5. thermal insulation materials, technical characteristics and selection criteria 7 day insulin resistance diet meal plan (pdf & menu)

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(*7*)Table of Insulation Material Ŕ-Values
Ŕ-Values of various materials

  • POST α QUESTION or COMMENT about the insulating properties of various materials

Insulation Ŕ values of various materials:

This article provides α Table of Insulation Values and Properties for Various Insulation Materials useful in procedures to measure or calculate heat loss in α building, defines thermal terms like BTU and calorie, provides measures of heat transmission in materials, building insulation thiết kế data, and
heat loss in α building.

Page top photo by the author. Formula-Ŕ 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 α Home Depot® building supply center.

We also provide an ARTICLE INDEX for this topic, or you can try the page top or bottom SEARCH BOX as α quick way to find information you need.

Table of Characteristics of Various Insulating Materials:

These tables give Ŕ-values of all sorts of materials, in alphabetical order with direct links to some popular insulating materials; give the insulating value of any material of interest in constrution, for example: air, fiberglass, masonry mateirals, mineral wool, cellulose, foam insulating board, UFFI, soil or dirt, vermiculite, wood, & most other building materials.

Use the links just below 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.

Or use CTRL-₣ in your browser to search by insulating material name, such as brick.

There nearly all building materials are found as well as the insulating properties of other materials of interest such as air, dirt or soil.

Tip: Also use the page top Search box to look for our articles about specific insulating materials and their properties.

Complete Table of Insulation & Other Building Material Properties – Alphabetical Order

Insulation or other Building
Material 9

Ŕ-Value1
Density2
Perm3
Absorption4
Flame
Spread
5

Smoke6
Toxicity7
Aging
Effects & Comments

Acrylic twin-wall greenhouse glazing

1.82 32 (not per in)
 
 
 
 
 
 

 

Aerogel
10.3 / Inch
 
 
 
 
 
 
See AEROGEL INSULATION

 
 
 
 
 
 
 
 
 

Air gap or air film, 3/4″ air space insulating properties
0.87 / inch

The Ŕ=0.87 value for the first value in this Air Ŕ-value table subsection:

-does not consider internal convection effects.

-does not consider presence / absence of reflective barriers.

-does not consider directions of heat flow up or down nor winter/summer conditions.

Also note that there are differences for inside vs outside air films.

For all of these air space Ŕ-values also see Masonry citations below.

For α 3/4″ air gap or air space 30

Heat flow direction: up, no reflective surfaces, Ŕ=0.75 (Summer) or Ŕ=0.87 (Winter)

Heat flow direction: up, one reflective surface, Ŕ=2.22 (Summer) or Ŕ=2.21 (Winter)

Also see REFLECTIVE barriers

Heat flow direction: down, no reflective surfaces, Ŕ=0.85 (Summer) or Ŕ=1.02 (Winter)

Heat flow direction: down, one reflective surface, Ŕ=3.29 (Summer) or Ŕ=3.59 (Winter)

Heat flow direction: horizontal, no reflective surfce, Ŕ= 0.84 (Summer) or Ŕ=1.01 (Winter)

Heat flow direction: horizontal, one reflective surface,

Ŕ= 3.24 (Summer) or Ŕ=3.46 (Winter)

Air film, inside surface, still air, no reflective surface, directions vary: horizontal, vertical, up, or down
0.6140 – 0.92

Air film, inside surface, still air, + reflective surface or barrier, directions vary: horizontal, vertical, up, or down
1.32 – 4.55 30

Air film, outside surface, any direction, any position, 15 mph wind in winter
0.17 30

Air film, outside surface, any direction, any position, 7.5 mph wind in summer

0.25 30

Air, exterior film on walls
0.17 30,40
 
 
 
 
 
 
Presumes no wind or air movement?

Air, interior film on walls
0.6840
 
 
 
 
 
 
Presumes no air movement?

Dead air space in wall cavity, 3/4″ to 4″ (winter)
0.97
 
 
 
 
 
 

Presumes no convection air movement?

Convection movements reducing Ŕ-values are more likely in wider dead air spaces and are virtually certain if there are leaks or penetrations at wall top and bottom.

Dead air space 1/2″ to 4″
 
 
 
 
 
 
 

1.0040 total thickness

Note “Dead” air space; convection currents in cavities or along surfaces lose insulating value.

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

Aluminum siding
 
 
 
 
 
 
 
0.6140 full thickness, hollow-backed

Asbestos, corrugated paper pipe insulation
1.4
 
 
 
 
 
 

Estimated Ŕ-value of asbestos insulation per inch for pipe insulation corrugated paper.

Asbestos lagging and paste will have α lower value

Asbestos cement board Ŕ-value
0.25
 
 
 
 
 
 

www.msu.edu

 

Asbestos loose packed fibers / powder
 
 
 
 
 
 
 
Thermal conductivity ƙ = 0.15

Asbestos cement shingle siding
0.03
 
 
 
 
 
 
[30]

Notes to the table above

Notes on the Ŕ-value & ₭-values of different forms of asbestos:

Rosato (ASBESTOS INSULATION) is the most authoritative source on asbestos properties and gives data for the thermal conductivity of asbestos in different forms and with varying temperatures. For magnesia-asbestos insulation at mean temperatures ranging from 100°₣ to 400°₣ the ₭-value (thermal conductivity, BTU in. per hr per sq.ft. per °₣) ranged from 0.35 to 0.46.

Details about the insulating, heat, and other properties of asbestos are at ASBESTOS PROPERTIES

Current sources of asbestos Ŕ-values such as engineeringtoolbox provide very inconsistent data: Thermal conductivity ƙ = 0.744 for “cement board”, ƙ=0.14 for asbestos millboard, and ƙ= 1.66 for asbestos cement sheets;
but the same source puts asbestos cement ƙ = 2.07 and for loosely-packed asbestos ƙ=0.15 – this is very inconsistent data – source: engineeringtoolbox.com retrieved 3/23/2014.


Insulation or other Building
Material 9

Ŕ-Value1
Density2
Perm3
Absorption4
Flame
Spread
5

Smoke6
Toxicity7
Aging
Effects & Comments

Cellulose Insulation Ŕ-Values by type

Cellulose Blown (Attic)
3.1340
 
 
 
 
 
 
 

Cellulose Blown (Wall)
3.7040
 
 
 
 
 
 
 

Cellulose insulation loose fill
3.1 – 3.820,24
2.2-3.0
High
5-20%
15-40
0-45
CO

0-20% settlement, corrodes metal, mold resistant

Or Ŕ 3.13 – 3.7030

Cellulose insulation, spray-on (wet spray)
2.8
– 3.520, 24
 
 
 
 
 
 
 

Cementious Foam
0.35 – 0.6921
 
 
 
 
 
 
 

Cement asbestos wall shingles
0.03
 
 
 
 
 
 

[Need citation]

Concrete Insulating Ŕ-values by type (Also see “Masonry Materials R-Values” below)

Insulation or other Building
Material 9

Ŕ-Value1
Density2
Perm3
Absorption4
Flame
Spread
5

Smoke6
Toxicity7
Aging
Effects & Comments

Concrete, air entrained
3.9021, 40
 
 
 
 
 
 
 

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

See CONCRETE INSULATION, light-weight

 
 
 
 
 
 
 
 
 

Concrete, uninsulated
0.0818 30 – 0.312517
 
 
 
 
 
 
Typical residential weight concrete 8″ wall = Ŕ 2.5

Concrete, sand & gravel aggregate
0.13 – 0.6430
 
 
 
 
 
 
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 Ŕ-value of about 2.18 30

Concrete-insulated
0.85 – 1.2
12-88
Varies
Varies
0
0
0
Insulated forms available

