Insulation R values of various materials:
Here we provide extensive Tables of Insulation Values and Properties for Various Insulation & Building Materials or other substances useful in procedures to measure or calculate heat loss in a building.
Page top photo by the author, the Formula-R and Owens Corning markings, 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.
InspectAPedia tolerates no conflicts of interest. We have no relationship with advertisers, products, or services discussed at this website.
- Daniel Friedman, Editor/Publisher - See WHO ARE WE?
These tables give R-values of all sorts of materials, in alphabetical order with direct links to some popular insulating materials.
They also give the insulating value of any material of interest in construction, for example: air, fiberglass, masonry mateirals, mineral wool, cellulose, foam insulating board, UFFI, soil or dirt, vermiculite, wood, & most other building materials.
Here we provide first an alphabetic index to the insulating or R-values of all sorts of building materials, even substances like air and dirt.
Photo: yellow fiberglass insulating batts in a sloppy insulation installation job.
A - B - C - D - E - F - G - H - I - J - K - L - M - N - O - P - Q - R - S - T - U - V - W - X - Y - Z
Below we also give links to skip directly to popular insulation materials or just skip directly to the start of the COMPLETE INSULATION DATA TABLE where you will find that we list all building materials and insulating materials in alphabetic order.
Nearly all building materials are found there as well as the insulating properties of other materials of interest.
Tip: Also use the page top Search box to look for our articles about specific insulating materials and their properties.
We also provide conversion values & formulas to convert between U.S., Metric, & Imperial system measures of insulating value or heat loss value.
Quick Links to Often Requested Material Insulating Properties |
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AIR SPACES | PLASTER |
ASBESTOS | PLYWOOD & OSB |
BALSAM WOOL | POLYCARBONATE films |
BRICK | POLYISOCYANURATE foam |
CELLULOSE | POLYSTYRENE foam |
CONCRETE | POLYURETHANE foam |
COTTON | REFLECTIVE barriers |
DRYWALL | ROCK WOOL mineral wool |
FIBERBOARD | ROOFING materials |
FIBERGLASS | SIDING MATERIALS |
FOAM INSULATION Icynene, Phenolic | SNOW |
GLASS & INSULATED GLASS | SOIL - dirt |
ICYNENE foam | UFFI Foam |
MASONRY brick, block, concrete | VACUUM insulating panels |
MINERAL WOOL | VERMICULITE insulation |
PERLITE | WINDOWS & glazing & insulating shades |
PHENOLIC spray foam | WOOD materials |
In general all of the measures of heat-loss or heat-gain insulating properties of materials are measuring the rate at which heat flows through a material.
The "R" value of a material is the material's resistance to heat flow through the material, but different countries or areas of the world use and compute these values differently.
Generally there are three different R-Values:
To convert among R and U values in these different systems:
Also
See details at HEAT LOSS R U & K VALUE CALCULATION where we explain how to calculate or convert between R-value, U-value, and K-value of materials.
Tables of Insulation & Other Building Material Properties - Alphabetical OrderAcrylic to Asbestos |
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Insulation or other Building Material 9 |
R-ValueUSA1 |
RSI 1 | Density2 | Perm3 | Absorption4 | Flame Spread 5 |
Smoke6 | Toxicity7 | Aging Effects & Comments |
Acrylic twin-wall greenhouse glazing |
1.82 32 -U.S. |
0.3276 |
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Aerogel | 10.3 / Inch |
1.854 | See AEROGEL INSULATION | ||||||
Air gap or air film, 3/4" air space insulating properties | 0.87 / inch
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0.1566
|
The R=0.87 value for the first value in this Air R-value table subsection: For a 3/4" air gap or air space 30 Heat flow direction: up, one reflective surface, R=2.22 (Summer) or R=2.21 (Winter) Also see REFLECTIVE barriers Heat flow direction: down, no reflective surfaces, R=0.85 (Summer) or R=1.02 (Winter) Heat flow direction: down, one reflective surface, R=3.29 (Summer) or R=3.59 (Winter) Heat flow direction: horizontal, no reflective surfce, R= 0.84 (Summer) or R=1.01 (Winter) Heat flow direction: horizontal, one reflective surface, |
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Air film, inside surface, still air, no reflective surface, directions vary: horizontal, vertical, up, or down | 0.6140 - 0.92 0.1098 - 0.1656 |
0.11 - 0.17 0.02- 0.03 |
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Air film, inside surface, still air, + reflective surface or barrier, directions vary: horizontal, vertical, up, or down | 1.32 - 4.55 30 | 0.24 - 0.82 | |||||||
Air film, outside surface, any direction, any position, 15 mph wind in winter | 0.17 30 | 0.03 | |||||||
Air film, outside surface, any direction, any position, 7.5 mph wind in summer |
0.25 30 |
0.05 | |||||||
Air, exterior film on walls | 0.17 30,40 | 0.03 | Presumes no wind or air movement? | ||||||
Air, interior film on walls | 0.6840 | 0.12 | Presumes no air movement? | ||||||
Dead air space in wall cavity, 3/4" to 4" (winter) | 0.97 | .17 | Presumes no convection air movement? Convection movements reducing R-values are more likely in wider dead air spaces and are virtually certain if there are leaks or penetrations at wall top and bottom. |
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Dead air space 1/2" to 4" | 1.0040 | 0.18 | 1.0040 total thickness Note "Dead" air space; convection currents in cavities or along surfaces lose insulating value. |
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Air Krete®26 |
3.9 | 0.70 | 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 |
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Aluminum siding | 0.6140 metal thickness |
0.11 | 0.6140 full thickness, hollow-backed | ||||||
