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Building envelope and Thermal IR Images


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I recently performed an IAQ inspection of a house with a site the sloped upward away from the structure thus promoting flow of rain water toward the structure. I used thermal infrared imaging to view in the interior side of the exterior wall. Several thermal anomalies were discovered along this wall is a wide range of locations. However, none of the areas with anomalies showed elevated moisture when tested with a Protimeter MMS moisture measurement meter in either destructive or non-destructive modes.

Can anyone suggest what conditions in the structure may have lead to the observed anomalies? The house is about 50 years old but very well renovated. Could this be due to cold air infiltration? The anomalies are not regular in shape or distribution.

The photos and brief description can be found at: http://www.iaqforum.net/showthread.php?p=227#post227

Thanks.

Jeff Deuitch

Palmetto, FL

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Originally posted by iaqforum

I recently performed an IAQ inspection of a house with a site the sloped upward away from the structure thus promoting flow of rain water toward the structure. I used thermal infrared imaging to view in the interior side of the exterior wall. Several thermal anomalies were discovered along this wall is a wide range of locations. However, none of the areas with anomalies showed elevated moisture when tested with a Protimeter MMS moisture measurement meter in either destructive or non-destructive modes.

And that's why I dread the onslaught of IR cameras in the home inspection profession.

Can anyone suggest what conditions in the structure may have lead to the observed anomalies? The house is about 50 years old but very well renovated. Could this be due to cold air infiltration? The anomalies are not regular in shape or distribution.

Well, the dark areas are cold. It seems to me that the cold spots have to be from one of three things: water, cold air or a shadow that prevents those areas from getting warm. If you've ruled out water, the next most likely thing is cold air -- I'd look for missing or spotty insulation. But what the hell do I know? I'm not a thermographer.

It's interesting how the black & white picture clearly shows the studs but the color pictures don't. Why is that?

- Jim Katen, Oregon

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Hi Jeff, Welcome to TIJ.

It looks like air infiltration along the sole plate, air infiltration around the window casing and thermal bridging at the studs. I don't know squat about thermography but any of that would be common in any wood framed home from the 50's, remodeled or not.

ONE TEAM - ONE FIGHT!!!

Mike

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Like the other respondents, I'm not a thermographer, but I've taken classes. There's nothing there that looks like water to me; it looks like standard 50's framing w/air leaks.

And yes, I too dread the onslaught of IR in the HI inspection business; it's not something that can be plugged into the sort of scheduling & time frames we have doing "standard" home inspections.

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I noticed that the temp range was only about 12 degrees. The anomalies are more than likely differences in insulation thickness, since you did the right thing and verified with a moisture meter. I see the same thing frequently. Lots of old houses do not have any wall insulation or very little at best. It will also depend on the exterior temp, sun position, wind direction. Insulation, framing, and building material can also influence your image. Be aware.

Kurt, did you buy a camera yet? Prices are coming down!!

(edit) Jim, the studs are also shown in the color - just harder to see. That is one reason why I always use the black & white (greyscale) mode. It's not as dramatic, but, it seems that it has more definition and I'm used to it now. I suspect that the more expensive cameras have a better color palette. Actually, I know they do - I played with one at a school.

(edit 2) Mike mentioned thermal bridging - that is why the studs are defined.

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Originally posted by Jim Katen

Originally posted by iaqforum

I recently performed an IAQ inspection of a house with a site the sloped upward away from the structure thus promoting flow of rain water toward the structure. I used thermal infrared imaging to view in the interior side of the exterior wall. Several thermal anomalies were discovered along this wall is a wide range of locations. However, none of the areas with anomalies showed elevated moisture when tested with a Protimeter MMS moisture measurement meter in either destructive or non-destructive modes.

And that's why I dread the onslaught of IR cameras in the home inspection profession.

Can anyone suggest what conditions in the structure may have lead to the observed anomalies? The house is about 50 years old but very well renovated. Could this be due to cold air infiltration? The anomalies are not regular in shape or distribution.

