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: 429

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

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

angela hines replied to Alan Gindt's discussion Minneapolis Blower Door, Pressure Pan, and Bacharach CO 3 For Sale in the group Energy Auditing Equipment for Sale, Trade or to Purchase
"What is the price for them together? What is the price just for the blower door set?"
16 hours ago
Alan Gindt replied to Alan Gindt's discussion Minneapolis Blower Door, Pressure Pan, and Bacharach CO 3 For Sale in the group Energy Auditing Equipment for Sale, Trade or to Purchase
"Yes"
16 hours ago
Profile IconKevin Love, Shannon Kahl and Lauren McNutt joined Home Energy Pros
17 hours ago
Anna Jursik's blog post was featured
18 hours ago
Everblue posted a status
"New Energy Auditor Jobs posted on our Massachusetts Job Board! Check them out: http://www.everblue.edu/hiring/job-board/massachusetts"
19 hours ago
Everblue posted events
20 hours ago
angela hines replied to Brooke Ingram's discussion 3 full sets of testing equipment available for sale! in the group Energy Auditing Equipment for Sale, Trade or to Purchase
"Hi is the Minneapolis blower door set still available?"
20 hours ago
angela hines replied to David Allen's discussion Like new! Great Deal! Minneapolis Blower Door system, Duct Blaster and Flir i-7 Infrared Camera for sale in the group Energy Auditing Equipment for Sale, Trade or to Purchase
"I am interested in the blower door and camera. Are they still available? If so i will buy. Please…"
21 hours ago
angela hines replied to Alan Gindt's discussion Minneapolis Blower Door, Pressure Pan, and Bacharach CO 3 For Sale in the group Energy Auditing Equipment for Sale, Trade or to Purchase
"Is this still for sale? I am interested and would want to buy."
21 hours ago
angela hines joined allen p tanner's group
Thumbnail

Energy Auditing Equipment for Sale, Trade or to Purchase

Discuss the pros and cons of the equipment you are interested in prior to purchase. Post equipment…See More
21 hours ago
Anna Jursik posted a blog post
21 hours ago
Tom Mallard replied to Kaushal Bharath Raju's discussion Affordability & Deep Energy Upgrade/Passive House Retrofit in Berkeley, California.
"After seeing the cost estimates by Glenn, my addition of insulation board under the siding on a…"
yesterday

© 2014   Created by Lawrence Berkeley National Laboratory.

Badges  |  Report an Issue  |  Terms of Service