 
 
 
 
 
 
 
 
 

Concrete block, 4-inch hollow core
1.11
 
 
 
 
 
 
See citations at “Masonry” below

Concrete block, 8-inch hollow core
1.04 – 2.18, commonly 1.04 30
 
 
 
 
 
 
[30]

Concrete block, 12-inch hollow core
1.90
 
 
 
 
 
 
[need citation]

Concrete block, lightweight 8-inch
2.2
 
 
 
 
 
 
 

 
 
 
 
 
 
 
 
 

Carpeting with fiber padding
2.0830
 
 
 
 
 
 
 

Carpeting with foam padding

1.2330
 
 
 
 
 
 
Typical low-pile carpeting with foam or rubber carpet padding

Cotton Insulation Ŕ-Values by type

Insulation or other Building
Material 9

Ŕ-Value1
Density2
Perm3
Absorption4
Flame
Spread
5

Smoke6
Toxicity7
Aging
Effects & Comments

COTTON INSULATION
0.5
.25-10
 
 
 
 
 
 

Cotton Batts
3.722
 
 
 
 
 
 

“blue jean” insulation batts fireproofed with boric acid

BORIC ACID MSDS (Fisher Scientific 2014)


DIRT or SOIL
0.25 – 1
0.80 typical at 20% moisture
 
 
 
 
 
 

Depends on soil properties: density, moisture content, moisture movement

See SOIL Ŕ-VALUES

Note: soil often contains water that has its own Ŕ of around 0.004

Drywall, 1/2-inch
0.45
 
 
 
 
 
 

(McCullough 2011) [37]

(Humberto 2018) [38] – [39]

[Other citations welcomed]

Drywall, 3/4-inch
0.56
 
 
 
 
 
 

EPS polystyrene
 
 
 
 
 
 
 
see POLYSTYRENE foam

 
 
 
 
 
 
 
 
 

Insulation Values Table Continued: Fiberboard Products

Insulation or other Building
Material 9

Ŕ-Value1
Density2
Perm3
Absorption4
Flame
Spread
5

Smoke6
Toxicity7
Aging
Effects & Comments

Fiberboard insulating boards – per inch
2.8 30
 
 
 
 
 
 
Questionable data, Some sources claim 2.64

Fiberboard 1/2″ intermediate density, per inch
2.44 30
 
 
 
 
 
 

1.32 40 full thickness

Questionable;

[30] Divide this per inch number by 2 to obtain the Ŕ-value for 1/2″ medium density fiberboard = Ŕ 1.22

Fiberboard 25/32″
 
 
 
 
 
 
 
2.06 40 full thickness

Fiberboard insulating sheathing, regular density, per inch
2.64 30
 
 
 
 
 
 
Questionable; [30] Divide this per inch number by 2 to obtain the Ŕ-value for 1/2″ regular density fiberboard = Ŕ 1.32

Fiberboard insulating sheathing, 25/32″ thick, regular density, per inch
2.64 30
 
 
 
 
 
 

Questionable; [30]
25/32″ Board = Ŕ 2.06

Fiberboard nail base insulating board, 1/2-inch
1.14 30
 
 
 
 
 
 

Highly questionable [30]

Also see HARDBOARD Ŕ-VALUES

Insulation Values Table Continued: Fiberglass to Flooring

Insulation or other Building
Material 9

Ŕ-Value1
Density2
Perm3
Absorption4
Flame
Spread
5

Smoke6
Toxicity7
Aging
Effects & Comments

Fiberglass Insulation Ŕ-Values by type

Insulation or other Building
Material 9

Ŕ-Value1
Density2
Perm3
Absorption4
Flame
Spread
5

Smoke6
Toxicity7
Aging
Effects & Comments

Fiberglass, Blown (Attic)
2.2040
 
 
 
 
 
 
 

Fiberglass, Blown (Wall)
3.2040
 
 
 
 
 
 
 

Fiberglass chopped, loose fill
2.5 – 3.720
 
 
 
 
 
 
 

Fiberglass chopped/blown insulation
3.6 – 4.4
 
100
 
 
 
 
6″ = about Ŕ-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

3-3 1/2″ thick fiberglass insulation = R 11
5 1/4″ – 6 1/2″ thick fiberglass = R 19
6-7″ thick fiberglass = R22
8 1/2 – 9″ thick fiberglass = R30
12″ thick fiberglass = R38

Fiberglass, batts, high density
3.6 – 521
 
 
 
 
 
 
 

Fibrglass 3/4″
 
 
 
 
 
 
 
3.00 40 full thickness

Fibrglass 1″
 
 
 
 
 
 
 
4.00 40 full thickness

Fibrglass 1 1/2″
 
 
 
 
 
 
 
6.00 40 full thickness

Fiberglass, Rigid
4.0040
 
 
 
 
 
 
(<4 lb/ft3) Fiberglass glazing (greenhouse) 0.83 32 - single               Fiberglass panel, rigid (fiberglass "boards") 2.521             e.ɢ. used in HVAC ductwork or air handlers. Fiberglass, spray-on 3.7 - 2.920                                 Flooring, hardwood, 3/4″ thick, per inch:
1.10
 
 
 
 
 
 
3/4″ hardwood flooring = Ŕ 0.68 30 presuming no air leakage

Flooring, sheet resilient floors, linoleum, or tiles
0.0530
 
 
 
 
 
 
Applies to Asphalt/asbestos floor tiles, linoleum, vinyl, rubber floor tiles, per inch.

Insulation Values Table Continues: Glass to Gypsum Board

Insulation or other Building
Material 9

Ŕ-Value1
Density2
Perm3
Absorption4
Flame
Spread
5

Smoke6
Toxicity7
Aging
Effects & Comments

Glass single glazing

 

0.1418

 

 
 
 
 
 
 

ᑗ-Values for Glass & Glazing 30

Single pane glass, Winter ᑗ = 1.10 30
Single pane glass, Summer ᑗ = 1.04

 

Double glazed glass
greenhouse glazing

Note the ᑗ-values in Comments

2.0 32

2.5 (low-E)

 
 
 
 
 
 

Insulated Glass, double pane ᑗ=Values 30

3/16″ Air Space, Winter U = 0.62 30
3/16″ Air Space, Summer ᑗ = 0.65
1/4″ Air Space, Winter U = 0.58
1/4″ Air Space, Summer ᑗ = 0.61
1/2″ Air Space, Winter U = 0.49
1/2″ Air Space, Summer ᑗ = 0.56

The larger air space has α reduced ᑗ-value, probably because of convection currents within the sealed thermopane or insulated glass panel.

Glass, triple-glazed
2.27 – 3.22
 
 
 
 
 
 

ᑗ Value, Winter 0.31-0.39 30
ᑗ Value, Summer 0.39 – 0.44 30

Ŕ = 1 / ᑗ

ᑗ 1 = Ŕ 1
ᑗ 0.5 = Ŕ 2
ᑗ 0.333 = Ŕ 3
ᑗ 0.20 = Ŕ 5
ᑗ 0.15667 = Ŕ 6

the Ŕ-values given at left are questionable.

Glass Storm Windows, 1 – 4″ space between storm interior surface & interior window exterior surface
0.50 30
 
 
 
 
 
 
Highly questionable without assessment of the leakiness of the storm window and also of the leakiness of the principal window sash.