Asbestos, corrugated paper pipe insulation | 1.4 | 0.25 | Estimated R-value of asbestos insulation per inch for pipe insulation corrugated paper. Asbestos lagging and paste will have a lower value |
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Asbestos cement board R-value | 0.25 | 0.45 | www.msu.edu
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Asbestos loose packed fibers / powder | Thermal conductivity k = 0.15 | ||||||||
Asbestos cement shingle siding | 0.03 | 0.005 | [30] |
Insulation Values Table Continued: Balsam Wool to Building Paper |
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Insulation or other Building Material 9 |
R-Value1 | RSI | Density2 | Perm3 | Absorption4 | Flame Spread 5 |
Smoke6 | Toxicity7 | Aging Effects & Comments |
Balsam Wool insulation | 2 - 3.5 | 0.36 - 0.63 | Spills out of wall or roof insulation if facing is cut | ||||||
Brick, common | 0.218 30 | 0.36 | See BRICK WALL INSULATION RETROFIT [30] |
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Brick facing, 1" | 0.11 | 0.02 | [Need citation] | ||||||
More Brick values - see Masonry at - M - | |||||||||
Bubble Foil Sheets | 1.1 - 1.3 / layer 4.4 / inch |
0.20 - 0.23 0.79 |
BUBBLE / CLOSED-CELL FOAM SHEETS | ||||||
Building Paper, asphalt impregnated felt, 15# permeable | 0.06 | 0.01 | [30] | ||||||
Building paper, red rosin paper | 0.06 | 0.01 | [Need citation] |
Cardboard, Ceiling Panels, Cellulose Insulation R-Values by type |
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Insulation or other Building Material 9 |
R-Value1 | RSI | Density2 | Perm3 | Absorption4 | Flame Spread 5 |
Smoke6 | Toxicity7 | Aging Effects & Comments |
Cardboard as insulation | 3 - 421 | 0.54 - 0.72 | |||||||
Ceiling Panels, suspended or drop ceilings | 0.4 - 6 | 0.07 - 1.08 | varies widely by material |
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Cellulose Blown (Attic) | 3.1340 | 0.56 | |||||||
Cellulose Blown (Wall) | 3.7040 | 0.67 | |||||||
Cellulose insulation loose fill | 3.1 - 3.820,24 | 0.56 - 0.68 | 2.2-3.0 | High | 5-20% | 15-40 | 0-45 | CO | 0-20% settlement, corrodes metal, mold resistant Or R 3.13 - 3.7030 |
Cellulose insulation, spray-on (wet spray) | 2.8 - 3.520, 24 | 0.50 - 0.63 |
Concrete Insulating R-values by type (Also see "Masonry Materials R-Values" below) |
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Insulation or other Building Material 9 |
R-Value1 | RSI | Density2 | Perm3 | Absorption4 | Flame Spread 5 |
Smoke6 | Toxicity7 | Aging Effects & Comments |
Cementious Foam | 0.35 - 0.6921 | 0.63 - 0.12 | |||||||
Cement asbestos wall shingles | 0.03 | 0.005 | [Need citation] |
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Concrete, air entrained | 3.9021, 40 | 0.70 | |||||||
Air Krete®26 also ThermalKrete and similar air-entraned MgO Products |
3.9026 | 0.70 | 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 |
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Concrete, uninsulated | 0.0818 30 - 0.312517 0.52 |
0.01 - 0.06 | Typical residential weight concrete 8" wall = R 2.5 | ||||||
Concrete, sand & gravel aggregate | 0.13 - 0.6430 | 0.02 - 0.12 | 8" thick concrete slab or foundation wall has an R-value of about 1.04 30 while lightweight aggregate filled 8" thick concrete has an R-value of about 2.18 30 | ||||||
Concrete-insulated | 0.85 - 1.2 | 0.15 - 0.22 | 12-88 | Varies | Varies | 0 | 0 | 0 | Insulated forms available |
Concrete block, hollow core |
4" - 0.80 8" - 1.11 12" - 1.28 |
Without addition of insulation inserts into the block. |
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Concrete block, 4-inch hollow core | 1.11 A | 0.20 | See citations at "Masonry" below | ||||||
Concrete block, 8-inch hollow core | 1.04 - 2.18, commonly 1.04 30 | 0.18 - 0.39 | [30] | ||||||
Concrete block, 12-inch hollow core | 1.90 | 0.34 | [need citation] | ||||||
Concrete block, lightweight 8-inch | 2.2 | 0.40 | lightweight concrete | ||||||
Concrete block, hollow cores grouted with concrete | 0.19 | elminination of the hollow core air space conducts more heat | |||||||
Concrete block, hollow cores grouted with insulating material | Note A | See CONCRETE BLOCK INSULATION | |||||||
More concrete values see Masonry at - M - | |||||||||
Carpeting with fiber padding | 2.0830 | 0.37 | |||||||
Carpeting with foam padding |
1.2330 | 0.22 | Typical low-pile carpeting with foam or rubber carpet padding |
Cotton Insulation R-Values by type |
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Insulation or other Building Material 9 |
R-Value1 | RSI | Density2 | Perm3 | Absorption4 | Flame Spread 5 |
Smoke6 | Toxicity7 | Aging Effects & Comments |
COTTON INSULATION |
0.5 | 0.09 | .25-10 | ||||||
Cotton Batts | 3.722 | 0.67 | "blue jean" insulation batts fireproofed with boric acid BORIC ACID MSDS (Fisher Scientific 2014) |
Dirt, Backfill, Soil R-Values |
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Insulation or other Building Material 9 |
R-Value1 | RSI | Density2 | Perm3 | Absorption4 | Flame Spread 5 |
Smoke6 | Toxicity7 | Aging Effects & Comments |
DIRT or SOIL | 0.25 - 1 0.80 typical at 20% moisture |
0.45 - 0.18 | Depends on soil properties: density, moisture content, moisture movement See SOIL R-VALUES Note: soil often contains water that has its own R of around 0.004 |
...
Drywall or Gypsum Board or "Sheetrock" R-Values |
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Insulation or other Building Material 9 |
R-Value1 | RSI | Density2 | Perm3 | Absorption4 | Flame Spread 5 |
Smoke6 | Toxicity7 | Aging Effects & Drywall, 1/2-inch |
0.45 |
0.08 |
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(McCullough 2011) [37] (Humberto 2018) [38] - [39] [Other citations welcomed]Drywall, 3/4-inch |
0.56 |
0.10 |
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Gypsum board Insulating Value |
0.6 |
0.11 |
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Drywall 1/2" Gypsumboard = R 0.45 30 5/8" Gypsum board = R 0.56 30 See DRYWALL R-Values |
...
