... with windows with a better R-value than walls ?

http://www.good.is/post/thermogram-shows-the-extreme-efficiency-of-...

--- i'm skeptical...

 

 

Views: 187

Replies to This Discussion

You should be skeptical, Davide!! Something is clearly not right. Windows are about 20% reflective but all of them at that angle could be reflecting the same cold sky.

 

I think the interior temperatures of the buildings were different. I have R=10 windows and even they are warmer than my R=45 walls!


As the image below shows, we can make windows appear pretty much an...
 Interior temps in this image were all the same; the difference is what is being reflected, cold sky (top), warm surroundings (bottom) or a mixed background (middle).

Here is another image showing R=10 windows (Serious brand) on the right and conventional double-glazed, nitrogen-filled windows on the left (there is a screen on the right window of these). Interior temperatures are identical in both rooms.

John

Is the emissivity difference between the glass and the wall making a difference too?

Ed Minch

It is certainly possible as I no longer have the exact specs for the older windows. My belief, however, is that exterior surfaces of both old and new glazings are uncoated so what we are seeing is related only to the difference in actual heat transfer.

For the other image (3 windows stacked), all three windows are identical. The difference in "apparent temperature" is entirely due to differences in the reflected background temperatures.

RSS

Home Energy Pros

Home Energy Pros was founded by the developers of Home Energy Saver Pro (sponsored by the U.S. Department of Energy,) and brought to you in partnership with Home Energy magazine.

Latest Activity

Bob Blanchette replied to Hal Skinner's discussion Any success getting landlords to energy upgrade a single family rental unit?
"The landlords don't want the improvements done even if they don't have to pay for it?…"
19 hours ago
Hal Skinner posted a discussion
19 hours ago
Hal Skinner replied to Hal Skinner's discussion Any success getting landlords to energy upgrade a single family rental unit?
"Hi Bob, The tenants all say they cant do anything to the building.  We would get referred…"
21 hours ago
Tom White commented on Tom White's video
Thumbnail

The Future of Housing - And How Airtightness Can Help

"Ben's Kickstarter documentary, The Future of Housing, was fully funded. The grand premiere…"
yesterday
Tom White's video was featured

Simon Sinek: How great leaders inspire action

TED Talks Simon Sinek has a simple but powerful model for inspirational leadership all starting with a golden circle and the question "Why?"
yesterday
peter chang's discussion was featured

Programmable tstat for electric baseboard?

Ok, just want to throw this out there. I live in the high desert, 6800' or so. My house is pretty…See More
yesterday
Tom White posted a video

Simon Sinek: How great leaders inspire action | Video on TED.com

TED Talks Simon Sinek has a simple but powerful model for inspirational leadership all starting with a golden circle and the question "Why?" His examples include Apple, Martin Luther King, and the Wright brothers ... (Filmed at TEDxPugetSound.)
yesterday
Michael Dunseith posted a photo
yesterday

© 2014   Created by Lawrence Berkeley National Laboratory.

Badges  |  Report an Issue  |  Terms of Service