Black stripes on sheetrock at each stud

[jdamato (Jason B. Damato)]

Hi all,
I Was emailed a pic of Sheetrock in a bedroom that had black stripes at each tape seam on the walls and ceiling. What do you think it is ?

[jjonas (Jeffrey Jonas)]

@Title

**Black stripes on sheetrock at each stud

**

@jdamato

Hi all,
I Was emailed a pic of Sheetrock in a bedroom that had black stripes at each tape seam on the walls and ceiling. What do you think it is ?

At “each stud” or at “each tape seam”??? Makes a difference.

Most likely “ghosting”.

[jdamato (Jason B. Damato)]

Sorry, each stud.

[jshishilla (John Shishilla)]

Like this? Soot, from candles.

[jdamato (Jason B. Damato)]

Yes like that. I can’t post pics from my iPhone. I just thought it was odd being at each stud.

[tpappas (Troy N. Pappas)]

Thermal Bridging

[mroberson (Michael Roberson)]

I think Troy has the literal definition. “ghosting” is the common name.

Are there/were there candles in this bathroom? Perhaps a wood fueled heater nearby? Heavy smokers?

[rcooke (Roy D. Cooke, Sr)]

http://www.nachi.org/forum/f18/dark-spots-nail-heads-and-studs-1294/

http://www.nachi.org/forum/f18/would-cause-drywall-do-43554/

http://forums.finehomebuilding.com/breaktime/energy-heating-insulation/ghosting-studs-showing-walls

[joverholser (John Overholser, MD: 31233, WV: HI4572294-0717, VA:3380000836)]

Yep, I agree with Troy – thermal bridging causing condensation to trap dust.