Insulation Values Table Continued: Fiberboard Products |
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Insulation or other Building Material 9 |
R-Value1 | RSI | Density2 | Perm3 | Absorption4 | Flame Spread 5 |
Smoke6 | Toxicity7 | Aging Effects & Comments |
Fiberboard insulating boards - per inch | 2.8 30 | 0.50 | Questionable data, Some sources claim 2.64 | ||||||
Fiberboard 1/2" intermediate density, per inch | 2.44 30 | 0.44 | 1.32 40 full thickness Questionable; [30] Divide this per inch number by 2 to obtain the R-value for 1/2" medium density fiberboard = R 1.22 |
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Fiberboard 25/32" | 2.06 40 full thickness | ||||||||
Fiberboard insulating sheathing, regular density, per inch | 2.64 30 | 0.48 | Questionable; [30] Divide this per inch number by 2 to obtain the R-value for 1/2" regular density fiberboard = R 1.32 | ||||||
Fiberboard insulating sheathing, 25/32" thick, regular density, per inch | 2.64 30 | 0.48 | Questionable; [30] |
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Fiberboard nail base insulating board, 1/2-inch | 1.14 30 | 0.21 | Highly questionable [30] Also see HARDBOARD R-VALUES |
Insulation Values Table Continued: Fiberglass to Flooring |
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Insulation or other Building Material 9 |
R-Value1 | RSI | Density2 | Perm3 | Absorption4 | Flame Spread 5 |
Smoke6 | Toxicity7 | Aging Effects & Comments |
Fiberglass Insulation R-Values by type |
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Fiberglass, Blown (Attic) | 2.2040 | 0.40 | |||||||
Fiberglass, Blown (Wall) | 3.2040 | 0.58 | |||||||
Fiberglass chopped, loose fill | 2.5 - 3.720 | 0.45 - 0.67 | |||||||
Fiberglass chopped/blown insulation | 3.6 - 4.4 | 0.65 - 0.79 | 100 | 6" = about R-22. Installers say expanding fiberglass assists in sealing air leaks | |||||
FIBERGLASS BATT insulation | 3.1 - 4.320 | 0.56 - 0.77 | .6 - 1.2 | 100 | 1% | 15-20 | 0-20 | Fumes from paper, binders |
May collect debris/allergens/mold 3-3 1/2" thick fiberglass insulation = R 11 |
Fiberglass, batts, high density | 3.6 - 521 |
0.65 - 0.90 | |||||||
Fiberglass 3/4" | 3.0 | 0.54 | 3.00 40 full thickness | ||||||
Fiberglass 1" | 4.0 | 0.72 | 4.00 40 full thickness | ||||||
Fiberglass 1 1/2" | 6.0 | 1.08 | 6.00 40 full thickness | ||||||
Fiberglass, Rigid | 4.0040 | 0.72 | (<4 lb/ft3) | ||||||
Fiberglass glazing (greenhouse) | 0.83 32 - single | 0.15 | |||||||
Fiberglass panel, rigid (fiberglass "boards") | 2.521 | 0.45 | e.g. used in HVAC ductwork or air handlers. | ||||||
Fiberglass, spray-on | 3.7 - 2.920 | 0.67 - 0.52 | |||||||
Flooring Insulationg Value |
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Flooring, hardwood, 3/4" thick, per inch: | 1.10 | 0.2 | 3/4" hardwood flooring = R 0.68 30 presuming no air leakage | ||||||
Flooring, sheet resilient floors, linoleum, or tiles | 0.0530 | 0.009 | Applies to Asphalt/asbestos floor tiles, linoleum, vinyl, rubber floor tiles, per inch. |
Insulation Values Table Continues: Glass to Gypsum Board |
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Insulation or other Building Material 9 |
R-Value1 | RSI | Density2 | Perm3 | Absorption4 | Flame Spread 5 |
Smoke6 | Toxicity7 | Aging Effects & Comments |
Glass single glazing
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0.1418
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0.025 | U-Values for Glass & Glazing 30Single pane glass, Winter U = 1.10 30
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Double glazed glass Note the U-values in Comments |
2.0 32 2.5 (low-E) |
0.36 0.45 |
Insulated Glass, double pane U=Values 303/16" Air Space, Winter U = 0.62 30 |
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Glass, triple-glazed | 2.27 - 3.22 | 0.41 - 0.58 | U Value, Winter 0.31-0.39 30 R = 1 / U U 1 = R 1 the R-values given at left are questionable. |
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Glass Storm Windows, 1 - 4" space between storm interior surface & interior window exterior surface | 0.50 30 | 0.090 | Highly questionable without assessment of the leakiness of the storm window and also of the leakiness of the principal window sash. | ||||||
Also see glass insulating values discussed at WINDOWS & glazing & insulating shades | |||||||||
Gypsum board Insulating Value | 0.6 | 0.11 | 1/2" Gypsumboard = R 0.45 30 5/8" Gypsum board = R 0.56 30 See DRYWALL R-Values |
Insulation Values Table Continued: Hardboard to Insulating Board Products |
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Insulation or other Building Material 9 |
R-Value1 | RSI | Density2 | Perm3 | Absorption4 | Flame Spread 5 |
Smoke6 | Toxicity7 | Aging Effects & Comments |
Hardboard siding 1/2" | 0.34 | 0.061 | 0.3440 full thickness | ||||||
Hardboard, high density, standard tempered 1/4" thick, Per Inch | 1 30 | 0.180 | 1/4" thick hardboard, high-density = R 0.25 [30] Note that many builders refer to this wood product hardboard by a specific trade name "Masonite™" or "Masonite hardboard" |
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Hardboard underlayment, 1/4", per inch: | 1.24 30 | 0.22 | 1/4" thick hardboard underlayment = R 0.31 [30] | ||||||
Home®Foam25 Spray or pour |
3.921 | 0.70 | 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. |
Insulating Board R-Values |
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Insulation or other Building Material 9 |
R-Value1 | RSI | Density2 | Perm3 | Absorption4 | Flame Spread 5 |
Smoke6 | Toxicity7 | Aging Effects & Comments |
Insulating board, glass fiber organic bonded | 4.00 30 | 0.72 | |||||||
Insulating board, expanded ploystyrene, extruded, cut cell | 4.00 30 | 0.72 | |||||||
Insulating board, expanded polystyrene extruded smooth | 5.00 30 | 0.90 | |||||||
Insulating board, expanded polystyrene molded bead panel | 3.57 30 | 0.64 | See POLYSTYRENE foam |
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Insulating board, expanded polyurethane | 6.25 30 | 1.125 | See POLYURETHANE foam |
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Insulating board, polyisocyanurate foam | 7.20 - 8.0 30 | 1.296 - 1.44 | See POLYISOCYANURATE foam |
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Insulating board, mineral fiber, resin binder | 3.45 30 | 0.621 | |||||||
Nail Base Insulated Panels R value | 4.2 - 5.3 LTTR 1 | 0.756 - 0.954 | Plywood or OSB laminated with rigid foam board insulation 1 |
1. LTTR = Long Term thermal resistance, for panels ranging from 1.5" (LTTR 6.3) to 4.5" (LTTR 24.2) in thickness, OSB laminated to closed-cell polyisocyanurate foam board insulation, OSB on one side, used as roofing nail base, Source: Atlas Roof Wall Insulation, 2000 RiverEdge Parkway, Suite 800 Atlanta, GA 30328 USA Website: https://roof.atlasrwi.com 2020/11/08
Definition: LTTR provides an R-value based on a fifteen-year weighted average thermal resistance, in order to take into account the observation that for some foam insulating materials the R-value diminishes over time, or by some calculations, an eight-year average R-value.