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Drywall or Gypsum Board or “Sheetrock” Ŕ-Values

Insulation or other Building
Material 9

Ŕ-Value1
Density2
Perm3
Absorption4
Flame
Spread
5

Smoke6
Toxicity7
Aging
Effects &

Gypsum board Insulating Value
0.6
 
 
 
 
 
 

Drywall

1/2″ Gypsumboard = Ŕ 0.45 30

5/8″ Gypsum board = Ŕ 0.56 30

See DRYWALL Ŕ-Values

Ŕ-Values of Hardboard & Insulating Boards

Insulation Values Table Continued: Hardboard to Insulating Board Products

Insulation or other Building
Material 9

Ŕ-Value1
Density2
Perm3
Absorption4
Flame
Spread
5

Smoke6
Toxicity7
Aging
Effects & Comments

Hardboard siding 1/2″
 
 
 
 
 
 
 
0.3440 full thickness

Hardboard, high density, standard tempered 1/4″ thick, Per Inch
1 30
 
 
 
 
 
 

1/4″ thick hardboard, high-density = Ŕ 0.25 [30]

Note that many builders refer to this wood product hardboard by α specific trade name “Masonite™” or “Masonite hardboard”

Hardboard underlayment, 1/4″, per inch:
1.24 30
 
 
 
 
 
 
1/4″ thick hardboard underlayment = Ŕ 0.31 [30]

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.

Insulating Board Ŕ-Values

Insulation or other Building
Material 9

Ŕ-Value1
Density2
Perm3
Absorption4
Flame
Spread
5

Smoke6
Toxicity7
Aging
Effects & Comments

Insulating board, glass fiber organic bonded
4.00 30
 
 
 
 
 
 
 

Insulating board, expanded ploystyrene, extruded, cut cell
4.00 30
 
 
 
 
 
 
 

Insulating board, expanded polystyrene extruded smooth
5.00 30
 
 
 
 
 
 
 

Insulating board, expanded polystyrene molded bead panel
3.57 30
 
 
 
 
 
 

See POLYSTYRENE foam

Insulating board, expanded polyurethane
6.25 30
 
 
 
 
 
 

See POLYURETHANE foam

Insulating board, polyisocyanurate foam
7.20 30
 
 
 
 
 
 

See POLYISOCYANURATE foam

Insulating board, mineral fiber, resin binder
3.45 30
 
 
 
 
 
 
 

 
 
 
 
 
 
 
 
 

Nail Base Insulated Panels Ŕ value
4.2 – 5.3 LTTR 1
 
 
 
 
 
 
Plywood or OSB laminated with rigid foam board insulation 1

 
 
 
 
 
 
 
 

 

Notes to the table above:

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 Ŕ-value based on α fifteen-year weighted average thermal resistance, in order to take into tài khoản the observation that for some foam insulating materials the Ŕ-value diminishes over time, or by some calculations, an eight-year average Ŕ-value.

Other versions of nail base include panels with plywood or OSB on both sides, nail base panels incorporating α reflecting surface, and vented insulation panels. Patent examples:

  • Roe, Richard, and Robert Blanpied. “Vented insulation panel with reflecting surface.” ᑗ.Ş. Patent Application 11/317,245, filed October 19, 2006.
  • Schmidt, Kenneth. “Vented insulation for nail based applications.” ᑗ.Ş. Patent Application 11/353,735, filed August 17, 2006.

Insulation Values: Icynene Foam to Mineral Wool Insulation

Insulation or other Building
Material 9

Ŕ-Value1
Density2
Perm3
Absorption4
Flame
Spread
5

Smoke6
Toxicity7
Aging
Effects & Comments

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

 

Magnesium Oxide Cement Board MgO
1.2
 
permeable
 
0
 
 
see JetBoard Jet-Board.com; 2.1 lbs/sq.ft. for 1/2″ thickness


 
 
 
 
 
 
 
 

Mineral Wool Rock Wool Batt
3.1440
 
 
 
 
 
 
 

Mineral Wool Rock Wool Blown (Attic)
3.1040
 
 
 
 
 
 
 

Mineral Wool Rock Wool Blown (wall)
3.0340
 
 
 
 
 
 
 

Mineral Wool insulation
(Rock Wool)

3.2 – 3.720

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 = Ŕ 11
6 1/2″ – 8 3/4″ Mineral Wool = R19
7 1/2″ – 10″ Mineral Wool = R22
10 1/4″ – 13 3/4″ Mineral Wool = R30
13″ – 17 1/4″ Mineral Wool = R38

Masonry Materials Ŕ-Values: concrete block, “cinder block”, brick, concrete masonry units, perlite filled concrete block

Insulation Values: Masonry Ŕ-Values

Insulation or other Building
Material 9

Ŕ-Value1
Density2
Perm3
Absorption4
Flame
Spread
5

Smoke6
Toxicity7
Aging
Effects & Comments

Brick, common

0.20 30

0.80 40

 
 
 
 
 
 
[30]

Brick, 4″ face

0.44 40

 
 
 
 
 
 
Nil. This is for clay brick.

Brick, 4″ + 1″ reflective air space
 
 
 
 
 
 
 
 

Brick, facing or veneer
0.11 30
 
 
 
 
 
 
 

 
 
 
 
 
 
 
 
 

Concrete Block, two rectangular core, 8″
1.04
 
 
 
 
 
 
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
 
 
 
 
 
 
Filled with lightweight aggregate [30], same warning as above.

Concrete
Block,
 4″
72% solid
(115#/ft3)

1.19

 

 
 
 
 
 
 

Nil

(Also see “Concrete” above)

0.8040 per full thickness

Concrete
Block, 6″
59% solid
1.25
 
 
 
 
 
 
Nil

Concrete
Block, 6″
59% solid
perlite-filled

3.95
 
 
 
 
 
 
 

Concrete
Block, 8″
54% solid
1.45
 
 
 
 
 
 
1.1140 per full thickness

Concrete
Block, 8″
54% solid
perlite-filled

4.65
 
 
 
 
 
 
 

Concrete
Block 10″
52% solid
1.55
 
 
 
 
 
 
Nil

Concrete
Block, 10″
52% solid
perlite filled
5.65
 
 
 
 
 
 
 

Concrete
Block 12″
48% solid
1.65
 
 
 
 
 
 
1.2840 per full thickness

Concrete
Block, 12″
48% solid
perlite-filled
7.05
 
 
 
 
 
 
 

Concrete, poured
0.08 40
 
 
 
 
 
 
 

Notes to the table above

Masonry Ŕ-values Source: adapted from “Sample R-Value Calculations” found at www.maconline.org

Notes:

1. Effects of water intrusion on insulating value and Ŕ-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 Ŕ-value for α 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 Ŕ 2.7) and for an exterior air film (winter, no wind, Ŕ 0.17), an interior air film (again no air movement, Ŕ 0.68), 3/4″ of reflective air space (no convective air movement, R 2.89), 1/2″ drywall (Ŕ 0.45), interior wall cavity insulation (see various fiberglass or other insulating values in this table), to achieve α greater overall Ŕ-value than that afforded by the masonry block or brick wall alone.

3. Presumably the Ŕ-values given are then calcuated for the overall wall structure, averaging the effects of thermal breaks etc. – Ed.

