Anyone explain this???

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Anyone explain this???

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ROGER CHEWNING

CHEWNING INSPECTION SERVICES, INC
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Posted: Nov 22, 2005 7:40 PM       Post Subject:
First time I've ever seen this.... Realtor said she had seen it before and never had it explained... This is the dining area, with the kitchen to the left, and I'm standing in the living room.... the living room has similar "markings," but the dining area photographed better... I'm puzzled! What would attach itself to the wall covering ONLY over the wood support members???? It looks like an x-ray!! I tried to wipe a spot off, but no luck... Can anyone help???
[ Image: wall x-ray ]
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Larry Kage

Welcome Home Inspection Services, LLC
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Posted: Nov 22, 2005 7:48 PM       Post Subject:
I seem to recall it being called "ghosting" from burning scented candles, plug-in air fresheners and the like.
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ROGER CHEWNING

CHEWNING INSPECTION SERVICES, INC
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Posted: Nov 22, 2005 8:03 PM       Post Subject:
Thanks LKage, that would tell me what caused the shadows, but I'm still wondering why only on those areas.. I'll research "ghosting"......I was thinking that since it was a common wall /ceiling with the kitchen, it was from cooking... That, however, isn't as "defined" as this image (just ask my wife!!).... nachi_sarcasm.gif I love you, Honey!!
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rmoore
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Posted: Nov 22, 2005 8:10 PM       Post Subject:

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I've only seen it once before and nothing as well defined as Roger's. In my case it was only on the exterior walls near the ceiling. Never did really find out what it was, but I suspected that the eave vents in those areas were making the framing colder and causing localized condensation, which in turn contaminents/dust in the home was adhereing to. In fact, I could measure about a 5-10 degree drop in temperature at the ghosting.

In Tampa...who knows...but I would guess it has something to do with heat/cold transfer at the framing.

Roger, got any more info on the wall locations and exterior cladding, etc?
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Michael Thomas

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Posted: Nov 22, 2005 8:19 PM       Post Subject:
Ghosting: look around 1/2 way down this page on the right hand side, or just search for "ghosting":

http://www.atlantic-environmental.com/articles.htm

This site also has some useful information, but was down when I checked it:

http://hem.dis.anl.gov/eehem/98/980109.html#98010905
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Erby Crofutt

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Posted: Nov 22, 2005 8:43 PM       Post Subject:
The technical name for it is "thermal bridging".

The low temperature outside bridges through the structural framing members causing condensation to occur on the inside wall. Dust, smoke, candle soot, etc is attracted to the condensation. The moisture draws the stain into the wall surface making it difficult to wipe off. Usually found only on outside walls.

The result is the staining or ghosting you see in this picture.

If a house has this problem and you have a temperature gun you can measure the temperature differential between the wall over the studs and the insulated portion of the wall.

I'm sure there is a lot more scientific explanations, but that's my nutshell.
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Doug Edwards

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Posted: Nov 23, 2005 11:11 AM       Post Subject:
I think Erby gets the cigar. I bet if you measured those vertical lines you would get a 16" O.C. spacing. Great picture of the problem by the way. You can clearly see the areas where the wall studs fall and the double top plate.

I edited this post. I had intended on saying it was a "great" picture you took, not "get" picture.
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rmoore
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Posted: Nov 23, 2005 4:04 PM       Post Subject:

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Here's a couple more good links...

http://www.cwc.ca/publications/tech_bulletins/bulletin_3/ghost.php


http://www.buildingscience.com/resources/misc/black_stains_on_carpet.htm

--
Richard Moore
Rest Assured Inspection Services
Seattle, WA
www.rainspect.com

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Marcel Cyr

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Posted: Nov 23, 2005 5:52 PM       Post Subject:
icon_smile.gif icon_smile.gif icon_smile.gif

I respect Erby's and Richards post providing all this usefull information, and would add that I have noticed over the years as a Builder, that since screws have taken over the Construction Industry for installation of these products, it appears to have developed this occurrence.

I have seen where drywall has been installed and the screws have become magnetic for some odd reason and attract any metalic particles to it's properties.