Other versions of nail base include panels with plywood or OSB on both sides, nail base panels incorporating a reflecting surface, and vented insulation panels. Patent examples:
Insulation Values: Icynene Foam |
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Insulation or other Building Material 9 |
R-Value1 | RSI | Density2 | Perm3 | Absorption4 | Flame Spread 5 |
Smoke6 | Toxicity7 | Aging Effects & Comments |
Icynene® FOAM-POUREDinsulation or pour fill insulation |
423 | 0.72 | .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 | 0.648 - 0.666 | .5-2 10 | low | low | low | Fire safety: may not be left exposed in living area; very good air bypass leak sealing properties |
Insulation Values: Masonry R-Values |
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Insulation or other Building Material 9 |
R-Value1 | RSI | Density2 | Perm3 | Absorption4 | Flame Spread 5 |
Smoke6 | Toxicity7 | Aging Effects & Comments |
Brick, common | 0.20 30 0.80 40 |
0.036 - 0.144 | [30] | ||||||
Brick, 4" face | 0.44 40 |
0.079 | Nil. This is for clay brick. | ||||||
Brick, 4" + 1" reflective air space | |||||||||
Brick, facing or veneer | 0.11 30 | 0.0198 | |||||||
Concrete Block, two rectangular core, 8" | 1.04 | 0.187 | Filled with sand and gravel aggregate [30] We consider this questionable and note that moisture content is omitted. | ||||||
Concrete Block, two rectangular core, 8" | 0.44 + 2.89 = 3.33 |
0.079 + 0.52 = 0.599 | Filled with lightweight aggregate [30], same warning as above. | ||||||
Concrete Block, 4" 72% solid (115#/ft3) |
1.19
|
0.213 | Nil 0.8040 per full thickness |
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Concrete Block, 6" 59% solid |
1.25 | 0.225 | Nil | ||||||
Concrete |
3.95 | 0.711 | |||||||
Concrete Block, 8" 54% solid |
1.45 | 0.261 | 1.1140 per full thickness | ||||||
Concrete |
4.65 | 0.837 | |||||||
Concrete Block 10" 52% solid |
1.55 | 0.279 | Nil | ||||||
Concrete Block, 10" 52% solid perlite filled |
5.65 | 1.017 | |||||||
Concrete Block 12" 48% solid |
1.65 | 0.297 | 1.2840 per full thickness | ||||||
Concrete Block, 12" 48% solid perlite-filled |
7.05 | 1.269 | |||||||
Concrete, poured | 0.08 40 | 0.0144 | |||||||
Hempcrete | ~2 - 3.5 / inch 0.67/cm (1.7/in) - 1.2/cm (3.0/in) |
0.36 - 0.648 / inch 0.67 / cm |
Reader Eric 2022/03/12 Wikipedia same date |
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Lime/Expanded glass | ~1.5 - 2 / inch | 0.27 - 0.36 / inch | Reader Eric 2022/03/12 - sub-slab insulation |
Masonry R-values Source: adapted from "Sample R-Value Calculations" found at www.maconline.org
Notes:
1. Effects of water intrusion on insulating value and R-values are not included in the above nor was there discussion of variation in thermal conductivity at block segments that are solid rather than perlite filled.
2. Additional R-value for a masonry wall constructed using these materials needs to add the insulating value of additional wall components typically included, such as 1" solid foam (polyisocyanurate R 8, extruded polystyrene R 5, expanded polystyrene R 4, or 1" of perlite R 2.7) and
for an exterior air film (winter, no wind, R 0.17), an interior air film (again no air movement, R 0.68), 3/4" of reflective air space (no convective air movement, R 2.89), 1/2" drywall (R 0.45), interior wall cavity insulation (see various fiberglass or other insulating values in this table), to achieve a greater overall R-value than that afforded by the masonry block or brick wall alone.
3. Presumably the R-values given are then calcuated for the overall wall structure, averaging the effects of thermal breaks etc. - Ed.
