What teh heck is this?

[Marc M]

So I saw this discoloration today. I scanned the area and there was an obvious significant difference in surface temp both spot Radiometer and IR as show here in pics.
After testing via moisture meter, it was determined that the area was dry with no elevated moisture content whatsoever.
What I don’t get is..., if there is missing insulation behind there okay I get that, but where did the stain come from? Creepy...:eek:

[H.G. Watson, Sr.]

A bad paint (or lack thereof) paint job.

The amature painters missed a spot while they were rolling the ceiling. Doesn't appear to be a stain in the photos you posted but an area what was not coated. Some of todays paints have some significant reflection and insulation properties, esp. those all-in-one coat ceramic enhanced ones.

Are the 80s style full-height euro-cabinets original to the home? perhaps the original were shorter height installed under a sofit, since removed, and the area is lacking insulation at the ceiling transition or unblocked joist cavity and the missed re-painted area highlights this more significantly.

Is there an exaust duct for a hood or microhood present (was there once one in the area and improperly abandoned or its decomissioning incomplete, re restoring insulation and remediating air/vapor retarder at its former termination) or bi-pass above.

Is there a floor register, air handling duct or trunk immediately above?

The inside wall opening increased to expand or open the kitchen or closet knocked out?

[Marc M]

The amature painters missed a spot while they were rolling the ceiling. Doesn't appear to be a stain in the photos you posted but an area what was not coated. Some of todays paints have some significant reflection and insulation properties, esp. those all-in-one coat ceramic enhanced ones.Are the 80s style full-height euro-cabinets original to the home? perhaps the original were shorter height installed under a sofit, since removed, and the area is lacking insulation at the ceiling transition or unblocked joist cavity and the missed re-painted area highlights this more significantly. Is there an exaust duct for a hood or microhood present (was there once one in the area and improperly abandoned or its decomissioning incomplete, re restoring insulation and remediating air/vapor retarder at its former termination) or bi-pass above inside wall or closet knocked out?
That was what i was thinking also. Most especially with the IR test.

[Jim Luttrall]

Removed fir down (soffit, bulkhead) above old cabinets. Missing insulation above. I'm guessing you could not get to the attic above.
The stain could be a bad patch and paint job but also could be due to temperature difference and fumes plating out on ceiling due to the temperature difference.

[Vern Heiler]

I believe you can see where the painter used a shield along the straight wall that extended into the room (sharp line) with over spray at the other edges of the holiday (missed spot). Painter meant to come back and paint the inside corners but forgot.

[Ken Rowe]

If that was in MN I'd say it was a past condensation stain due to the missing attic insulation.

[John Kogel]

I had similar patterns which was soot from scented candles, missing insulation. I'll try to dig up the pics.

[Rolland Pruner]

Possible heat duct area??

[Garry Blankenship]

Pretty good sleuthing there boss. The IR photo complete with a temp gauge is very cool. Based on that distinct temp outline, I'd say it's not the paint. Radiant heat in the ceiling and that area once had cabinetry or ? now removed ? Or - - - there is a fixture, roof vent or similar above creating that temp. foot-print ? Are you willing to share what IR equipment you are using ?

[Benjamin Thompson]

What Jim said. I think it's referred to as "ghosting" (technical term, no doubt). Often you can clearly see the outlines of the ceiling joists.

[Mike Kleisch]

I agree with Ken, if it was in WI I would say the same. I've seen stains like this where the moisture was high in the home and water condensed on the surface during cold nights where insulation was missing. After it dried the area was stained a different color from the rest of the area.

[Marc M]

I ran through all these possibilities. The only thing is that is was "everwhere" in the house. i mean all over. Spots on walls, ceilings...just weird. And in all places, the temps was different. Even on ceilings that were insulated (above).
Garry, These images were taken with my FLUKE TI 32.

[Garry Blankenship]

I ran through all these possibilities. The only thing is that is was "everwhere" in the house. i mean all over. Spots on walls, ceilings...just weird. And in all places, the temps was different. Even on ceilings that were insulated (above).
Garry, These images were taken with my FLUKE TI 32.

Based on your "everywhere" post above, I don't know if it's a recommendation or a condemnation of your FLUKE.

