New Tech Note: Top Ten Myths About Thermal Imaging Cameras

[ltack]

We have just published a new tech note: "Top Ten Myths About Infrared Thermal Imaging Cameras". This 10 page presentation should be of great use to people buying their first TI camera.

http://www.pembrokeinstruments.com/_download_pdf_897/_Pembroke-PDF-Downloads/Top-Ten-Myths-IR-Thermal-Cameras-Pembroke.pdf

Les

http://pembrokeinstruments.com

[Jason Kaylor]

You know what is weird is that FLIR produces a 12 things to look for in an infrared camera, and yours and theirs are not the same. Weird how two different sources come up with 22 combined different things.

JJ

[Jason Kaylor]

Originally Posted by ltack

We have just published a new tech note: "Top Ten Myths About Infrared Thermal Imaging Cameras". This 10 page presentation should be of great use to people buying their first TI camera.

http://www.pembrokeinstruments.com/_download_pdf_897/_Pembroke-PDF-Downloads/Top-Ten-Myths-IR-Thermal-Cameras-Pembroke.pdf

Les

http://pembrokeinstruments.com

Any reason you did not put the Fluke Ti32 (same price as the TiR32) in your brochure? lol.

Also fix your temperature range on the TiR32. I find it better to make sure my stats are correct before I publish stuff like this.

JJ

[Jason Kaylor]

Misc quotes from the PDF:

"The greater the thermal sensitivity a camera has, the better it will work for my thermal applications. FALSE"

Really? You might want to be more exact on what applications you are referring to. If you get a call from someone wanting to watch the thermal patterns of a bunch of soy bean plants to see which is engineered better, you are telling me the thermal sensitivity doesn't matter?

Thermal imaging cameras should never be used in the daylight. FALSE

Weird because I am almost sure that if you are doing a flat roof inspection with shadows on the roof, it is going to be basically impossible to do a scan properly.



JJ

[John McKenna]

THREE: The color of the target will impact thermal measurements. FALSE

Dark colors can be warmer in sunlight than lighter colors.
Light colors can be cooler in sunlight and some are more reflective.



FOUR: Thermal imaging cameras should never be used in the daylight. FALSE

Sunlight (UV radiation) can influence the surface materials being scanned, and
make it more difficult to see things that could have been seen before the UV rays
heated those materials.

[James H. Bushart]

The bottom line is this:

A thermal image of a ceiling, by itself, is as good at informing you about the effectiveness of the attic insulation as shining a flashlight on an air return vent will tell you about the effectiveness of the heat pump.

[John McKenna]

Originally Posted by jbushart

The bottom line is this:

A thermal image of a ceiling, by itself, is as good at informing you about the effectiveness of the attic insulation as shining a flashlight on an air return vent will tell you about the effectiveness of the heat pump.

I don't think so...

[James H. Bushart]

Meaningless.

Many guys point their cameras looking for missing insulation and think that they have saved the consumer money when they spot things like you just did. Big deal.

Second to fenestration, the biggest losses of energy occur from air leaks through the ceiling....and to an air leak, insulation is nothing but an "air filter" for the air as it leaves the building.

Then, while your camera shows areas that are presumably insulated....it fails to note the fact that the insulation has been smashed into place or otherwise flattened, or fails to be flush with every edge, or is bent to make it fit....which can reduce its R-value by up to 50%. None of that shows up in your picture which makes your picture, at best, misleading.

[ldapkus]

Originally Posted by jbushart

Meaningless.

Many guys point their cameras looking for missing insulation and think that they have saved the consumer money when they spot things like you just did. Big deal.

Second to fenestration, the biggest losses of energy occur from air leaks through the ceiling....and to an air leak, insulation is nothing but an "air filter" for the air as it leaves the building.

Then, while your camera shows areas that are presumably insulated....it fails to note the fact that the insulation has been smashed into place or otherwise flattened, or fails to be flush with every edge, or is bent to make it fit....which can reduce its R-value by up to 50%. None of that shows up in your picture which makes your picture, at best, misleading.

Just weeks ago you were a critic of IR technology, now after the purchase of an IR camera, a blower door and a certification course you're a pro.....un f u c k i n g believable!!!!!!

[John McKenna]

Originally Posted by jbushart

Meaningless.

Many guys point their cameras looking for missing insulation and think that they have saved the consumer money when they spot things like you just did. Big deal.

Second to fenestration, the biggest losses of energy occur from air leaks through the ceiling....and to an air leak, insulation is nothing but an "air filter" for the air as it leaves the building.

Then, while your camera shows areas that are presumably insulated....it fails to note the fact that the insulation has been smashed into place or otherwise flattened, or fails to be flush with every edge, or is bent to make it fit....which can reduce its R-value by up to 50%. None of that shows up in your picture which makes your picture, at best, misleading.

Incorrect.

1- Insulation deficiencies in the ceiling are a significant issue. (try
reporting that you did not inspect the ceiling insulation because it
is meaningless... LOL).

2- Air leaks are bad, but even without air leaks, the insulation
deficiency is still a real issue (btw... thermal imaging can reveal air
leaks as well - to the trained thermographer).

3- Thermal imaging can easily reveal insulation deficiencies, even
after a RESNET and BPI inspector passed the house (the naked eye
cannot see the things IR reveals). These issues can be caused by
the insulation being smashed into place or otherwise flattened, or
fails to be flush with every edge, or is bent, or even more reasons.

Smashed insulation has one signature. Air gaps around the edges
of insulation has another signature. The IR camera can many times
see these distinctions. A visual inspection will miss these issues
many times, but IR can see it very easily. An energy auditor
without an IR camera is 50% blind.

