Hi everyone,

   I am new at understanding how to read an infrared camera. I want to see what a wall looks like with or without insulation. Here's my question:

Does there need to be a temperture difference from the inside of the house  to the outside to see if there is insulation in the walls?

What should that difference be? ie 15 degrees.

Do you ask the homeowner to turn up the heat in the winter or turn on the A/C in the summer.

How best do I find out if there is insulation in those walls?

Thanks for your comments

Judi Lyall w/ SHE BUILDS GREEN

Views: 2980

Replies to This Discussion

Thanks John, i appreciate you taking the time to answer my quirey. do you know what the indoor ambient temperature was at the time of the photo? thanks again for helping me understand.

Dale,

I looked up the BD test.  At the start of the Blower Door the inside was 70 and the outside was 43.  From what I remember, the outside didn't change much all day.

Judy

An important thing to remember is that the delta T (temperature difference) that's needed refers to "surface" to "surface" differences when investigation insulation issues.  Ambient temperatures can be a little misleading sometimes when we are investigating energy transmission issues.  For example, If the interior has a surface temperature of 70F and the exterior ambient is 30F we would think that the heat would move from inside to outside (2nd law of thermodynamics - hot to cold).  But what if you are looking (from the inside) at a south wall that has been effected by the sun for a few hours?  That wall might be 120F.  Now the heat movement is from outside to inside.  Missing insulation would look warm from the inside.  And if you go over and look at a north wall, which is not effected by the sun, missing insulation would look cool.  So, I always ask myself: What's the direction of the heat movement surface to surface, inside to outside or outside to inside?  And then I identify the color of the path of least resistance.  The framing members should be the path of least resistance in a fully insulated wall.  If insulation is compromised or missing then it will show as the path of least resistance.   That being said, air leaks usually require much less of a temperature differential, maybe only 3 degrees F and that is ambient to ambient, not surface to surface.  The sensitivity of the camera detector system can certainly have a positive or negative effect on the delta T needed in both scenarios.

RSS

Discussion Forum

Having some fun with our cameras

Started by Mike Pagozalski. Last reply by Mike Pagozalski Jul 31. 2 Replies

Expert Eye Needed

Started by Matthew P. Last reply by Ed Minch Nov 15, 2014. 17 Replies

Google Thermal View?

Started by Joshua Knittel. Last reply by tedkidd Jun 1, 2013. 4 Replies

Infrared Image - What is it?

Started by Fluke Thermal Imaging. Last reply by Dale Sherman Apr 26, 2012. 6 Replies

Latest Activity

John Hatfield replied to David Butler's discussion How would you insulate this roof?
"David I think the finish edge application is critical but several un-knows exist. Such as how far…"
8 hours ago
David Butler replied to David Butler's discussion How would you insulate this roof?
"@Kevin, that article is behind a pay wall. Here's the original posted on Allison's…"
9 hours ago
Kevin Miller replied to David Butler's discussion How would you insulate this roof?
"Good question.  I don't know the answer.   I'd love to know whether there…"
9 hours ago
David Butler replied to David Butler's discussion How would you insulate this roof?
"Hi John, thanks for pointing out my faux pas: I made clear in my original post that rainwater…"
9 hours ago
John Hatfield replied to David Butler's discussion How would you insulate this roof?
"Kevin, Is the "Kool Seal" product certified for potable water collection?"
9 hours ago
Mike Berg joined Tom White's group
Thumbnail

Weatherization

Share your concerns and successes as a weatherization professional, or information for this…See More
9 hours ago
Profile IconBlake Reid, James Barras, Kathleen ODonnell and 5 more joined Home Energy Pros Forum
9 hours ago
Jon Finewood joined Diane Chojnowski's group
Thumbnail

Job Board

This group is for posting jobs related to all aspects of the home performance industry including…See More
10 hours ago

Photos

Loading…
  • Add Photos
  • View All

© 2017   Created by Home Performance Coalition (HPC)   Powered by

Badges  |  Report an Issue  |  Terms of Service