4. Hempcrete R-Values: NADC, Dion, HEMPCRETE A Simple Solution to Housing Problems [PDF] Northern Alberta Development Council Bag 900-14 2nd fl Provincial Building 9621 - 96 Avenue Peace River, AB T8S 1T4 Main: 780.624.6274 Council Email: nadc.council@gov.ab.ca Dion Tel: 780 283 2837 dion@8thfireinnovations.com - retrieved 2022/03/12 original source: https://nadc.ca/media/1343/hempcrete-dion-lefebvre.pdf
More -M- Materials Insulating Properties |
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Insulation or other Building Material 9 |
R-Value1 | RSI | Density2 | Perm3 | Absorption4 | Flame Spread 5 |
Smoke6 | Toxicity7 | Aging Effects & Comments |
Magnesium Oxide Cement Board MgO | 1.2 | 0.216 | permeable | 0 | see JetBoard Jet-Board.com; 2.1 lbs/sq.ft. for 1/2" thickness | ||||
Mineral Wool Rock Wool Batt | 3.1440 | 0.565 | |||||||
Mineral Wool Rock Wool Blown (Attic) | 3.1040 | 0.558 | |||||||
Mineral Wool Rock Wool Blown (wall) | 3.0340 | 0.545 | |||||||
MINERAL WOOL insulation (Rock Wool) |
3.2 - 3.720
|
0.576 - 0.666 | 1.5-2.5 | 100 | 2% | 0 | 0 | 0 | May collect debris/allergens/mold, also referred-to as rock wool, slag wool, glass wool (but not fiberglass) 3 3/4" - 5" Mineral Wool = R 11 |
Insulation Values: Particleboard to Plaster |
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Insulation or other Building Material 9 |
R-Value1 | RSI | Density2 | Perm3 | Absorption4 | Flame Spread 5 |
Smoke6 | Toxicity7 | Aging Effects & Comments |
Particleboard 5/8" underlayment, per inch | 1.31 | 0.236 | 5/8" particleboard underlayment has an R-value of 0.82 [30] | ||||||
Perlite insulation | 2.5 - 3.720, 30 | 0.45 - 0.666 | 2-11 | High | 0 | 0 | 0 | 0 | See details at PERLITE INSULATION |
Plywood, A/C | 1.4 | 0.252 | Questionable, [need citation] | ||||||
Plywood, 1/4" | 0.31 full thickness |
0.056 | R 0.31 30,40 full thickness | ||||||
Plywood 3/8" | 0.47 full thickness |
0.085 | R 0.47 30,40 full thickness | ||||||
Plywood 1/2" | 0.62 - 0.63 full thickness |
0.112 - 0.113 | R 0.62 - 0.63 30,40 full thickness | ||||||
Plywood 5/8" & Plywood siding 5/8" |
0.77 full thickness |
0.139 | R 0.77 30,40 full thickness | ||||||
Plywood 3/4" Pywood siding 3/4" |
0.93 - 0.94 full thickness |
0.167 - 0.169 | R 0.94 40 full thickness R 0.93 40 |
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Phenolic Foam Insulation R-Values |
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Phenolic foam spray insulation | 4.8 - 721 | 0.864 - 1.26 | |||||||
Phenolic foam insulation Phenolic rigid panel |
8.3 4 - 521
|
1.494 0.72 - 0.90 |
Corrosion problems when in contact with steel roofing & moisture; very good air bypass leak sealing properties |
||||||
Plaster, 1/2" lightweight | 0.32 30 | 0.058 |
Insulation Values: Plastic to Polyurethane |
|||||||||
Insulation or other Building Material 9 |
R-Value1 | RSI | Density2 | Perm3 | Absorption4 | Flame Spread 5 |
Smoke6 | Toxicity7 | Aging Effects & Comments |
Plastic, foamed: Home Foam25 low-density | 3.921 | 0.702 | 0.51 lbs/ft3 | Water-blown Unidentified ingredients 25 Spray or pour application see HomeFoam® above. |
|||||
Polycarbonate sheeting, 10mm Twin-Wall | 4.7 / in ? 1.89 for 10mm |
0.846 / in 0.230 for 10mm |
U-Value 0.53 | ||||||
Polycarbonate film, 6mm "Greenhouse Plastic" |
3. / in ? 0.83 - 0.85 for 6mm |
0.54 0.149 - 0.153 |
Double layer of 6mm R = 1.25 to 1.54 (sources vary) | ||||||
Polycarbonate 16mm Sheet, 5-layer | 2.78 33 (not per in) | 0.500 | |||||||
Polycarbonate sheet, 10-wall, 16mm | 3.34 34 (not per in) | 0.601 | |||||||
Polycarbonate sheet, 10-wall, 40mm | 5.15 34 (not per in) | 0.927 | |||||||
Polyethylene film (greenhoue glazing) |
0.87 32 (not per in) | 0.157 | |||||||
Polyethylene film, 5mm double layer | 1.5 32 (not per in) | 0.27 | |||||||
Polyethylene film, 6mm double layer |
1.7 32 (not per in) | 0.306 | |||||||
Polyethylene foam sheets | 4.12 / 0.4" sheet up to 10.3 / inch |
0.74 / 0.4" sheet up to 1.854 / inch | BUBBLE / CLOSED-CELL FOAM SHEETS | ||||||
Polyethylene foam | 321 | 0.54 | POLYURETHANE FOAM Spray Building Insulation |
...
Polyisocyanurate Foam Insulation R-ValuesPIR Insulation |
|||||||||
Insulation or other Building Material 9 |
R-Value1 | RSI | Density2 | Perm3 | Absorption4 | Flame Spread 5 |
Smoke6 | Toxicity7 | Aging Effects & Comments |
Polyisocyanurate / Polyurethane panel PIR panels |
5.6 - 7.020 | 1.008 - 1.260 | POLYISOCYANURATE FOAM BOARD | ||||||
Polyisocyanurate foam panel or board, foil faced | 6.821 - initial, pentane |
1.224 1.296 0.99 |
Rigid panel insulation board with foil facing both sides, edges exposed Aged R-values for foam panels assume aging in-situ for 5-10 years. |
||||||
Polyisocyanurate foam panel Dow TUFF-R | 6.5 32 | 1.17 | 2 ASTM D1622, pcf |
<0.03 32 | |||||
Polyisocyanurate spray, poured, or board insulation | 4.3 - 8.321 5.5 - 6.2 to 7.04 - 8.0 |
0.774 - 1.494 0.99 - 1.116 |
2 | 2-3 | 0 | 25 | 55-200 | CO | Closed cell, HCFC or CFC gases; Also see INSULATION CHOICES |
Polyisocyanurate composite insulation | 2.8 (5.8-6.2) |
0.504 (1.044 - 1.116) |
2.0 | 2-3 | Closed cell Foil faced21 |
...
