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  #16  
Old 1/21/19, 12:54 PM
David A. Andersen, TN HI# 40's Avatar
David A. Andersen, TN HI# 40 David A. Andersen, TN HI# 40 is offline
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Default Re: Tell Me What You See!

William, I think you made a great assessment with the available information provided, which is insufficient to make a determination of anything one way or the other. I especially like your statement "So, the logical approach would be to employ a process of elimination."! We should spend more time on "what it is not" than "what it seems to be".



ie. there is information about flashing and roof issues that were not addressed because of existing weather conditions. Is there not access to the underside of the roof in these locations?



I see discoloration in the digital pics: however, this does not verify actual roof/flashing leakage.



1. We are looking at scans in a room that frequently experiences 100% rh during use. Any slight heat loss in the building envelope will result in condensation.

2. Cooler Sheetrock promotes condensation of water vapor. So what is causing cooler temps? Well we must consider the three methods of heat transfer; conduction, convection and radiation. As the top of the ceiling or walls are not exposed to the sky, we can "eliminate" radiational cooling. Will a lack of proper insulation allow air movement and subsequent heat loss. Yes it would, but we may not be able to assess this visually without invasive inspection. Does the density of materials use to construct this building envelope cause some areas to conduct heat at different rates?



There are two other considerations. Can we use our IR Building Science training to determine "Apparent R-Value" of the cooler spots of the wall/ceilings? Or we can just assume that there is no insulation there based on the knowledge of construction practices were insulation is not used in particular areas. Second, we can use psychometrics to determine what temperature we should be expecting from wet evaporating objects subject to the ambient air. For example if the thermal exception is colder than the calculated wet bulb temperature, we are not looking at just evaporative cooling. This leads to the possibility that this is not a roof leak. We can not exclude this from being water, but that it could be water due to adverse conditions such as air leakage and/or inadequate insulation.



My next step would be to apply a convective heat source to the anomaly and record the reaction. This is the the only method to detect moisture over air leakage and insulation issues.



3. Thermal assessment: how do the thermal anomalies represent the occurring heat transfer? There are numerous targets in each thermal scan. How do each of these target areas represent the heat transfer? Did you tune your scans for each and every target represented in the scan? If not, the Delta T data will be significantly in error.



Without accessing the raw data in these scans, and reliant on the limited data provided, I can eliminate 99% of the thermal exceptions based on what I know about how buildings are constructed in my area, and how they fail to function as intended. I would conclude that "if" this were a moisture issue (Leakage), it could be a condition where past leakage had occurred but has significantly evaporated over a substantial period of time. My next act would be to cause the leak to occur and document it as it happened.



4. "If" what I see in digital pics is in fact water staining, taking moisture meter readings is insignificant information. Sticking the wall/ceiling with a moisture meter may or may not record moisture. Thermal scans indicate that if this is moisture, it is an inndiract measurement of conditions deep inside the wall (likely beyond the functional ability of a commonly used moisture meter). Either way, the information is irrelevant because the current condition depicted by IR indicates evaporated moisture (if anything). You will not get usable data using a moisture meter in this state.



If you don't go find more data, this inspection is inconclusive as to the "source" of this condition. Even if you can say it's wet, you can not determine the source of why it is wet. Subsequently you can not fix the problem. This leads to the people that call me and tell me they have spent thousands to fix the problem, but it's still there and they have no idea what to do about it.



David A. Andersen & Associates
Clarksville - Nashville Home Inspector Lic#40 (Retired)
ITC Level III Thermographer Cert#1958
Building Science Thermographer Cert#33784
HVAC Certification EPA Cert#2046620
BPI# 5015804
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  #17  
Old 1/21/19, 8:40 PM
Dan Bowers, CMI, ACI's Avatar
Dan Bowers, CMI, ACI Dan Bowers, CMI, ACI is offline
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Default Re: Tell Me What You See!