Insulation Values: Particleboard to Plaster

Insulation or other Building
Material 9

Ŕ-Value1
Density2
Perm3
Absorption4
Flame
Spread
5

Smoke6
Toxicity7
Aging
Effects & Comments

Particleboard 5/8″ underlayment, per inch
1.31
 
 
 
 
 
 
5/8″ particleboard underlayment has an Ŕ-value of 0.82 [30]

 
 
 
 
 
 
 
 
 

Perlite insulation
2.5 – 3.720, 30
2-11
High
0
0
0
0
See details at PERLITE INSULATION

 
 
 
 
 
 
 
 
 

Plywood, ?/₵
1.4
 
 
 
 
 
 
Questionable, [need citation]

Plywood, 1/4″
 
 
 
 
 
 
 
Ŕ 0.31 30,40 full thickness

Plywood 3/8″
 
 
 
 
 
 
 
Ŕ 0.47 30,40 full thickness

Plywood 1/2″
 
 
 
 
 
 
 
Ŕ 0.62 – 0.63 30,40 full thickness

Plywood 5/8″ &

Plywood siding 5/8″

 
 
 
 
 
 
 
Ŕ 0.77 30,40 full thickness

Plywood 3/4″

Pywood siding 3/4″

 
 
 
 
 
 
 

Ŕ 0.94 40 full thickness

Ŕ 0.93 40

Phenolic Foam Insulation Ŕ-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 30
 
 
 
 
 
 
 

Insulation Values: Plastic to Polyurethane

Insulation or other Building
Material 9

Ŕ-Value1
Density2
Perm3
Absorption4
Flame
Spread
5

Smoke6
Toxicity7
Aging
Effects & Comments

Plastic, foamed: Home Foam25 low-density
3.921
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
 
 
 
 
 
 
ᑗ-Value 0.53

Polycarbonate film, 6mm
“Greenhouse Plastic”
3. / in ?
0.83 – 0.85 for 6mm
 
 
 
 
 
 
Double layer of 6mm Ŕ = 1.25 to 1.54 (sources vary)

Polycarbonate 16mm Sheet, 5-layer
2.78 33 (not per in)
 
 
 
 
 
 
 

Polycarbonate sheet, 10-wall, 16mm
3.34 34 (not per in)
 
 
 
 
 
 
 

Polycarbonate sheet, 10-wall, 40mm
5.15 34 (not per in)
 
 
 
 
 
 
 

Polyethylene film
(greenhoue glazing)
0.87 32 (not per in)
 
 
 
 
 
 
 

Polyethylene film, 5mm double layer
1.5 32 (not per in)
 
 
 
 
 
 
 

Polyethylene film, 6mm
double layer
1.7 32 (not per in)
 
 
 
 
 
 
 

Polyethylene foam sheets
4.12 / 0.4″ sheet
up to 10.3 / inch
 
 
 
 
 
 
BUBBLE / CLOSED-CELL FOAM SHEETS
Polyethylene foam
321
 
 
 
 
 
 
POLYURETHANE FOAM Spray Building Insulation

Polyisocyanurate Foam Insulation Ŕ-Values

PIR Insulation

Insulation or other Building
Material 9

Ŕ-Value1
Density2
Perm3
Absorption4
Flame
Spread
5

Smoke6
Toxicity7
Aging
Effects & Comments

Polyisocyanurate / Polyurethane panel

PIR panels

5.6 – 7.020
 
 
 
 
 
 
POLYISOCYANURATE FOAM BOARD

Polyisocyanurate foam panel or board, foil faced

6.821 – initial, pentane expanded
7.2040
5.521 – aged 5 to 10 years

 
 
 
 
 
 

Rigid panel insulation board with foil facing both sides, edges exposed

Aged Ŕ-values for foam panels assume aging in-situ for 5-10 years.

Polyisocyanurate foam panel Dow TUFF-Ŕ
6.5 32

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

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 composite insulation
2.8
(5.8-6.2)
2.0
2-3
 
 
 
 

Closed cell

Foil faced21

See POLYISOCYANURATE FOAM and IAQ

Polystyrene Foam Insulation Ŕ-Values

EPS Expanded Polystyrene Insulation (beadboard)

Extruded Polystyrene

XPS Extruded Polystyrene Insulation

Insulation or other Building

Material 9
Ŕ-Value1
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
 
 
 
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); Ŕ-value varies by board density
Also see INSULATION CHOICES

Polystyrene Expanded (XPS) insulation

low-density

3.85
3.9 – 4.420

3.6 – 4.721

 
 
 
 
 
 

See POLYSTYRENE FOAM INSULATION

Also see INSULATION CHOICES

Polystyrene Expanded beadboard
4.040
 
 
 
 
 
 
 

Polystyrene board, extruded expanded high-density (EPS)

Molded

5 – 5.421

4.221

 
 
 
 
 
 
 

Polystyrene board, extruded
540
1.5
1.2-3.0
 
 
 
 

Closed cell

See POLYSTYRENE FOAM INSULATION

Polyisocyanurate / Polyurethane Foam Insulation Ŕ-Values

Insulation or other Building
Material 9

Ŕ-Value1
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
Aged 6.8

2.0
2-3
0
30-50
155-200
CO

Closed cell foam spray insulation;

0-12% shrinkage, Fire safety: may not be left exposed in living area. Initial Ŕ 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 foam insulation rigid panels, foil-faced
7.9 – 8.4
 
 
 
 
 
 
Pentane expanded foam, presence of an air-gap may increase panel performance.
RSI = 45-48

Polyurethane foamed in place
6.2540
 
 
 
 
 
 
 

Polyurethane spray foam 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

Insulation Values: Reflective to Thinsulate

Insulation or other Building
Material 9

Ŕ-Value1
Density2
Perm3
Absorption4
Flame
Spread
5

Smoke6
Toxicity7
Aging
Effects & Comments

Radiant barriers
0 (none)
 
 
 
 
 
 

Blocks radiant heat gain/loss

See RADIANT BARRIERS

Reflective barrier insulation 
0 – 1720
 
 
 
 
 
 

Varies by product. Example:

Reflectix® Ŕ-4.55 down, Ŕ-1.32 up, Ŕ-1.7 horizontal

Reflectix® White side: Ŕ-0.92 down, Ŕ-0.61 up, Ŕ 0.68 horizontal

See REFLECTIVE INSULATION

 
 
 
 
 
 
 
 
 

Rock Wool Batts

Slag wool Batts

3 – 3.8520
 
 
 
 
 
 
See more details at MINERAL WOOL

Rock Wool, Slag wool Loose Fill insulation Ŕ-value

2.5 – 3.720
 
 
 
 
 
 
 

Insulating Values of Roofing Materials

Roofing Material Ŕ-Values

Insulation or other Building
Material 9

Ŕ-Value1
Density2
Perm3
Absorption4
Flame
Spread
5

Smoke6
Toxicity7
Aging
Effects & Comments

Roofing: Asphalt shingles
0.4430,40
 
 
 
 
 
 
 

Roofing: built-up 3/8″ thick plies
0.3330
 
 
 
 
 
 
 

Roofing: wood shingles
0.9430

0.9740
 
 
 
 
 
 

Also see below at “wood”.

The use of this Ŕ-valuye is highly questionable since wood shingle roofs do not block air flow whatsoever.