[John Kogel]

This house I did in the spring had similar staining. Black squares, black marks around pot lights, black dots on a bedroom ceiling that lined up with soffit vents. I noticed candles all around the place. In the attic I saw missing insulation. I believe cool patches on the ceiling become damp with condensation, causing soot to collect there.

[Marc M]

This house I did in the spring had similar staining. Black squares, black marks around pot lights, black dots on a bedroom ceiling that lined up with soffit vents. I noticed candles all around the place. In the attic I saw missing insulation. I believe cool patches on the ceiling become damp with condensation, causing soot to collect there.

Well played John, sounds good to me.

[Vern Heiler]

I ran through all these possibilities. The only thing is that is was "everwhere" in the house. i mean all over. Spots on walls, ceilings...just weird. And in all places, the temps was different. Even on ceilings that were insulated (above).
Garry, These images were taken with my FLUKE TI 32.

Mark, were you able to inspect the attic area above the pictured space in the op pic?

[Marc M]

Mark, were you able to inspect the attic area above the pictured space in the op pic?
no, that area wasnt accessible.

[Alan Ditsworth]

Thermal tracking? Air/moisture loss through ceiling due to the lack of insulation in that area.

[Jimmy Cope]

Is there a wood stove or wood fireplace in the house? Cooking can also cause this. This is what I call the "tepee effect". Contaminates are pulled through and filtered by the drywall where the insulation is missing. Note the narrow clean strip between the two squares. The contaminates cannot pass through the 2 x 4 ceiling joist. If there is an attic fan it can cause a negative pressure area in attic. This is my take on the observation..

[Stuart Brooks]

Ghosting a.k.a. Thermal Tracking
Dark Ceiling Stains: How to Recognize & Diagnose Thermal Tracking, Ghosting, Thermal Bridging, Dark or Sooty Stains on Building Ceilings [or walls] (http://inspectapedia.com/interiors/ThermalTracking3.htm)

[Raymond Wand]

Ghosting - Michaels Engineering
https://docs.google.com/viewer?a=v&q=cache:th2JxJNsz3oJ:www.michaelsengineering.com/Briefs/Briefs%2520PDFs/IAQ/Ghosting.pdf+Brownian+motion+ghosting&hl=en&gl=ca&pid=bl&srcid=ADGEEShogJ5fDsVeqFYEMGXdOhyksis_4eVAJYHAK07g omC0MnTuUiiQiRaZU5XBOW2R3fzWYCHeSluemu-poyM3TAqJAT2BCDRfvnHRpbWrDazkVi42iHj-A6WiHCeHjYmo4tBdXvNj&sig=AHIEtbSnUmFp7L-Hk-C7QnU4uOH376YJCQ

Brownian Motion
The problems are related to four deposition mechanisms: filtration, electrostatic attraction, thermal deposition due to Brownian motion and impaction. These deposition mechanisms cause tiny microscopic airborne particles to:
• "filter out" in carpets;
• "plate out" on charged surfaces due to electrostatic attraction
• "plate out" on cold surfaces due to "Brownian motion"; or
• "plate out" on surfaces due to impaction.

[Garry Blankenship]

Ghosting - Michaels Engineering
https://docs.google.com/viewer?a=v&q=cache:th2JxJNsz3oJ:www.michaelsengineering.com/Briefs/Briefs%2520PDFs/IAQ/Ghosting.pdf+Brownian+motion+ghosting&hl=en&gl=ca&pid=bl&srcid=ADGEEShogJ5fDsVeqFYEMGXdOhyksis_4eVAJYHAK07g omC0MnTuUiiQiRaZU5XBOW2R3fzWYCHeSluemu-poyM3TAqJAT2BCDRfvnHRpbWrDazkVi42iHj-A6WiHCeHjYmo4tBdXvNj&sig=AHIEtbSnUmFp7L-Hk-C7QnU4uOH376YJCQ

Brownian Motion
The problems are related to four deposition mechanisms: filtration, electrostatic attraction, thermal deposition due to Brownian motion and impaction. These deposition mechanisms cause tiny microscopic airborne particles to:
• "filter out" in carpets;
• "plate out" on charged surfaces due to electrostatic attraction
• "plate out" on cold surfaces due to "Brownian motion"; or
• "plate out" on surfaces due to impaction.

Great informantion - - - THANKS