Building Age
Insulation Properties, Table of R-Values, density, moisture permeability, fire safety, aging effects on various insulation materials
Insulation Types, table of common building insulation properties from U.S. DOE.
"Insulation: Adding Insulation to an Existing Home," U.S. Department of Energy - tips on how to do your own check for the presence of absence of insulation in a home
LP or Natural Gas Pressures & BTUH per Cubic Foot
Mold in Fiberglass in Insulation
Radiant Heat Floor Mistakes to Avoid
Rated Cooling Capacity - How to Determine Air Conditioning Equipment Rated Cooling Capacity
Un-Vented Roof Solutions - How to Prevent Attic Condensation, Ice Dam Leaks, Roof Mold, & Roof Structural Damage in buildings with Un-vented Roof Cavities
Vermiculite Building Insulation & Asbestos
Brick nogging used as soundproofing is mentioned in this article on Popular Forest
Brick Nogging, Historical Investigation and Contemporary Repair, Construction Specifier, April 2006. Historical use of brick in timber-framed buildings, drawing on the investigations of the Kent Tavern in Calais, VT. "Brick nogging is a European method of construction which was brought to the new world in the early-nineteenth century. It was a common construction method that employed masonry as infill between the vertical uprights of wood framing." -- quoting the web article review.
Photo of very rough in-wall brick nogging at an architects website
Building Research Council, BRC, nee Small Homes Council, SHC, School of Architecture, University of Illinois at Urbana-Champaign, brc.arch.uiuc.edu. "The Small Homes Council (our original name) was organized in 1944 during the war at the request of the President of the University of Illinois to consider the role of the university in meeting the demand for housing in the United States. Soldiers would be coming home after the war and would be needing good low-cost housing. ... In 1993, the Council became part of the School of Architecture, and since then has been known as the School of Architecture-Building Research Council. ... The Council's researchers answered many critical questions that would affect the quality of the nation's housing stock.
- How could homes be designed and built more efficiently?
- What kinds of construction and production techniques worked well and which did not?
- How did people use different kinds of spaces in their homes?
- What roles did community planning, zoning, and interior design play in how neighborhoods worked
"Energy Savers: Whole-House Supply Ventilation Systems [copy on file as /interiors/Energy_Savers_Whole-House_Supply_Vent.pdf ] - ", U.S. Department of Energy energysavers.gov/your_home/insulation_airsealing/index.cfm/mytopic=11880?print
"Energy Savers: Whole-House Exhaust Ventilation Systems [copy on file as /interiors/Energy_Savers_Whole-House_Exhaust.pdf ] - ", U.S. Department of Energy energysavers.gov/your_home/insulation_airsealing/index.cfm/mytopic=11870
"Energy Savers: Ventilation [copy on file as /interiors/Energy_Savers_Ventilation.pdf ] - ", U.S. Department of Energy
"Energy Savers: Natural Ventilation [copy on file as /interiors/Energy_Savers_Natural_Ventilation.pdf ] - ", U.S. Department of Energy
"Energy Savers: Energy Recovery Ventilation Systems [copy on file as /interiors/Energy_Savers_Energy_Recovery_Venting.pdf ] - ", U.S. Department of Energy energysavers.gov/your_home/insulation_airsealing/index.cfm/mytopic=11900
"Energy Savers: Detecting Air Leaks [copy on file as /interiors/Energy_Savers_Detect_Air_Leaks.pdf ] - ", U.S. Department of Energy
"Energy Savers: Air Sealing [copy on file as /interiors/Energy_Savers_Air_Sealing_1.pdf ] - ", U.S. Department of Energy
Fiberglass: Indoor Air Quality Investigations: Health Concerns About Airborne Fiberglass: Fiberglass in Indoor Air from HVAC ducts, and Building Insulation

Books & Articles on Building & Environmental Inspection, Testing, Diagnosis, & Repair

Our recommended books about building & mechanical systems design, inspection, problem diagnosis, and repair, and about indoor environment and IAQ testing, diagnosis, and cleanup are at the InspectAPedia Bookstore. Also see our Book Reviews - InspectAPedia.

