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: 2636

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

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 May 31, 2013. 4 Replies

Infrared Image - What is it?

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

Timber Home with no effective air barrier

Started by Davide Lanzoni. Last reply by Sean Lintow Sr Apr 11, 2012. 1 Reply

Videos

  • Add Videos
  • View All

Latest Activity

Steve posted a discussion

Too many BTU's. Too much horsepower?

I have a 20 year old house with a 2 1/2 ton A/C for the lower floor and a 1 1/2 ton A/C for the…See More
3 hours ago
Profile IconSteve, Beth Edwards, Derrick Brodanex and 1 more joined Home Energy Pros
4 hours ago
Jill Lindman posted an event

High Performance Mechanicals for Houses That Work at Tacoma Power

May 25, 2017 from 8:30am to 4:30pm
High Performance Mechanical Systems for Houses That Work is a mid-level, full day seminar geared…See More
4 hours ago
Home Energy Magazine posted videos
6 hours ago
Diane Chojnowski posted events
23 hours ago
Richard Drohan liked eric anderson's discussion Energy auditing equipment for sale
yesterday
Richard Drohan replied to Jeffrey Anthony's discussion Blower Door Kits in the group Energy Auditing Equipment for Sale, Trade or to Purchase
"Please send pictures to rickdrohan@gmail.com.  thanks"
yesterday
Richard Drohan 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
yesterday

Home Energy Pros

Welcome to Home Energy Pros – the unique digital community by and for those who work in the home energy performance arena.

Home Energy Pros was founded by the developers of Home Energy Saver Pro (supported by the U.S. Department of Energy) and brought to you in partnership with Home Energy magazine.  Home Energy Pros is sponsored by the Better Buildings Residential Network. Please honor our Guidelines

© 2017   Created by Lawrence Berkeley National Laboratory.   Powered by

Badges  |  Report an Issue  |  Terms of Service