Well, the dark areas are cold. It seems to me that the cold spots have to be from one of three things: water, cold air or a shadow that prevents those areas from getting warm. If you've ruled out water, the next most likely thing is cold air -- I'd look for missing or spotty insulation. But what the hell do I know? I'm not a thermographer.

It's interesting how the black & white picture clearly shows the studs but the color pictures don't. Why is that?

- Jim Katen, Oregon

Black and white shows more detail. Color shows more contrast. I use both. The camera I use( a FLIR B-2) has numerous color palettes which have different strengths and weaknesses. The effect you refer to probably has more to due with the subject being photographed. Also, when lower temperature range is selected, greater contrast will be seen in either B&W or color.

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Originally posted by hausdok

Hi Jeff, Welcome to TIJ.

It looks like air infiltration along the sole plate, air infiltration around the window casing and thermal bridging at the studs. I don't know squat about thermography but any of that would be common in any wood framed home from the 50's, remodeled or not.

ONE TEAM - ONE FIGHT!!!

Mike

Thanks for the warm reception. The house is actually most CB with frame utilized on the bay shaped area. The B&W image is a window in the CB area. My main concern is that if air infiltration is occurring, then in the summer months with very high water vapor levels could this be a significant condensation risk? If you saw the visible images in second post, then you see how there is cracking and deformity in the small trim piece in the baseboard trim. In February, water vapor levels in SW Florida are not that high and dew point levels are quite low. While not quite visible in the more distant photos, the deformity and cracking was quite evident in many locations along the baseboard.

Thanks.

Jeff Deuitch

Microbiologist

Administrator, The IAQ Forum

www.iaqforum.net

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Originally posted by kurt

Like the other respondents, I'm not a thermographer, but I've taken classes. There's nothing there that looks like water to me; it looks like standard 50's framing w/air leaks.

And yes, I too dread the onslaught of IR in the HI inspection business; it's not something that can be plugged into the sort of scheduling & time frames we have doing "standard" home inspections.

Dread for the prices of these devices for sure. However, their function is thing of beauty once their limitations are understood. I once had a IAQ inspection in an immaculate condo unit. I observed a small (dime sized) round thermal anomoly on the ceiling. IR reflections were ruled out by viewing from many different angles. No staining of any kind was visible to the eye. Upon accessing the attic and focusing on the area where the anomoly occurred, it was discovered that water was dripping off of the A/C refrigerant line and was just starting to make it through the insulation onto the ceiling drywall. If not for IR, this would have gone unnoticed completely. I am not a HI but an environmental scientist. Nor was I even paid to do a detailed inspection, only a visible mold inspection and air sampling. However, IR resulted in helping the client avert a very significant problem that was just beginnning. Since this was an unoccupied unit, it may have been weeks or months before someone would discover a very big problem and an angry phone call to me. While I used to sell IR as a separate service, it is now part of every inspection. Not a luxury, but insurance against hazards to me of the legal variety.

AS for routine HI, time will tell if this becomes standard. If the competition has it, others may lose business as a result. Hopefully prices will come down to real world levels by then.

I hope to get representatives from thermal IR manufacturers to interview on our upcomming Internet TV show "IAQ Television" our first episode should be done in a week to ten days. Check back to The IAQ Forum for updates if you are interested.

Regards.

Jeff Deuitch

Microbiologist

Administrator, The IAQ Forum

www.iaqforum.net

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I used IR cameras as part of developing security infrared detectors. Their use was more educational then anything. Sure, we initially saw stuff that we were not aware of in the white light spectrum but after we learned a few things we didn't employ them so much.

I keep thinking the same will be true here. Once you play with one for a while I believe that most of the stuff that it might find now could be found by visual means and using our heads and establishing improved inspection protocols.