Since you have never been trained or used an IR camera, then you
don't know these things.

You stated one time that unless the interior and exterior temperature
are exactly the same, thermal imaging would not work well. Do
you still proclaim this error? Any trained thermographer will tell you
that this condition is exactly the environment to avoid and is called
by the term "low delta T".

The above comments are "infrared 101".

[James H. Bushart]

You sell training and cameras and gain, financially, from your unsubstantiated claims.

I am not "incorrect". You are, and for obvious reasons.

If you do not own and use a blower door, you cannot quantify air leaks...nor are you able to safely recommend mitigation. If you were properly trained, you would know this.

[Jason Kaylor]

Originally Posted by jbushart

Second to fenestration, the biggest losses of energy occur from air leaks through the ceiling...

According to a Resnet study, both of those statements are incorrect. The number one cost to consumers when associated with energy (heating/cooling) loss is via the ducts.

If armed with that information you are mostly correct. Using IR for the ducts is mainly pointless due to line of sight and emissivity issues associated with duct work.

In my opinion you are throwing out a couple of considerations to the benefits of IR. In your example you want to crawl up in the attic and do a visual of all the insulation. At the end of the day, you are correct, you will find all the same issues that you did with IR. First, how long will that take you vs IR? Second, is your process non evasive (you will be moving and compacting insulation as you move around)? Where fiberglass exists do you really want to be crawling and breathing that? What about an attic with asbestos, same questions, plus the legality of even messing around up there is a concern. Finally I would invite you to come to AZ and crawl around in attics all day long during the summer doing this while an IR inspector is down in the AC doing the same job. There are a few others like line of sight with your flashlight, tight areas etc.

IR is just a tool, like any tool it has its time and place. You are 100% correct, IMO, that using it solely is not a means to the end. However, when used in conjunction with other tools, experience and in the hands of someone with a background in what they are pointing the camera at, IR can find and isolate issues that would otherwise potentially not be found or properly diagnosed.

Personally, in your example, I use IR, and a blower door, to isolate the issue and then still end up in that hot attic with the flash light and all the aforementioned issues to deal with anyway. The good news is I can limit my time up there and provide the consumer with additional qualitative information (my flash light will not show the 10 degree delta T that John's camera showed).

JJ

[David A. Andersen]

Originally Posted by jbushart

The bottom line is this:

A thermal image of a ceiling, by itself, is as good at informing you about the effectiveness of the attic insulation as shining a flashlight on an air return vent will tell you about the effectiveness of the heat pump.

Not!

Well, maybe. What do you mean "by itself"?
Is this a leading statement?

You can't get the R-Value with just one click of the camera, if that is what you mean.

You can determine the R-Value if you also take other measurements for the process.

Then, while your camera shows areas that are presumably insulated....it fails to note the fact that the insulation has been smashed into place or otherwise flattened, or fails to be flush with every edge, or is bent to make it fit....which can reduce its R-value by up to 50%. None of that shows up in your picture which makes your picture, at best, misleading.

More "Not".

If there is any change in density of the insulation, it does in fact show up.
And you can determine the differential of the R-Value with the camera.

Second to fenestration, the biggest losses of energy occur from air leaks through the ceiling....and to an air leak, insulation is nothing but an "air filter" for the air as it leaves the building.

Second to fenestration?
Ceiling air leaks are a greater loss in many, if not most energy losses that I find.

#1 HVAC loss (it is always under the high (+/-) pressures during operation).
#2 Upper level air leakage (relative to the pressures of stack effect). Though this is tested a 50 pa, you will never see pressures as close to the HVAC equipment with stack effect.
#3 Lower level leakage (proportuniate with upper air leakages as well as outdoor ambient conditions like wind).
#4 Insulation losses.
#5 Turning up the heat/ac too much.

[kweiss]

Originally Posted by jbushart

The bottom line is this:

A thermal image of a ceiling, by itself, is as good at informing you about the effectiveness of the attic insulation as shining a flashlight on an air return vent will tell you about the effectiveness of the heat pump.

What an incredibly ignorant and ridiculous statement.

I will grant that air loss is important. I will also grant that a 1 x 1 square of missing insulation in a 20 x 20 room is not overly significant and tell my clients that.

However, I find several houses a month with SIGNIFICANT (more than 50% of a wall of ceiling) missing insulation or even room with none at all. Usually in completely inaccessible attics that would require destructive investigation to inspect. These are hugely significant.

Stupid statements like that just make everyone in our field look dumb. Please refrain unless you have something constructive to add.

[James H. Bushart]

Originally Posted by kweiss

What an incredibly ignorant and ridiculous statement.

I will grant that air loss is important. I will also grant that a 1 x 1 square of missing insulation in a 20 x 20 room is not overly significant and tell my clients that.

However, I find several houses a month with SIGNIFICANT (more than 50% of a wall of ceiling) missing insulation or even room with none at all. Usually in completely inaccessible attics that would require destructive investigation to inspect. These are hugely significant.

Stupid statements like that just make everyone in our field look dumb. Please refrain unless you have something constructive to add.

Insulation over an air leak is nothing more than an air filter for the outgoing conditioned air.

An energy audit conducted only with a camera does not measure or find the leaking air. Recommendations to tighten a house...without knowing how it will affect the exhaust of the combustion appliances....is not only amateurish and plain stupid....but deadly.

The public needs to know that there is 80% more to a real energy audit than a thermal image. You are not helping.