The Home Reference Book - the Encyclopedia of Homes, Carson Dunlop & Associates, Toronto, Ontario, 25th Ed., 2012, is a bound volume of more than 450 illustrated pages that assist home inspectors and home owners in the inspection and detection of problems on buildings. The text is intended as a reference guide to help building owners operate and maintain their home effectively. Field inspection worksheets are included at the back of the volume. Special Offer: For a 10% discount on any number of copies of the Home Reference Book purchased as a single order. Enter INSPECTAHRB in the order payment page "Promo/Redemption" space. InspectAPedia.com editor Daniel Friedman is a contributing author.

Or choose the The Home Reference eBook for PCs, Macs, Kindle, iPad, iPhone, or Android Smart Phones. Special Offer: For a 5% discount on any number of copies of the Home Reference eBook purchased as a single order. Enter INSPECTAEHRB in the order payment page "Promo/Redemption" space.

American Plywood Association, APA, "Portland Manufacturing Company, No. 1, a series of monographs on the history of plywood manufacturing",Plywood Pioneers Association, 31 March, 1967, www.apawood.org
Asbestos: How to find and recognize asbestos in buildings - visual inspection methods, list of common asbestos-containing materials
Asbestos HVAC Ducts and Flues field identification photos and guide
Asbestos products and their history and use in various building materials such as asphalt and vinyl flooring includes discussion which draws on Asbestos, Its Industrial Applications, D.V. Rosato, engineering consultant, Newton, MA, Reinhold Publishing, 1959 Library of Congress Catalog Card No.: 59-12535 (out of print).
Asbestos Identification and Testing References

Asbestos Identification, Walter C.McCrone, McCrone Research Institute, Chicago, IL.1987 ISBN 0-904962-11-3. Dr. McCrone literally "wrote the book" on asbestos identification procedures which formed the basis for current work by asbestos identification laboratories.
Stanton, .F., et al., National Bureau of Standards Special Publication 506: 143-151
Pott, F., Staub-Reinhalf Luft 38, 486-490 (1978) cited by McCrone

Humidity: What indoor humidity should we maintain in order to avoid a mold problem?
Nogging: See this photo of exposed bricks on a building exterior on a building exterior in Canada. [Thanks to Carson Dunlop, Toronto - see References below].
Piquet Wall Construction: See this photo of piquet wall construction - involving timber-framed wall construction with long top girts, diagonal timber bracing, and small diameter logs placed vertically along with concrete chinking to fill in the wall plane.
Plank House Construction: weblog from plankhouse.wordpress.com/2009/01/25/plank-house-construction/ and where plank houses were built by native Americans, see
Large 1:6 Scale Plank House Construction / P8094228, Photographer: Mike Meuser
06/12/2007 documented at yurokplankhouse.com where scale model Museum quality Yurok Plank Houses are being sold to raise money for the Blue Creek - Ah Pah Traditional Yurok Village project.
Rubblestone Wall Filler: See this Lartigue House using exterior-exposed rubblestone filler between vertical timbers of a post and beam-framed Canadian building.
"Weather-Resistive Barriers [copy on file as /interiors/Weather_Resistant_Barriers_DOE.pdf ] - ", how to select and install housewrap and other types of weather resistive barriers, U.S. DOE
Weaver: Beaver Board and Upson Board: Beaver Board and Upson Board: History and Conservation of Early Wallboard, Shelby Weaver, APT Bulletin, Vol. 28, No. 2/3 (1997), pp. 71-78, Association for Preservation Technology International (APT), available online at JSTOR.
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	Free Encyclopedia of Building & Environmental Inspection, Testing, Diagnosis, Repair	Ask a Question or Search InspectAPedia

Free Encyclopedia of Building & Environmental Inspection, Testing, Diagnosis, Repair

Ask a Question or Search InspectAPedia

Table of Characteristics of Various Insulating Materials: fiberglass, mineral wool, cellulose, foam insulating board, UFFI, vermiculite, others

Cellulose Insulation R-Values by type

Concrete Insulating R-values by type

Cotton Insulation R-Values by type

Fiberglass Insulation R-Values by type

Icynene Foam Insulation R-Values

Phenolic Foam Insulation R-Values

Polyisocyanurate Foam Insulation R-Values

Polystyrene Foam Insulation R-Values

Polyisocyanurate / Polyurethane Foam Insulation R-Values

Urea Formaldehyde UFFI Foam Insulation R-Values & Properties

Wood, Hardwood, Softwood Insulation R-Values