All points well taken, and my thoughts were inconclusive without further testing or evaluation. Which in some locations is not possible due to weather or areas with no access ............... AND if buyer is not willing to spend more $$$$$ OR seller will not give them more time extension. There it is .............



Dan Bowers, CMI
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  #18  
Old 1/22/19, 7:12 PM
William B. Ogletree's Avatar
William B. Ogletree William B. Ogletree is offline
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Default Re: Tell Me What You See!

Quote:
Originally Posted by dbowers View Post
All points well taken, and my thoughts were inconclusive without further testing or evaluation. Which in some locations is not possible due to weather or areas with no access ............... AND if buyer is not willing to spend more $$$$$ OR seller will not give them more time extension. There it is .............
I think this raises a question we as inspectors need to consider: Is it unprofessional to be reporting on conditions we find if we cannot offer some convincing explanation that might indicate an actual problem?

My inspection today presents a perfect example. Take a look at the two attached IR images.

These photos are from either side of a wall dividing a first floor shower stall from its adjacent bedroom. Obviously something is warming up the ceiling in this area, but what?

It could not be warm water, since the water heaters were not lit at the time the photo was taken. I seriously doubt it was wiring, as the lighting in the house was LED, which draws very little current.

This was new construction, and the kitchen appliances were not installed, thus could not be drawing current.

I had been running the furnace for a while before capturing these images, so I shut off the furnace and went about inspecting the rest of the property. I came back about an hour and a half later and the warm spots were gone. At that point I felt a reasonable guess would be that there was a leaking air duct in the area, but I would have to have removed sheathing in the attic to visualize the area, so I could not confirm it.

In this case, I feel I was able to eliminate enough other possibilities to form a plausible hypothesis (leaking ductwork), so I included it in my report.

A few weeks back, though, I found a warm spot that I could find no plausible explanation for. I did not include mention of it in my report, but did discuss it with the buyer.

What say the rest of you? Do you report an anomaly even if you can't offer a plausible explanation?
Attached Thumbnails
Tell Me What You See!-flir0522-jpg   Tell Me What You See!-flir0523-jpg  




William Bruce Ogletree
Ogletree Inspection Services

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  #19  
Old 1/22/19, 7:31 PM
Chuck Evans's Avatar
Chuck Evans Chuck Evans is online now
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Default Re: Tell Me What You See!

Quote:
Originally Posted by wogletree View Post
I think this raises a question we as inspectors need to consider: Is it unprofessional to be reporting on conditions we find if we cannot offer some convincing explanation that might indicate an actual problem?

My inspection today presents a perfect example. Take a look at the two attached IR images.

These photos are from either side of a wall dividing a first floor shower stall from its adjacent bedroom. Obviously something is warming up the ceiling in this area, but what?

It could not be warm water, since the water heaters were not lit at the time the photo was taken. I seriously doubt it was wiring, as the lighting in the house was LED, which draws very little current.

This was new construction, and the kitchen appliances were not installed, thus could not be drawing current.

I had been running the furnace for a while before capturing these images, so I shut off the furnace and went about inspecting the rest of the property. I came back about an hour and a half later and the warm spots were gone. At that point I felt a reasonable guess would be that there was a leaking air duct in the area, but I would have to have removed sheathing in the attic to visualize the area, so I could not confirm it.

In this case, I feel I was able to eliminate enough other possibilities to form a plausible hypothesis (leaking ductwork), so I included it in my report.

A few weeks back, though, I found a warm spot that I could find no plausible explanation for. I did not include mention of it in my report, but did discuss it with the buyer.

What say the rest of you? Do you report an anomaly even if you can't offer a plausible explanation?
That is where the duct is in contact with the sheetrock on the ceiling. When you run the A/C it will be cold. You will often find that in transitions to/from a ceiling area where there is minimal space between the ceiling and the roof (like at the transition from an attic space over a first-floor area up to the upper attic).

I do not report these unless we have dewpoint issues.

