Sectional Door Insulation Ratings
U-factor & R-value of Garage Door Insulation
The U-factor measures the rate at which heat is transferred through a material, such as a garage door. A lower U-factor indicates better insulation, meaning the residential garage or commercial sectional door will resist heat flow more effectively. The R-value evaluates the thermal resistance of a sectional door. It represents how well the door can impede the flow of heat. The higher the R-value, the greater the insulation capability of the door. U-factor is not the reciprocal for R-value for residential garage or commercial sectional doors. The biggest difference between R-value and U-factor ratings is how they are measured. R-value ratings are calculated mathematically by measuring a single section of a garage or commercial sectional door. U-factor ratings, on the other hand, are calculated by measuring the whole door system installed (the entire door, siding, framing, wall, materials used, etc.). This gives a more accurate thermal transference rating and as such, a more accurate picture of the thermal insulation efficiency.
Another reason for the move to U-factor, is that it is difficult to accurately measure the R-value of a section of a panel that is not completely flat(i.e. panels that have grooves or indentations cannot be accurately tested with R-value). U-factor gives a more accurate rating of the entire door, while R-value only measures a section of a single panel.
Is U-value the same as U-factor? U-value is used differently across the building and manufacturing industry, in some instances being introduced as the reciprocal of R-value. Only U-factor is used in the building codes for door and windows. Therefore, Overhead Door™ Brand will remove all U-value listings. This will remove any confusion regarding the meaning of U-value for the residential garage and commercial door industry and further emphasize the integrity of U-factor certified ratings.
Overhead Door Corporation Participates in the Door & Access Systems Manufacturing Association(DASMA) Thermal Performance Verification Program. The program verifies the thermal performance of residential sectional garage doors and commercial sectional doors
What is the standard U-factor/R-value for a garage door?
Below is a list of our garage and commercial doors and the U-factor/R-value of each one.
Traditional Steel Model 1600
|
Polystyrene
|
.23
|
9.8
|
|
Insulated Steel-Back - Model 470
|
Polyurethane
|
.23
|
9.83
|
Durafirm Collection Model 3560
|
Polyurethane
|
.24
|
11.75
|
Thermacore Sectional Steel - Model 591
|
Polyurethane
|
.13
|
14.86
|
Thermacore Model 5720
|
Polyurethane
|
.20
|
9.31
|
Thermacore Sectional Steel - Model 592
|
Polyurethane
|
.10
|
17.5
|
Thermacore Model 5740
|
Polyurethane
|
.15
|
12.76
|
Thermacore Sectional Steel - Model 593
|
Polyurethane
|
.15
|
12.76
|
Thermacore Windload Model 5745
|
Polyurethane
|
.15
|
12.12
|
Thermacore Sectional Steel - Model 594
|
Polyurethane
|
.15
|
12.76
|
Thermacore Model 5760
|
Polyurethane
|
.10
|
17.5
|
Thermacore Sectional Steel - Model 596
|
Polyurethane
|
.10
|
17.4
|
Thermacore Windload Model 5765
|
Polyurethane
|
.12
|
16.22
|
Thermacore Sectional Steel - Model 598
|
Polyurethane
|
.20
|
9.31
|
Impression Steel Model
|
Polyurethane
|
.18
|
12
|
Thermacore Sectional Steel - Model 599
|
Polyurethane
|
.10
|
17.5 |
Courtyard Collection
|
Polyurethane
|
.20
|
9.3
|
Thermacore Sectional Steel - Model 850
|
Polyurethane
|
.07
|
26 |
Carriage House
|
Polyurethane
|
.16
|
10
|
Sectional Steel Windload - Model 515
|
Polyurethane
|
.15
|
16.12 |
Courtyard
|
Polyurethane
|
.15
|
12.76
|
Sectional Steel Windload - Model 525
|
Polyurethane
|
.12
|
16.22 |
Courtyard Windload
|
Polyurethane
|
.15
|
12.12
|
Aluminum Full View Insulated Glass - Model 521
|
Insulated Glass
|
.30
|
2.6 |
Impression Fiberglass
|
Polyurethane
|
.15
|
7.6
|
Aluminum Full View Low-E Insulated Glass - Model 521
|
Low E Insulated Glass
|
.28
|
3.43 |
Aluminum Full-View
|
Insulated Glass
|
.30
|
0
|
|
|
|
|
Aluminum Full-View
|
Low E Insulated Glass
|
.28
|
0
|
|
|
|
|
*U-factor values are independently tested and verified per ANSI/DASMA 105.
**Overhead Door uses a calculated door section R-value for our insulated doors.