Polystyrene Foam Insulation R-ValuesEPS Expanded Polystyrene Insulation (beadboard)
|
|||||||||
Insulation or other Building Material 9 |
R-Value1 | RSI | Density2 | Perm3 | Absorption4 | Flame Spread 5 |
Smoke6 | Toxicity7 | Aging Effects & Comments |
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 | 0.414 | 5-25+ | 10-400 | Static charge makes particles hard to control | ||||
Polystyrene board or beadboard 8 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 (XPS) insulation low-density |
3.85 3.6 - 4.721 |
0.648 0.648 - 0.846 |
See POLYSTYRENE FOAM INSULATION Also see INSULATION CHOICES |
||||||
Polystyrene Expanded beadboard | 4.040 | 0.72 | |||||||
Polystyrene board, extruded expanded high-density (EPS) Molded |
5 - 5.421 4.221 |
0.90 - 0.972 0.756 |
|||||||
EPS Expanded polystyrene | see POLYSTYRENE foam | ||||||||
XPS Extruded polystyrene | 4 | also see Owens Corning FORMULAR FANFOLD XPS Re-Siding BOARD [PDF] - 1/4" = R-1. | |||||||
Polystyrene board, Extruded XPS | 3.6 - 4.042 | 0.648 - 0.72 | See Owens Corning FORMULAR FANFOLD XPS Re-Siding BOARD [PDF] - 1/4" = R-1. |
||||||
Polystyrene board, Expanded EPS | 4.5 - 5.040, 42 | 0.81 - 0.90 | 1.5 | 1.2-3.0 | Closed cell |
... TEST ...
Polyisocyanurate / Polyurethane Foam Insulation R-Values |
|||||||||
Insulation or other Building Material 9 |
R-Value1 | RSI | Density2 | Perm3 | Absorption4 | Flame Spread 5 |
Smoke6 | Toxicity7 | Aging Effects & Comments |
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 |
0.90 - 1.224 0.99 - 1.17 Initial |
2.0 | 2-3 | 0 | 30-50 | 155-200 | CO | Closed cell foam spray insulation; 0-12% shrinkage, Fire safety: |
Polyurethane foam insulation rigid panels | 7-821 - Initial 6.25 - aged 5 to 10 years |
1.28 -1.44 1.125 Aged 5-10 Yrs |
CHC/HCFC expanded foam | ||||||
Polyurethane foam insulation rigid panels | 6.821 - Initial 5.5 - aged 5 to 10 years |
1.224 0.99 |
Pentane expanded foam | ||||||
Polyurethane spray foam insulation rigid panels, foil-faced | 7.9 - 8.4 | 1.422 - 1.512 | Pentane expanded foam, presence of an air-gap may increase panel performance. RSI = 45-48 |
||||||
Polyurethane foamed in place | 6.2540 | 1.125 | |||||||
Polyurethane spray foam insulation - open cell insulation | 3.621 - 7 (est) | 0.648 | Expands & seals more than closed-cell; lower cost; pourable-version available for building retrofit; |
Insulation Values: Reflective to Rockwool |
|||||||||
Insulation or other Building Material 9 |
R-Value1 | RSI | Density2 | Perm3 | Absorption4 | Flame Spread 5 |
Smoke6 | Toxicity7 | Aging Effects & Comments |
Radiant barriers | 0 (none) | 0 | Blocks radiant heat gain/loss See RADIANT BARRIERS |
||||||
Reflective barrier insulation | 0 - 1720 | 0 - 3.06 | Varies by product. Example: |
||||||
Rock Wool Batts Slag wool Batts |
3 - 3.8520 | 0.54 - 0.693 | See more details at MINERAL WOOL | ||||||
Rock Wool, Slag wool Loose Fill insulation R-value |
2.5 - 3.720 | 0.45 - 0.666 |
Roofing Material R-Values |
|||||||||
Insulation or other Building Material 9 |
R-Value1 | RSI | Density2 | Perm3 | Absorption4 | Flame Spread 5 |
Smoke6 | Toxicity7 | Aging Effects & Comments |
Roofing: Asphalt shingles | 0.4430,40 | 0.0792 | |||||||
Roofing: built-up 3/8" thick plies | 0.3330 | 0.0594 | |||||||
Roofing: wood shingles | 0.9430 0.9740 |
0.1692 0.1746 |
Also see below at "wood". The use of this R-valuye is highly questionable since wood shingle roofs do not block air flow whatsoever. |
...
Other "S" Materials |
|||||||||
Insulation or other Building Material 9 |
R-Value1 | RSI | Density2 | Perm3 | Absorption4 | Flame Spread 5 |
Smoke6 | Toxicity7 | Aging Effects & Comments |
Sheeps Wool Insulation | 3.6 blown-in 4.3 batts |
0.648 0.774 |
Wool or recycled fabric insulation is also used as pipe lagging. |
||||||
Silica Aerogel | 10 | 1.8 | |||||||
Steel siding | 0.6140 full thickness, hollow-backed | ||||||||
Snow | 1 | 0.18 | |||||||
Soil or "dirt" | 0.25 - 1 0.80 typical at 20% moisture |
0.045 - 0.18 | Depends on soil properties: density, moisture content, moisture movement See SOIL R-VALUES |
||||||
Straw Bale | 1.45 | 0.261 |
(Commins 1998) [36] |
||||||
Stucco, conventional plaster/cement | 0.20 | 0.036 | [30] |
...
Building Siding R-Values |
|||||||||
Insulation or other Building Material 9 |
R-Value1 | RSI | Density2 | Perm3 | Absorption4 | Flame Spread 5 |
Smoke6 | Toxicity7 | Aging Effects & Comments |
Aluminum siding | 0.61 | 0.11 | R 0.6140 full thickness, hollow-backed | ||||||
Aluminum siding w/ 1/2" insulating board backer | 1.80 | 0.324 | R 1.8040 full thickness, | ||||||
Brick veneer 4" | 0.44 | 0.0792 | R 0.4440 full thickness | ||||||
Hardboard siding 1/2" | 0.34 | 0.0612 | R 0.3440 full thickness | ||||||
Logs (solid wood) | 1.2540 | 0.225 | |||||||
Logs (solid Cedar) | 1.3340 | 0.2394 | Log wall R-Values vary16 | ||||||
Log slab/board siding | see Wood siding / clapboards | ||||||||
Plywood siding 5/8" | 0.77 full thickness |
0.1386 | R 0.7740 full thickness | ||||||
Plywood siding 3/4" | 0.93 full thickness |
0.1674 | R 0.9340 full thickness | ||||||
Vinyl Siding | 0.61 see notes |
0.1098 | Low | 0 | 1/16" (0.175") to 3/32" (0.093") thick vinyl siding, hollow-backed | ||||
Vinyl siding | 0.61 | 0.1098 | 0.6140 full thickness, hollow-backed | ||||||
VInul siding w/ 1/2" insulating board backer | 1.80 | 0.324 | 1.8040 full thickness | ||||||
Wood shingle siding, single course | 0.8730 |
0.1566 | |||||||
Wood clapboard siding, 1/2-inch clapboard or shiplap | 0.8040 0.8130 |
0.1440 0.1458 |
...