Would it be possible in this matter the the solution would pertain to the magnetic resolution of attracting the molecules of the surrounding areas and creating this ghosting affect? Possibillity of the cause, maybe due to the electric drill creating a magnetic field that promotes itself to the screw tip driver. !!

Just a thought, and some might think I am on the second six pack, but I am not.

This is a subject I believe has more than meets the eye.

Is there any people out there with a sceintific background the could add some light to this subject? I think that all non-members and members would appreciate the education.

Thanks.

Marcel
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Roy Cooke

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Posted: Nov 23, 2005 6:35 PM       Post Subject:
mcyr wrote:
icon_smile.gif icon_smile.gif icon_smile.gif

I respect Erby's and Richards post providing all this usefull information, and would add that I have noticed over the years as a Builder, that since screws have taken over the Construction Industry for installation of these products, it appears to have developed this occurrence.

I have seen where drywall has been installed and the screws have become magnetic for some odd reason and attract any metalic particles to it's properties.

Would it be possible in this matter the the solution would pertain to the magnetic resolution of attracting the molecules of the surrounding areas and creating this ghosting affect? Possibillity of the cause, maybe due to the electric drill creating a magnetic field that promotes itself to the screw tip driver. !!

Just a thought, and some might think I am on the second six pack, but I am not.

This is a subject I believe has more than meets the eye.

Is there any people out there with a sceintific background the could add some light to this subject? I think that all non-members and members would appreciate the education.

Thanks.

Marcel

Yes I have seen it and I have to believe it is from the colder wall sections .
Go to Google put in wall Ghosting and WOW! .
Many sites and most say the same thing Here is one .
http://www.clarkpublicutilities.com/Residential/TheEnergyAdviser/Archives2003/03_05_25

Roy sr
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Larry Willick

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Posted: Nov 24, 2005 8:54 PM       Post Subject:
Roger:
This is quite common where there are items in the home such as candles being burned constantly. In our area of British Columbia where we have a lot of families with Shrines in their homes this pattern is prevalent. It is also visible at times on the ceilings. The pattern quite often follows the wall frame and some times the rafter framing. Pattern is linear. Warm and cool areas as defined by insulation and again lack of insulation where wall board is nailed to support framing. For some reason the smoke is attracted to the areas where the frame is. Hope this helps.
Regards,
larry
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Jay Moge
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Posted: Nov 24, 2005 11:02 PM       Post Subject:

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well just to confirm it for the masses. it is "ghosting" and it is caused by less insulated wall section, which condensate and moisture attracts dust and smoke particals which is also elevated by candles and smokers. i see it on ceilings alot and it's easily fixed with a coat or 2 of "killz" or "zinzer 1 2 3" stain primers. oh and of course insulate the sections to eliminate return. icon_cool.gif icon_wink.gif
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James Troth

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Posted: Nov 25, 2005 11:30 AM       Post Subject:
Has anyone ever seen it on the exterior of a home? If so what is the cause of that?
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Marcel Cyr

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Posted: Nov 25, 2005 6:04 PM       Post Subject:
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Thanks Roy for that information.

James, I have seen this on the exterior early in the morning going to work where some asphalt roofs are showing all the lines of the roof framing and in some locations, I have noticed the shadow of the wall framing also.
I can't really explain it,but I am sure someone has seen this too.

It must have to do with the temperature differentials when temperature and humidity levels are at their optimum levels.

Marcel
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Erby Crofutt

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Posted: Nov 25, 2005 9:09 PM       Post Subject:
Thermal bridging is seen on roofs on frosty mornings. Walls on cool wet mornings if the insulation isn't done right.

Melting frost / snow on the roof can help identify poorly insulated areas of the attic.

Done right, it can also help determine if bath fans are vented properly. Ever see a small melted area over the bathroom but nowhere else?
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ROGER CHEWNING

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Posted: Nov 30, 2005 11:33 PM       Post Subject:
Thanks, everyone... I've been without internet for over a week and appreciate all the info. As I found out also, you get a good amount of info when google-ing "ghosting walls". I do not own a "temperature gun" and I don't think my client would appreciate me stabbing my thermostat into the two portions of the wall to find the temp. difference.. HA! I can understand the concept behind the temperature difference and the products of combustion combining.... Thanks again!
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