I know that the above did not answer the broader question that you posed to us. My approach is to perform enough deductive analysis, observation and testing in order to develop at least a likely theory as to the source of the anomaly, which depending on the condition may or may not be comment worthy. I figure that's what people are paying me for and I do, in fact, charge a fee for performing infrared thermography at an inspection. I cannot even think of the last time I reported an unknown anomaly, if ever. If I as the thermographer who can see the anomaly can't figure it out, what is a contractor who doesn't have my equipment going to come up with? Reporting phantom anomalies for someone who can't see them to try to investigate would simply create a frustrating exercise for both the buyer and seller. You can't just hand-off undefined thermography exceptions for someone else to figure out.



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Last edited by cevans; 1/23/19 at 10:14 AM..
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  #20  
Old 1/23/19, 1:21 PM
David A. Andersen, TN HI# 40's Avatar
David A. Andersen, TN HI# 40 David A. Andersen, TN HI# 40 is offline
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Default Re: Tell Me What You See!

Quote:
Do you report an anomaly even if you can't offer a plausible explanation?

NO.



All too many camera owners pull out equipment (like a thermal camera) in a Home Inspection, see something and then fall back on "This is a general inspection outside the scope of a Home Inspection". When you pull out more than a flashlight, you have given up the right to fall back on "This is just a Home Inspection".


As you have eliminated several options, what you have left is sufficient cause for an existing problem that warrants mention. You just didn't point out a hot spot.


As Chuck pointed out, the A/C would make the same spot cold. If weather permitting, I switch between Heat and A/C. Personally I can run the A/C at any temperature, but others must be conservative here. This confirms leakage based on how fast, and where things change to cold.



Also he noted "I do not report these unless we have dewpoint issues". Do not forget that we see this in winter as hot. If your in Texas, this will be a dewpoint issue come summer.


Also I note that the hot anomaly extends further away from the hotest spot in several locations. Based upon how long the heat was on, this shows the extent and rate of heat transfer within the building envelope.



Because this is a bathroom where hot water usage is a primary activity, this would elevate my concern about this condition.



We should never just refer this to someone else, except another thermographer because they do not have the ability to replicate what we have done.



Based on the OP, I do not run into the problem of finding something that the client does not have the money to verify the real problem. That in of itself eliminates inclusion in a report. I tell the client that there are particular issues that indicate a problem to me but additional fees will be required to verify. There were roof and flashing concerns, but conditions were not present to complete this inspection at this time. They can just have a roofer to poke around, or I can come back on another inspection and determine the specific repairs needed if there are any.



David A. Andersen & Associates
Clarksville - Nashville Home Inspector Lic#40 (Retired)
ITC Level III Thermographer Cert#1958
Building Science Thermographer Cert#33784
HVAC Certification EPA Cert#2046620
BPI# 5015804
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  #21  
Old 2/14/19, 12:29 PM
Glen Gallo Glen Gallo is online now
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Default Re: Tell Me What You See!

I would agree with Mr Ogletree and others without a moisture meter we are guessing and not that well. I think the imaging is good but more information is needed. My camera is a liar so I have to work to get the truth out

would like picture of outside where photos are

what was the inside outside temperature was delta t reached?

is there solar loading?

time of day outdoor conditions

is there ventilation nearby?

what are the camera specs and settings?

the first image i see possible moisture possible misaligned insulation possible wind washing what I would be most interested in investigating further would be the concentrated cool area to the left on the flat wall

second image looks like missing insulation but we need to test and investigate further

Third image is a throw away for me tile does not image well too shiny and the moved bathmat is problematic. perhaps some electrical tape across it

the fourth image the anomaly looks slight is the can ac it? is it original or remodel? Venting near by on the outside? it looks like misaligned insulation but moisture test and conditions around it need to be vetted before analysis.

new to this site and not yet certified as an inspector but getting there.

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Last edited by ggallo2; 2/14/19 at 12:30 PM.. Reason: proof reading
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