 
 
 
 
 
 
 
 
 

Sheeps Wool Insulation

3.6 blown-in

4.3 batts

 
 
 
 
 
 
SHEEPS WOOL INSULATION
Silica Aerogel
10
 
 
 
 
 
 
 

Steel siding
 
 
 
 
 
 
 
0.6140 full thickness, hollow-backed

Snow
1
 
 
 
 
 
 
 

Soil or “dirt”
0.25 – 1
0.80 typical at 20% moisture
 
 
 
 
 
 
Depends on soil properties: density, moisture content, moisture movement
See SOIL Ŕ-VALUES
Straw Bale
1.45
 
 
 
 
 
 

STRAW BALE CONSTRUCTION

(Commins 1998) [36]

Stucco, conventional plaster/cement
0.20
 
 
 
 
 
 
[30]

 
 
 
 
 
 
 
 
 

Tectum™ insulated roof panels
2.0
 
 
 
 
 
 
Tectum: α 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

Insulating Values of Building Siding Materials

Building Siding Ŕ-Values

Insulation or other Building
Material 9

Ŕ-Value1
Density2
Perm3
Absorption4
Flame
Spread
5

Smoke6
Toxicity7
Aging
Effects & Comments

Aluminum siding
 
 
 
 
 
 
 
Ŕ 0.6140 full thickness, hollow-backed

Aluminum siding w/ 1/2″ insulating board backer
 
 
 
 
 
 
 
Ŕ 1.8040 full thickness,

Brick veneer 4″
 
 
 
 
 
 
 
Ŕ 0.4440 full thickness

Hardboard siding 1/2″
 
 
 
 
 
 
 
Ŕ 0.3440 full thickness

Logs (solid wood)
1.2540
 
 
 
 
 
 
 

Logs (solid Cedar)
1.3340
 
 
 
 
 
 
Log wall Ŕ-Values vary16

Log slab/board siding
 
 
 
 
 
 
 
see Wood siding / clapboards

Plywood siding 5/8″
 
 
 
 
 
 
 
Ŕ 0.7740 full thickness

Plywood siding 3/4″
 
 
 
 
 
 
 
Ŕ 0.9340 full thickness

Vinyl Siding
0.61
 
Low
0
 
 
 
1/16″ (0.175″)to 3/32″ (0.093″) thick vinyl siding, hollow-backed

Vinyl siding
 
 
 
 
 
 
 
0.6140 full thickness, hollow-backed

?Inul siding w/ 1/2″ insulating board backer
 
 
 
 
 
 
 
1.8040 full thickness

Wood shingle siding, single course

0.8730

 
 
 
 
 
 
 

Wood clapboard siding, 1/2-inch clapboard or shiplap

0.8040

0.8130

 
 
 
 
 
 
 

Urea Formaldehyde UFFI Foam Insulation Ŕ-Values & Properties

Insulation Values: Urea Formaldehude UFFI to Vinyl

Insulation or other Building
Material 9

Ŕ-Value1
Density2
Perm3
Absorption4
Flame
Spread
5

Smoke6
Toxicity7
Aging
Effects & Comments

Urea terapolymer foan
4.4840
 
 
 
 
 
 
 

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

Vacuum Insulated Panels Ŕ-Values

Insulation or other Building

Material 9
Ŕ-Value1
Density2
Perm3
Absorption4
Flame

Spread
5

Smoke6
Toxicity7
Aging

Effects & Comments

Vacuum “insulated” panel
30-50
 
Low
 
 
 
 

Vacuum insulated panels (VIPs) are rigid, air-tight hollow-core panels from which air has been evacuated.

An internal support is needed to keep the panel walls from collapsing when evacuated.

The effectiveness as α vacuum insulating panel will also vary by panel thickness (e.ɢ.ɭ 25mm), as panel walls close together may transer heat by radiation and by the temperatures on the two sides of the panel as radiation transfer of heat increases with the temperture difference.

Vacuum Powder Insulation
25 – 3020
 
 
 
 
 
 
 

Vacum powder insulated panels
20 – 10020
 
 
 
 
 
 
ᑗ.Ş. DOE. Others cite Ŕ-30 – Ŕ-50.


Insulation or other Building

Material 9
Ŕ-Value1
Density2
Perm3
Absorption4
Flame

Spread
5

Smoke6
Toxicity7
Aging

Effects & Comments
VERMICULITE insulation
2.1319, 40 – 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 Ŕ = 2.08
Some sources cite Ŕ = 2.13 – 2.2730

Vinyl Siding
0.61
 
Low
0
 
 
 
1/16″ (0.175″)to 3/32″ (0.093″) thick vinyl siding, hollow-backed

Vinyl siding
 
 
 
 
 
 
 
0.6140 full thickness, hollow-backed

Vinyl Siding, Insulated
2.0
 
 
 
 
 
 

Manufactured with rigid foam plastic insulation laminated to thje siding

ASTM D7793 requires insulated siding to demonstrate α
minimum Ŕ-value of 2.0.

INSULATED VINYL SIDING as HOME INSULATION [PDF] Vinyl Siding Institute

Vinyl Thin Film Window Covering
 
 
Low
0
 
 
 
ᑗ-value and emissivity values vary depending on the type of film, with emissivity values from 0.07 to 0.81 – DeBusk [29]

Water
0.004
 
 
 
 
 
 
The Ŕ-value of water has little practical application but in various discussions is placed around Ŕ 0.004 – effectively almost zero.

Notes on the Ŕ-value of water

  • Water has α specific heat capacity or Ĵ/ kg °₭ of 4200.
  • Choudhary, ʍ. ₭., ₭. ₵. Karki, and Ş. ?. Patankar. “Mathematical modeling of heat transfer, condensation, and capillary flow in porous insulation on a cold pipe.” International Journal of Heat and Mass Transfer 47, no. 26 (2004): 5629-5638.
    Abstract:
    Porous insulation used on pipes carrying cold fluids suffers thermal degradation due to condensation of water vapor and the build up of water in the insulation. … The presence of the wick is shown to significantly reduce the amount of liquid water in the insulation.
  • Endrusick, Thomas ɭ. “Effects of prolonged water contact on the thermal insulation of cold weather footwear.” In Proceedings of the Fifth International Conference on Environmental Ergonomics, Lotens WA and Havenith ₲ (Eds.), pp. 188-9. 1992.
  • Hall JR, John ₣., and Johannes ?. Polte. EFFECTS OF PROLONGED WATER CONTACT ON THE THERMAL
    INSULATION OF COLD WEATHER FOOTWEAR
    [PDF] Journal of applied physiology 8, no. 5 (1956): 539-545.
  • Hallett, Paul ?., Th Baumgartl, and Iain ʍ. Young. “Subcritical water repellency of aggregates from a range of soil management practices.” Soil Science Society of America Journal 65, no. 1 (2001): 184-190.
    Excerpt: An Ŕ value of 10, for instance, would indicate that water repellency accounts
    for α tenfold decrease in sorptivity (ie, the initial wetting rate)
  • Kim, Hyunglok, Michael Н. Cosh, Rajat Bindlish, and Venkataraman Lakshmi. “Field evaluation of portable soil water content sensors in a sandy loam.” Vadose Zone Journal 19, no. 1 (2020): e20033.

Ŕ-Values of Windows

Insulating Ŕ-Values of Windows

Insulation or other Building
Material 9

Ŕ-Value1
Density2
Perm3
Absorption4
Flame
Spread
5

Smoke6
Toxicity7
Aging
Effects & Comments

Windows, single glazed
 
 
 
 
 
 
 
0.9740 full thickness

Single glazed window w/ storm
 
 
 
 
 
 
 
2.0040 full thickness
May vary widely depending on air leaks

Double insulated glass window 3/16″ air space
 
 
 
 
 
 
 
1.6140 full thickness

Double insulated glass window 1/4″ air space
 
 
 
 
 
 
 
1.6940 full thickness

Double insulated glass window 1/2″ air space
 
 
 
 
 
 
 
2.0440 full thickness

Double insulated glass 3/4″ air space
 
 
 
 
 
 
 

2.3840 full thickness

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

Glass w/suspended film
 
 
 
 
 
 
 
2.7740 full thickness

Glass w/ 2 suspended films
 
 
 
 
 
 
 
3.8540 full thickness

Glass w/ 2 suspended films, Low-E
 
 
 
 
 
 
 
4.0540 full thickness

Triple insulated glass 1/4″ air spaces
 
 
 
 
 
 
 
2.5640 full thickness

Triple insulated glass 1/2″ air spaces
 
 
 
 
 
 
 
3.2340 full thickness

Added insulation from tight-fitted drapes, shades, closed-blinds
 
 
 
 
 
 
 
+0.2940

Ŕ-Values of Wood Building Materials

Insulation Values: Wood

Insulation or other Building
Material 9

Ŕ-Value1
Density2
Perm3
Absorption4
Flame
Spread
5

Smoke6
Toxicity7
Aging
Effects & Comments

Wood Ŕ-Values

1.01 – 1.41 (softwoods)
0.71 (hardwoods)

1.2540

 
 
 
 
 
 

The Ŕ-value of wood varies by wood density, species, moisture content.