Insulation or other Building Material 9 |
R-Value1 | RSI | Density2 | Perm3 | Absorption4 | Flame Spread 5 |
Smoke6 | Toxicity7 | Aging Effects & Comments |
Tectum™ insulated roof panels | 2.0 | 0.36 | Tectum: a patented cementitious wood fiber EPS-core insulating roof deck tile, plank, or panel of several thicknesses. | ||||||
Thinsulate | 5.75 | 1.035 | Clothing insulation, not used in buildings |
Insulation Values: Urea Formaldehude UFFI to Vinyl |
|||||||||
Insulation or other Building Material 9 |
R-Value1 | RSI | Density2 | Perm3 | Absorption4 | Flame Spread 5 |
Smoke6 | Toxicity7 | Aging Effects & Comments |
Urea terapolymer foan | 4.4840 | 0.8064 | |||||||
Urea Formaldehyde Foam Panels or in-wall spray | 4 - 4.621 | 0.72 - 0.828 | Formaldehyde outgassing concerns, especially new, possibly | ||||||
UFFI insulation (Urea Formaldehyde Foam) |
4.2 5.2521 |
0.756 0.945 |
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 |
...
Insulation or other Building Material 9 |
R-Value1 | RSI | Density2 | Perm3 | Absorption4 | Flame Spread 5 |
Smoke6 | Toxicity7 | Aging Effects & Comments |
VERMICULITE insulation | 2.1319, 40 - 3.0 2.10 - 3.720 |
0.3834 |
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 |
Vinyl Siding | 0.61 full thickness |
0.1098 | Low | 0 | 1/16" (0.175")to 3/32" (0.093") thick vinyl siding, hollow-backed | ||||
Vinyl siding | 0.61 | 0.1098 | 0.6140 full thickness, hollow-backed | ||||||
Vinyl Siding, Insulated | 2.0 | 0.36 | Manufactured with rigid foam plastic insulation laminated to thje siding ASTM D7793 requires insulated siding to demonstrate a INSULATED VINYL SIDING as HOME INSULATION [PDF] Vinyl Siding Institute |
||||||
Vinyl Thin Film Window Covering | 0.07 - 0.81 see notes |
0.0126 - 0.1458 | Low | 0 | U-value and emissivity values vary depending on the type of film, with emissivity values from 0.07 to 0.81 - DeBusk [29] |
Insulating value & other properties of water |
|||||||||
Insulation or other Building Material 9 |
R-Value1 | RSI | Density2 | Perm3 | Absorption4 | Flame Spread 5 |
Smoke6 | Toxicity7 | Aging Effects & Comments |
Water | 0.004 | 0.0007 | Roughly 1 g/ml or more-accurately, the density of water is 0.9998395 g/ml at 4.0° Celsius (39.2° Fahrenheit). |
The R-value of water has little practical application but in various discussions is placed around R 0.004 - effectively almost zero. |
...
Insulating R-Values of Windows |
|||||||||
Insulation or other Building Material 9 |
R-Value1 | RSI | Density2 | Perm3 | Absorption4 | Flame Spread 5 |
Smoke6 | Toxicity7 | Aging Effects & Comments |
Windows, single glazed | 0.9740 full thickness |
0.1746 | |||||||
Single glazed window w/ storm | 2.0040 full |
0.36 | thickness May vary widely depending on air leaks |
||||||
Double insulated glass window 3/16" air space | 1.6140 full thickness |
0.2898 | |||||||
Double insulated glass window 1/4" air space | 1.6940 full thickness |
0.3042 | |||||||
Double insulated glass window 1/2" air space | 2.0440 full thickness |
0.3672 | |||||||
Double insulated glass 3/4" air space | 2.3840
|
0.4284 | Caution: larger air gaps can cause heat loss due to internal convection currents! |
||||||
Double insulated glass 1/2" w low-E 0.20 | 3.1340 full thickness |
0.5634 | |||||||
Glass w/suspended film | 2.7740 full thickness |
0.4986 | |||||||
Glass w/ 2 suspended films | 3.8540 full thickness |
0.693 | |||||||
Glass w/ 2 suspended films, Low-E | 4.0540 full thickness |
0.729 | |||||||
Triple insulated glass 1/4" air spaces | 2.5640 full thickness |
0.4608 | |||||||
Triple insulated glass 1/2" air spaces | 3.2340 full thickness |
0.5814 | |||||||
Added insulation at windows from tight-fitted drapes, shades, closed-blinds | +0.2940 | 0.0522 | |||||||
Double celled blinds with side rails a | 1.6 - 4.7 | ||||||||
Also see insulating properties of glass at - G - |
a. R- Value of Double Celled Window Blinds with Side Rails:
Thanks to Ted Chaban for this note, 2024/04/04, possible references include:
Cellular Window Shades (a vendor of this product) gives R-values for cellular type window blinds ranging from R 1.6 for single-celled light filtering, up to R 4.7 for double celled black-out type window shades with side tracks. - 2024/04/04 original source: https://cellularwindowshades.com/content/33-rvalue-and-insulating-cellular-window-treatments
The actual R-value provided by single or double-celled window blinds will vary by product and product features and also on the percentage of time and time of day during which such shades or blinds are left partly open.
