Ross Baran, Architectural Design Support Rep., explains the differences between R-value, U-value, and U-factor, plus how these values affect a door’s thermal performance.
When it comes to insulated doors, there’s a lot of talk about. R-value, U-value, and U-factor. If you’re having trouble wrapping your head around these concepts, you’re not the only one who feels left out in the cold.
Here's a super easy way to warm up to these thermal performance metrics.
R-value and U-value
We’ll start with values R-value and U-value.
Think of this jacket as an insulating door.
There it is, just hanging there. The jacket, by itself, represents R-value. R-value is the estimated value of how one door part, or in this case, the jacket, can resist heat flow.
Then there’s U-value. U-value focuses on heat transfer, or how quickly you get cold in the jacket when you’re standing out in the elements.
Technically speaking, U-value is the inverse of R-value. That really means it’s the same thing, just expressed differently. It shows the calculation of the rate of thermal transfer through that single point of the door, or jacket, as the case may be.
But here’s the kicker: U-value doesn’t include what else you’re wearing.
So the U-value stays the same even if you’re not wearing a hat, gloves, or boots.
That being said, you might as well be wearing flip-flops and shorts with the jacket when you’re out in a blizzard. Because U-value is all about the jacket, and only, the jacket.
U-factor
Now, let’s talk about U-Factor.
Here’s a great way to remember this:
U-factor factors in everything you’re wearing when you’re outside, not just the jacket, but the hat, gloves, and boots, your entire outfit, head to toe. When thinking in terms of the insulated door, U-factor is the tested rate of heat transfer of the entire door assembly including the bottom bar, slats, guides, etc. If your insulated door has a low U-factor, you can count on exceptional thermal performance and optimal energy efficiency.
Connect with our Architectural Design Team
Feel free to reach out to the Architectural Design Team for help with drawings and specifications on your insulated door. We can also assist you with specifying the correct product for your application.