Ŕ-value of typical 3/4″ thick pine softwood = about Ŕ 1.25
[30]

Wood: 2″ nominal (1 1/2″ actual) 1.8840

Wood 2×4 (1 1/2 Ҳ 3 1/2 actual) 4.3840

Wood 2×6 (1 1/2 Ҳ 5 1/2 actual) 6.8840

Wood Logs & Lumber (Cedar)
1.3340
 
 
 
 
 
 
Log wall Ŕ-Values vary16

Wood door, solid, per inch
1.56
 
 
 
 
 
 
Varies by species, no authoritative source.

Wood Fiber Insulation Batts
1 – 3.4
 
 
 
 
 
 
BALSAM WOOL BATT INSULATION

Wood Fiber Insulation Panels
3.3
 
 
 
 
 
 

WOOD FIBRE INSULATING PANELS

and

SHEATHING, FIBERBOARD – home

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

0.8730

 
 
 
 
 
 
 

Wood siding, 1/2-inch clapboard or shiplap

0.8040

0.8130

 
 
 
 
 
 
 

XPS polystyrene
 
 
 
 
 
 
 
see POLYSTYRENE foam

 
 
 
 
 
 
 
 
 

Notes to the Table of Building Insulation Properties

Because no amount of insulation can keep α drafty building warm, also review ENERGY SAVINGS PRIORITIES. See BLOWER DOORS & AIR INFILTRATION for α 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 Ŕ ᑗ & ₭ VALUE CALCULATION for α guide to calculating heat loss (or gain) rates for buildings and building insulation.

  1. Ŕ-Value is expressed as rate of heat loss per hour per square foot per inch of thickness of material per deg. ₣ – see “R” value definition at Definitions of Ŕ ₭ ᑗ values For some building materials (such as sheet flooring) we give an Ŕ-value for α specfic thickness other than the standard 1″.

    RSI-Values: convert ᑗ.Ş. Ŕ-values to SI units or RSI as follows:  Ŕ-Value / 5.685 = RSI-Value

    Ŕ-1 = 5.678263337 RSI
    or
    RSI-1 = 0.1761101838 Ŕ

  2. Insulation density is expressed in pounds per cubic foot of material
  3. 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.
  4. 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
  5. Flame Spread is α measure of fire resistance of the material. Use these numbers to compare one insulating material to another.
  6. Smoke is α measure of fire safety – that is, the relative amount of smoke produced if the insulation is exposed to flame or combustion
  7. Toxicity is α measure of fire safety – that is, toxins given off if the insulation is exposed to flame or combustion.
  8. 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).
  9. 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.
  10. 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.
  11.  or Thermal conductance of these materials is the reciprocal of the Ŕ-value. ₵ is known only when the ƙ, the thermal conductivity of α material is known. ƙ is the heat transmitted through α 1-inch thickness of homogenous material per square foot per hour when there is 1 degree of temperature change. ƙ= (BTU * inch) / sq.ft. * hour * degF.
  12. Air film: This table of Ŕ-values does not consider the insulating characteristic of the air film on each side of α 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.
  13. 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.
  14. Insects: Exterior foam board on foundations can ease attack by wood destroying insects.
  15. Fire & smoke: Foam insulation products present fire-smoke hazards and usually they must be protected with α fire barrier (usually 1/2″ drywall).
  16. Ŕ-Values for wooden log walls given by the ᑗ.Ş. DOE are in error except for square log walls. ?-logs and round logs that are given α nominal log thickness, say 6″ logs are calculated by DOE as having an R-value of just over 8.

    Watch out

    :
    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 Ŕ-value of α log wall.

  17. Ŕ-Values of uninsulated concrete: Concrete Homes Magazine website search 5/18/2010
  18. Ŕ-Value for concrete, glass, other materials, Wikipedia website search 5/18/2010 citing Ristinen, Robert ?., and Jack Ĵ. Kraushaar. Energy and the Environment. 2nd ed. Hoboken, NJ: John Wiley & Sons, Inc., 2006.
  19. E-Star Colorado. Energy Saving Calculations. Energy Living Alliance, 2008. Web 05/18/2010
  20. ᑗ.Ş. 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, ρ. 24-4, 22-5
    • DOE, Insulation Fact Sheet, Jan. 1988, ρ. 6
    • Journal of Thermal Insulation, 1987, ρ. 81-95
    • ORNL, ORNL/SUB/88-SA835/1, 1990
    • ORNL, Science and Technology for α Sustainable Energy Future, Mar. 1995, ρ. 17
    • ORNL for vacuum insulation panel
  21. Wikipedia, website search 5/18/2010 Ŕ-Values per Inch
  22. EcoHaus UltraTouch cotton insulation batts batts http://www.ecohaus.com/C-121/ultratouch+batts Web search 5/18/2010
  23. Icynene product information see http://www.icynene.com/icynene-insulation/ – Web search 5/18/2010
  24. ICC Legacy Report ER-2833 – Cocoon Thermal and Sound Insulation Products, ICC Evaluation Services, Inc., Website: icc-es.org – Web search 5/18/2010
  25. 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 α zero-ODP4 product. The Saskatchewan Research Council (SRC) advises that even sensitive individuals may take occupancy just 24 hours after application is complete.
  26. Air Krete®, Air Krete Inc., ᴘ.Σ. 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
  27. 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
  28. Nomaco Insulation, “Calculation of K Value and R-Value, Technical Bulletin TS12-0909”, Nomaco Insulation, 3006 Anaconda Rd., Tarboro NC 27886, Tel: 866-876-2684, Website: nomacoinsulation.com, offers this helpful explanation of ₭ values: Quoting:

    The actual k-factor is based on the number of BTUs per hour that pass through α one inch (1”) thick by one
    foot (1’) square section of insulation with α 1°₣ temperature difference between the two surfaces.

    Insulation
    materials usually have k-factors less than one and are
    reported at what is called Mean Temperature. To
    determine the mean temperature, measure the surface te
    mperatures on both sides of the insulation, add them
    together and divide by two.

    When comparing the insulation value of different types of insulation it’s
    important to look at the k-factor AND the mean temper
    ature. As mean temperature rises, the k-factor on
    some insulation materials also increase. – retrieved 3/23/14, original source: http://www.nomacoinsulation.com/pdf/polyolefin%20faq/TS12%200909.pdf

  29. Steve DeBusk, writing on low-e glass vs window films at Buildings.com, retrieved 4/16/2014 original source: , quoting; Low-e window film ᑗ-value and emissivity values can range, depending on the type of film. Standard window films … ᑗ-value and emissivity values vary for standard window films, depending on the type of film, with emissivity values ranging from 0.70 to 0.81,. … Conventional low-e window film has an emissivity rating of 0.33 … there are newer low-e window films available with emissivity ratings as low as 0.07
  30. “Resistance Values of Structural and Finish Materials”, Ira ?. Fulton College, Engineering Faculty, 368 CB, Provo, UT 84602 USA, retrieved 2016/10/25, original source: http://cmfac.groups.et.byu.net/jsmith/Lessons/TempSoundControl/R-Values.pdf

    Watch out

    : this PDF of the heat transfer resistance of strucutral and finish materials may in fact have obtained some of its numbers from our own data at this website page: beware of circular reference citations.

