R-Values of Common Building Materials!

The R-value of a material determines how quickly heat is conducted across it. The values below are some of the more common R-factors for surfaces found on buildings in the U.S.

Exterior Walls with Siding
Exterior Walls with Siding Concrete block (8")R-Value
Concrete block (8")2
with foam insulated cores20
with 4" on unisulated stud wall4.3
with 4" insulated stud wall14
Brick (4")R-Value
with 4" uninsulated stud wall4
with 4" insulated stud wall14
Wooden FrameR-Value
Uninsulated with 2" x 4" construction4.6
with 1 1/2" fiberglass9
with 3 1/2" fiberglass; studs 16" o.c. 12
with 3 1/2" fiberglass and 1" foam20
StrongGreen™ Structural PanelR-Value
3 1/2" thick polyurethane panel X 24" Wide27
6" thick polyurethane panel45
3 1/2" thick polyurethane panel w/ceramic coating47
6" thick polyurethane panel W/ceramic coating65
Floor
Floor Over unheated basement or crawl space vented to outsideR-Value
Uninsulated floor4.3
6" fiberglass floor insulation25
Over sealed, unheated, completely underground basementR-Value
Uninsulated floor8
with 1" foam on basement walls19
with 3 1/2 fiberglass on basement walls20
Insulated floor, 6" fiberglass43
Concrete SlabR-Value
No insulation11
1" foam perimeter insulation46
2" foam perimeter insulation65
StrongGreen™ Structural PanelR-Value
3 1/2" thick polyurethane panel X 24" Wide27
6" thick polyurethane panel45
3 1/2" thick polyurethane panel w/ceramic coating47
6" thick polyurethane panel W/ceramic coating65

                   

Exterior Doors
(Excluding sliding glass doors)
Calculate glass area of door as window
Wood DoorR-Value
1 1/2" no storm door2.7
1 1/2" with 1" storm door4.3
1 2/3" solid core door3.1
Steel with Foam Core DoorR-Value
1 3/4" Pella13
3/4" Therma-Tru16
Roof / Ceiling
MaterialR-Value
No Insulation3.3
3 1/2" fiberglass13
6" fiberglass20
6" cellulose23
3 1/2" thick polyurethane panel X 24" Wide27
12" fiberglass 43
6" thick polyurethane panel X 24" Wide45
12" cellulose 46
3 1/2" thick polyurethane panel w/ceramic coating47
14" cellulose 54
6" thick polyurethane panel W/ceramic coating65
















 

GlassR-ValueLow EmissivityDrapesQuilts
Single pane0.91.11.43.2
Single w/storm window22.54.2
Double pane, 1/4" air space1.7 2.24
1/2" air space22.992.54.3
Triple pane, 1/4" air space2.634.8

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