There is no doubt that it is capable of finding things of importance that we might be unable to truly discover visually but I think it will be more of an aid and will indicate a lot of anomalies not within the scope of a normal home inspection.

I just about bought one before this slow winter but put it off indefinitely for now since I had to spend all the money I had saved to survive December.

Chris, Oregon

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I'm not disputing, Jeff; I hear what you're saying. But......

I've come within millimeters of buying one about 6 times so far; it's not the price that's holding me back. If I thought it was that wonderful for this thing that we do, I'd have had one for a year or two.

I guess I'm a little amused @ the implications of what a single drip of water off a condensate line can do. Yes, yes, I know, something could happen, etc., etc., but.......

It's an indication of just how far removed folks are from their habitations. Someone's home is no longer something to be understood; it's something to be mystified by, w/high paid specialists using magic tools to reveal the vast mysteries of the tiny spot on the ceiling.

Only a generation ago, plain folks knew enough to deal w/them.

"Honey, there's a spot on the ceiling"......"Yeah, I know, I looked in the attic yesterday; it's the AC line dripping a little water. I wrapped it in extra insulation and the drip stopped"......

Now we have to have a specialist w/a $12,000 camera to tell us about a drip of water, and have to call in a licensed competent HVAC professional to further analyze the condition and provide specifications for repair & the approx. cost.

It's testament to how far we've slid back down the evolutionary ladder. For someone that's spent their entire life working on homes, I continue to be amazed at how many folks in the HI biz have absolutely no concept of what it means to work on a house.

In that fantasy college we're talking about in the other thread, the curriculum in my fantasy would be anyone entering this business had to spend a couple months doing general labor on construction sites to get some instinctual understandings of how all these houses fit together & work. There'd be fewer magic tools and a lot more thoughtful analysis.

Then, of course, we run into the new breed of engineered materials; my thoughts on that in next weeks column.......

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Comments are right on the mark. Agree as well with education, etc. from other thread.

I did a warranty inspection this past Sunday and I just validated my general home inspection approach to treat them all as an "education".

First of all I learn from each and every one ... then I strive to share that education with my client.

My client was a well educated and successful doctor ... yet maintaining and operating his new 6000+ s.f. custom home was not within his current scope. (ahh.. no pun intended).

He was very interested and a tad excited about learning all that I was explaining when it came to his home's operation. He kept asking if the builder should have shown these things to him when they purchased ... well, yes ... they "should have".

Regardless it just hammers home to me the focus I have to learn all I can, personally and from each inspection and to share that knowledge with my clients.

As for helping one another (yes, even 'newbies') I will do all I can to help and share and continue to learn in the process. After 15+ years in commercial inspections/construction and a mere 5 years in residential I still have a long way to go to become a 'seasoned professional'.

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Looking forward to Kurt's next column. Until then, my 2c...

I'm sure there are HI's who use these cameras as tools to improve their inspections. There is at least one HI in Utah who swears by these things. That HI is very smart, very respected and very honest.

Then, there are the HI's without the knowledge required to perform a basic quality inspection. They are the snake oil vendors of our business who stick out their chests and proclaim the magic of things unseen by the naked eye.

Too bad that wealthy HI's are often the RE whores, but it's fact. They can afford expensive toys. Nobody should be allowed an expensive toy without first proving they have prerequisite knowledge and honest character.

I'm impressed with some of what I see from knowledgeable HI's using these things, but for me, the jury is still out. I'm impressed with some of the baldness 'cures' I see on TV, but as long as Ron Howard wears a baseball cap, I am leery.

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Originally posted by ozofprevI'm impressed with some of what I see from knowledgeable HI's using these things, but for me, the jury is still out. I'm impressed with some of the baldness 'cures' I see on TV, but as long as Ron Howard wears a baseball cap, I am leery.

Hah! Exactly. Then there's Bruce Willis and Jack Nicholson! Exactly the same reason I haven't tried any of them.

We now return you to your regular thread in progress.

OT - OF!!!

M.

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