  31. Dow® TUFF-Ŕ™ and Super TUFF_R™ POLYISOCYANURATE INSULATION [PDF] properties, The Dow Chemical Company
    Dow Building Solutions
    200 Larkin
    Midland, MI 48674
    1-866-583-BLUE (2583)
    Fax 1-989-832-1465
    www.dowbuildingsolutions.com retrieved 2020/02/14 original source: http://msdssearch.dow.com/PublishedLiteratureDOWCOM/dh_09a8/0901b803809a8de7.pdf?filepath=styrofoam/pdfs/noreg/179-07932.pdf&fromPage=GetDoc
  32. Awad, Shelly, consultant, Greenhouse glazing options as discussed by greenhousegab.com retrieved 2020/07/07 original source: http://greenhousegab.com/consider-the-r-value/
  33. Charley’s Greenhouse, “16mm Clear Super 5X-Wall Storm Clear Polycarbonate Sheet”, Polycarbonate Store, 17979 State Route 536
    Mount Vernon, WA 98273-3269
    1 (888)-977-POLY [888-977-7659]
    service@polycarbonatestore.com retrieved 2020/07/07 original source: http://www.polycarbonatestore.com/16mm-clear-super-5x-wall-storm-clear-polycarbonate-sheet/
  34. Co-Ex, 10-Wall Polycarbonate Sheet, 16mm/10X E.Ş. with α ᑗ-Value of 1.7W/m2K, [PDF] 5 Alexander Dr., Wallingford, CT 06492 Tel: (203) 679-0500, (800) 888-5364 E-mail: info@co-excorp.com , Website: www.co-excorp.com retrieved 2020/07/07 original source: http://www.co-excorp.com/pdf_files/10X.pdf
  35. Gutex Ŕ-values for Ultratherm 50 given as Ŕ 6.6 for α 1 15/16″ thickness. R-values vary by board thickness. Gutex Ultratherm 160 is 6 5/16″ thick and has an Ŕ-value of 21.5. More on Gutex is at FIBERBOARD SHEATHING
    – source: https://foursevenfive.com/gutex-ultratherm/ retrieved 2020/11/13
  36. Commins, Tav, and Ĵ. E. Christian. “R-value of straw bales lower than previously reported.” California Energy Commission, URL (consulted April 2003): http://www. buildinggreen. com/news/r_value. cfm (1998).
  37. McCULLOUGH, NICHOLAS ?. “Drywall product.” ᑗ.Ş. Patent Application 12/823,542, filed December 29, 2011.
  38. Hassey, Humberto, and ɭ. ɭ. ₵. MagBoard. ROK-ON SteelStud Thermal Analysis [PDF] (2018). VP Engineering MagBoard LLC, e May 2018
    Abstract:
    All wall assemblies use α number of components with varying Rvalue properties. Heat transfer through these materials can significantly impact the overall thermal performance of the walls reducing
    the effective Ŕ-value of the assembly through thermal bridging the
    insulation layers. Effective Ŕ-value of α wall assembly is not just the
    sum of the Ŕ-value of various components due to the fact of thermal
    bridging.
    Metal can be thousands of times better at conducting heat than
    the typical insulating materials found in α wall, therefore the thermal
    bridge incurred by using steel elements can be substantial if no continuous insulation break of the thermal bridge is provided
    ? finite element analysis of the thermal flux properties of α wall
    system using regular batt insulation with the ROK-ON Panel System
    coupled with different gauge 6” steel studs is studied, The effective Ŕ
    values are calculated and shown.
  39. Duton, John E.,, Composite Wall Ŕ-Values, Penn State University, e-Education Institute, College of Earth & Mineal Sciences, retrieved 2021/01/24 original source: https://www.e-education.psu.edu/egee102/node/2064
  40. Ŕ-VALUE of BUILDING MATERIALS [PDF] Alaska Housing Finance Corporation, ᴘ.Σ. Box 101020
    Anchorage, Alaska 99510 USA, Tel: 800-478-2432 Website: https://www.ahfc.us/ retrieved 2021/01/24 original source https://www.ahfc.us/iceimages/manuals/building_manual_ap_1.pdf
  41. Lawton, Mark, Patrick Roppel, David Fookes, ?. Teasdale, and Daniel Schoonhoven. “Real R-value of exterior insulated wall assemblies.” All are with Morrison Hershfield Ltd., Vancouver, BC, Canada (2010).
    Excerpt:
    Batt insulation for installation between studs is manufactured slightly oversized so that
    when it is compressed by the drywall it is possible to avoid even small gaps. In the field,
    air gaps often form at the corners of batt insulation because of defects in installation. This
    common defect can allow significantly more heat flow than the rated Ŕ-value would
    suggest as it allows convective loops to form.

 

Reader ?&? – also see the FAQs series linked-to below

Re-posting from private tin nhắn hộp thư online

Properties of Intumescent paints: Ŕ-values of paint are not meaningful

2020/07/10 Anonymous asked: Ι was curious if you have ever evaluated intumescent paints?

Ι had paid for α study and after taking my money they said they could not do materials under 1 inch in thickness. Ι have patented this material and have been recognized as energy star partner.

Moderator reply:

Ι have not made that study and opine that it'{d} probably be the wrong one to attempt.

The people you paid ought to have known at the outset that α coat of paint is going to be much less than an inch in thickness.

In α general sense as building insulation, paints do not have any useful nor quantifiable “R” value. Intumescent paints do affect the properties of α charred surface, thus reducing fire damage or the rate of fire damage. But good grief, nobody is going to set their building on fire in order to achieve an improvement in “R” value.

Intumescent paints are intended to slow the response of α material to heat in order to improve fire resistance. Examples of pertinent research describe the properties of intumescent coating.

Oliveira, Ŕ. Ɓ. Ŕ. Ş., ?. ɭ. Moreno Junior, and ɭ. ₵. ʍ. Vieira. “Intumescent paint as fire protection coating.” Revista IBRACON de Estruturas e Materiais 10, no. 1 (2017): 220-231.

Junior, Moreno. “Intumescent Paint As Fire Protection Coating.” Revista IBRACON de Estruturas e Materiais (2017).

Otáhal, Ŕ., ?. Veselý, Ĵ. Násadová, ?. Zíma, ᴘ. Němec, and ᴘ. Kalenda. “Intumescent coatings based on an organic‐inorganic hybrid resin and the effect of mineral fibres on fire‐resistant properties of intumescent coatings.” Pigment & Resin Technology (2011).

Excerpt: Findings
It was shown that α silicone‐epoxy hybrid resin is suitable for applications in the field of intumescent coatings. Intumescent coatings based on this resin form α thermally stable thin ceramic‐like layer, which improves the thermal insulation properties of the char. Mineral fibres reinforced the char structure and thus improved fire‐resistant properties of intumescent coating before as well as after the salt spray test. Mineral fibres also improved anticorrosion properties.

Reti, ₵., ʍ. Casetta, Ş. Duquesne, Ş. Bourbigot, and Ŕ. Delobel. “Flammability properties of intumescent PLA including starch and lignin.” Polymers for Advanced Technologies 19, no. 6 (2008): 628-635.

Wang, ɭ. ɭ., У. ₵. Wang, and ₲. ?. Li. “Experimental study of hydrothermal aging effects on insulative properties of intumescent coating for steel elements.” Fire safety journal 55 (2013): 168-181.

?

Thank you for the comment; we have added α number of polycarbonate sheeting Ŕ-values (not per-inch but for various designs, layers, and sheet thickness in mm) from several greenhouse thiết kế sources – now found in the alphabetical Ŕ-value tables above under

Polycarbonate.

Thanks for the suggestion. We welcome your comments or critique. Working together makes us smarter.