Cameron Bonnell, Louisa Bachman, Caitlin Bugash, Josiane Rosario, Lucas Ghilardi, "A Plan of Action to Green Buildings on Campus Recommendation to the University of Massachusetts Amherst" [PDF] - retrieved 2024/04/04 original source: https://icons.cns.umass.edu/sites/default/files/student-work/2020-06/greenbuildingsustainablebuildingsrecommendationfinaldraft.pdf
Coffin, Donna. (2012). Bulletin #7214, Maine Home Energy: Insulated Interior Window Treatments and Coverings - Cooperative Extension Publications - University of Maine Cooperative Extension. Retrieved May 3, 2020, from https://extension.umaine.edu/publications/7214e/
Kirimtat, Ayca, Basak Kundakci Koyunbaba, Ioannis Chatzikonstantinou, and Sevil Sariyildiz. "Review of simulation modeling for shading devices in buildings." Renewable and Sustainable Energy Reviews 53 (2016): 23-49.
...
Insulation Values: Wood |
|||||||||
Insulation or other Building Material 9 |
R-Value1 | Density2 | Perm3 | Absorption4 | Flame Spread 5 |
Smoke6 | Toxicity7 | Aging Effects & Comments |
|
Wood R-Values |
1.01 - 1.41 (softwoods) 0.71 (hardwoods) 1.2540 |
0.1818 - 0.2538 0.1278 0.225 |
The R-value of wood R-value of typical 3/4" Wood: 2" nominal Wood 2x4 Wood 2x6 |
||||||
Wood Logs & Lumber (Cedar) | 1.3340 | 0.2394 | Log wall R-Values vary16 | ||||||
Wood door, solid, per inch | 1.56 | 0.2808 | Varies by species, no authoritative source. |
||||||
Wood Fiber Insulation Batts | 1 - 3.4 | 0.18 - 0.612 | BALSAM WOOL BATT INSULATION |
||||||
Wood Fiber Insulation Panels | 3.3 | 0.594 |
and SHEATHING, FIBERBOARD - home |
||||||
Wood, soft | 1.25 | 0.225 | Questionable, [need citation] | ||||||
Wood Flooring, assume 3/4" hardwood | 0.68 | 0.1224 | [need citation] | ||||||
Wood sheathing panels (Plywood,OSB) | 2.521 | 0.45 | [need citation] | ||||||
Wood shingle siding, single course | 0.8730 |
0.1566 | |||||||
Wood siding, 1/2-inch clapboard or shiplap | 0.8040 0.8130 |
0.144 0.1458 |
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.
XPS polystyrene | see POLYSTYRENE foam |
...
Below you will find questions and answers previously posted on this page at its page bottom reader comment box.
It is quite common to skim a wall with a cement coat (say approx 10mm thick) as a base on which to then apply a finish coat of lightweight plaster.
I can find the R-value for lightweight plaster, but nothing for cement skims applied to vertical walls - everything relates to concrete only (and usually horizontal concrete slabs).
I strikes me that the cement skim layer underlying the plaster must also have an insulating property........ but I cannot find any R-values for thin cement skims applied to vertical walls. Can you help please.....any ideas would be most welcoe.
- Anonymous by private email 2022/05/10
Moderator reply: 10mm concrete has an R-value of about R 0.1
Right on this page at CONCRETE R-Values we give the insulating values of various types and thickensses of concrete.
You'll see our statement that a ypical residential weight concrete 8" wall has an R-value of about R 2.5.
That is, ordinary concrete has an R-value of 0.08 - 0.3125 per inch, depending on various sources and variations in concrete mix.
Using the first data point of R 2.5 for an 8-inch thick wall, that's the high end of the R-value range (and in my opinion optimistic) and would be
R 0.35 per inch.
Since 10mm = 0.3937 inches or about 0.4 inches
The highest-estimate R-value of a concrete skim coat would be R0.35 x 0.4in = R 0.14 - maximum,
and a minimum of
R-0.032 at the lower end of the concrete R-values range.
A plausible guess therefore, at mid-range would put the concrete skim coat R-value at 0.1
...
Help me out by a little education: what use is made of the data when the R- is so low?
I guessed that even a very-low R-value, if over a sufficiently-large area, and with enough indoor-vs-outdoor temperature difference, might be of interest.
Reader follow-up:
Thank you very much for your helpful reply. I always thought the R-value would be quite small, akin to or less than lightweight plaster, but nevertheless I was interested as to what it might be.
I am very happy for this question to be made public, provided that my name, email and any other personal data are kept private. Also, if possible I do not want to be identified as a contributor. But please feel free to publish the question, and the answer.
Your website is incredibly comprehensive and a real find - well done.
...
Although the R-value for a cement skim coat might be small, it is still there.
Everyone would usually factor in a 13mm coat of lightweight plaster if it was present, and use an R-value of about 0.081, and this is in the ball-park of 0.10 which is a plausible average R-value for a 10mm cement skim coat. So I reckoned that if I was taking the plaster coat into account, I may as well account for the cement skim coat too.
The question might well be put, "why bother?" And I think your answer hit the nail on the head. It's because of the large areas of wall that are being dealt with.
In the UK, when domestic houses are bought and sold, a formal Energy Performance Certificate (EPC) has to be produced for the house in question so that the buyer can see what they are letting themselves in for in terms of future energy costs (a hot topic at the moment!).
A larger house might have 400m2 of wall-area and so these smaller R-values add up, even though they might be overshadowed by the insulation in the cavity of the wall which is providing most of the wall's overall R-value. Every little helps, as they say.
How to calculate the U-Value and R-Value of 7 cms thick and 4,4 cms thick plastic bricks
Hello. I'm looking for some advice. I want to know how to calculate the U-Value and R-Value of 7 cms thick and 4,4 cms thick plastic bricks (100% plastic mixing recycled bricks). Heat dissipation of both of them is 62.59% (7 cms) and 33,52% (4,4 cms). Any idea? - On 2022-03-11 by Samuel -
Reply by Inspectapedia Com Moderator (mod) - how to calculate the U-Value and R-Value
@Samuel,
Sure,
Look at the Recommended Articles on this page and you'll see links to HEAT LOSS RATE CALCULATIONS - R, U, & K VALUES R-Value and U-value calculation procedures.
...
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