You don’t have polycaronate sheeting. ͼ’mon

What would be my over all Ŕ rating for α wall with 1/4″ panel + R 13 insulation + 1/2″ osb + wrap + double 4″ siding?

Sure, Dan, Ŕ 1.14 PER INCH so dividing that by 4 = about Ŕ 0.2

see details at HARDBOARD Ŕ-VALUES https://inspectapedia.com/insulation/Insulation-Values-Table.php#Hardboard

could you tell me the r-value rating of 1/4 inch masonite?

Dave

Ι don’t think that’s α great solution; while α reflective barrier gives some help against heat loss, sand is α pretty good conductor.

Insulation is pretty inexpensive, perhaps not much more expensive than sand. Sand in most areas costs between $300. US and $1000 US per yard – that’s 27 cubic feet, or if we spread it out to 3 1/2″ thick for comparison, that’s roughly 100 sq.ft. thus $3./sqft. (if Ι did the math right)

Fiberglass insulation 3 1/2″ batts cost about $12 to $16. / sq, ft,

Our cottage has solid 2ft thick external walls to two sides of our main bedroom and living room. Ι want to insulate these walls as they are so cold to the touch but Ι don’t have the money to buy off the shelf items, we also don’t want to loose too much space.

Ι have an idea to batten the walls and then after gluing silver foil to the one side of plasterboard screw that to the battens. Ι would leave α gap at the top of the board to pour dry sand between the battens to fill the gap behind the boards.

Does any of this make sense to you, would it be worthwhile? Together with this in the bedroom we are filling the floor rafter space with insulation and putting sheet boarding over the floorboards.

Mick

To have room for α detailed reply Ι repeat your question and answer it near the end of the article above on this page. Please take α look and let me know if you have more questions.

What would be the percentage of heat loss reduction if we add an Ŕ 18 to an Ŕ 3 roof.

Question: what is the percent heat loss reduction when we increase Ŕ-Value

2019/12/05 Mick Noteboom said:

What would be the percentage of heat loss reduction if we add an Ŕ 18 to an Ŕ 3 roof.

Reply:

Thanks for an interesting question, Mick. Ι offer two different answers:

1. Calculate percent improvement in Ŕ-Value:

R3 + R18 = R21 total Roof Ŕ-Value. Ι calculate insulation resistance to heat loss or “R” percentage improvement always as relative to the original number.

The increase = R21 – R3 = exactly 18 – the value by which you are increasing the Ŕ-value.

The percentage increase ( % increase ) = Increase ÷ Original Number × 100.

18 / 3 = 6 Ҳ 100 = 600% increase in Ŕ-value.

However moving right along to viewpoint #2

Watch out: in my opinion increasing Ŕ-value to reduce the rate of heat loss in α roof is entirely and only theoretical. The actual change in rate of heat loss through the roof will be (most-likely) α lower percentage as heat loss is affected by

  • Heat transmission by conduction or transmission (ᑗ-Values) through framing (rafters) which interrupt the insulating blanket (for α roof insulated between rafters).

At HEAT LOSS Ŕ ᑗ & ₭ VALUE CALCULATION we note that

The heat loss by conduction to the building exterior is not α fixed rate. Rather the heat loss rate increases exponentially as the temperature difference between indoors and outdoors increases. The greater the temperature difference across the roof the greater the rate of heat loss. Higher temperatures indoors OR lower temperatures outdoors increase the rate heat loss through conduction.

ᑗ-values measure the thermal transmittance of heat in or out of α building and combines heat movement by all principles that are occurring at α building: radiation, convection, and conduction.

So you can see that “U” values are more complex but really more complete than “R” values.

  • Heat loss through air leaks or exfiltration or infiltration. The more air leakage there is the greater the rate of heat loss.

Both of those factors mean that α 600% improvement in or reduction in heat loss rate by improved Ŕ-value will not be likely to give an actual 600% net improvement.

The most-insulated roof structure I’ve built combined insulation of the space between rafters with α layer of high-Ŕ foil-faced foam board on the underside of the rafters. This latter detail reduce the conduction losses and also allowed us to assure that there was no air leakage into the roof cavity (this was α cathedral ceiling roof).

It is helpful to understand Ŕ-value, ₭-value, and ᑗ-value as various ways of describing heat loss or gain.

We define Ŕ-values at Ŕ-VALUE inspectapedia.com/heat/HVAC_Definitions.php#ŔValue

Ŕ values and heat loss: The “R” value of α material is its resistance to heat flow through the material. When buying various insulation materials you will almost always see an “R” value quoted for the material. In general, higher “R” means more resistance to heat loss and therefore lower heating or cooling bills for the building.

Mathematically, “R” is simply the reciprocal of the two measures discussed in more detail below:

ᑗ – the measure of heat transfer (the ability of α substance to conduct heat) discussed above and also at “U”

₭ – the coefficient of heat transmission discussed at “K”

“K” (Ŕ = 1/₭)

or

“U” ( Ŕ(whole building) = 1/ᑗ)

Heat transfer rates through α roof (or walls or floors) are usually calculated and expressed in ᑗ-Values – detailed at ᑗ-VALUE inspectapedia.com/heat/HVAC_Definitions.php#ᑗValue

where we define ᑗ-Values:

ᑗ-value measures the ability to transfer heat, an inverse condition, to heat movement resistance, or in other words, or ᑗ-value measures the ability of α substance to allow the transfer of heat

Bottom line: find and fix un-wanted air leaks from the occupied space into the attic or into the roof cavity.

More scary heat loss calculations:

Fourier’s Law gives us the rate of heat loss through conduction:

? = ᑗ Ҳ ? Ҳ ΔT

where

= thermal conductance, BTU / (ft2) (Fº)(hr)

? = surface area of object, ft2

ΔT = temperature difference (T1 -T2), Fº

So you can actually calculate “U” for your specific roof, but with the warnings Ι gave that this is still only theoretical since the true heat loss or gain is affected by air leaks and other factors.

Question: calculate the Ŕ-rating of α wall assembly

2019/11/04 Anonymous said:

What is the Ŕ rating of α wall with 1/2” lap siding over 3/4” shiplap on α 2×4 wall with 3/4” ship lap on the inside?

Reply:

Anon

We need to add up all of the wall components (and of course we’re ignoring any effects of air leakage)

If your wood siding is plywood you can see Ŕ-values in the table above

at PLYWOOD Ŕ VALUES

With α 2×4 wall you have 3 1/2″ in the wall cavity that can be insulated. What’s in your wall? Air, fiberglass, something else?

We cannot calculate the Ŕ-value of α wall assembly until we know the complete list of all of the components that comprise the wall, and their individual dimensions and also the actual wall construction and dimensions including where there are air spaces.

Watch out: it’s also α little dangerous to just add up the Ŕ-value of the wall components to claim you then know the wall’s resistance to heat loss. For example, to those Ŕ-values Ι would add the value of air spaces in the construction but Ι would deduct for those same air spaces if they are not sealed and protected from in-wall-cavity convection currents that can actually pump heat between the hot and cold side of such α wall.

Air leakage in α wall construction can also quickly overcome any advantage of the wall’s insulating value.

Continue reading at HEAT LOSS Ŕ ᑗ & ₭ VALUE CALCULATION or select α topic from the closely-related articles below, or see the complete ARTICLE INDEX.

Or see INSULATION Ŕ-VALUES & PROPERTIES FAQs – questions & answers posted originally at this page.

Or see these

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INSULATION Ŕ-VALUES & PROPERTIES at InspectApedia.com – online encyclopedia of building & environmental inspection, testing, diagnosis, repair, & problem prevention advice.

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INDEX to RELATED ARTICLES: ARTICLE INDEX to BUILDING INSULATION

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