Originally Posted By: rwills This post was automatically imported from our archived forum.
Phil, Thanks for the quick reply and I pray you’re right but then that raises the questions How? Why? etc. If dirt, you would think it could be wiped off but this appears to be in the wood itself. I have seen this reaction in Fire rated sheathing due to the chemical recation to heat in summer but this is not FRT. The owner emailed and asked me if he should get a mold inspection done. I doubt it is and pray it’s not!
Originally Posted By: phinman This post was automatically imported from our archived forum.
The first home I saw it in was a friend of mine’s home. He had with him that day another friend who has been doing mold remediation for 20 years and has all kinds of training and he told me without a doubt what we were looking at was not mold.
He has since done 4 mold clean up jobs that I inspected. Has done very well!
A very small amount came off in my hand when I wiped my hand across the wood, but not much!
The next time I inspected a really old home I took notice that it had a tremendous amount of the substance and I recalled working on these old homes and coming home filthy from the stuff.
Originally Posted By: ekartal This post was automatically imported from our archived forum.
phinman wrote:
I saw this in a home with no apparent reason or causes. House was 45 years old. Ventilation was ok and no bath fans vented into the attic.Phil
Often due to lack of insulation. Wet crawl space by any chance?
Robert, if you had not mentioned it being tested I would for sure said mold. In fact I still think it is. Never seen a dirt build up on the underside before. 
Originally Posted By: rwills This post was automatically imported from our archived forum.
Paul,
No, there is no fireplace and the heating unit is natural gas. The place is 50+ years old and the soffitt venting was blocked of by insulation. Notic from the photos that there is not much darness visible on the rafter framing, just on the sheathing underside. My next guess is whether the owner had insulated the rafters at one time and then removed the insulation possibly trapping moisture between the insulation and sheathing. I’m going back next week to examine it again and take more photos.
Originally Posted By: rwills This post was automatically imported from our archived forum.
Quote:
"Often due to lack of insulation. Wet crawl space by any chance?"
Erol, home is actually on a slab. Why do you think it's mold? There are no moisture conditions in the attic whatsoever that would be conducive to mold. Being 50+ years old, I'm thinking any number of reasons could relate to the condition. For instance, smoke/soot from an old heat system, ghosting, and yes, perhaps old mold condition from an improperly insulated roof. just to name a few! I'm surprised more inspectors haven't chimed in and are aware of, or ever seen this! Must be pretty rare whatever it is!
Originally Posted By: aslimack This post was automatically imported from our archived forum.
Sure looks to me like inadequate ventilation. If the soffit venting is blocked as you say, no question thats where i’d be looking. No inlet air is certainly going to limit the ventilation. This is what will happen. Also, if that insulation doesn’t have a vapor barrier, that could also contribute. Look to see if the discoloration is darker over the bathroom or kitchen. This may also give you a clue.
Though the color doesn't look extensive, i'd advise taking a screwdriver up with you and poke around just to be sure the rafters and deck aren't rotted/rotting. I've seen whole 10 year old roofs that had to be torn off and the structure and deck replaced due to blocked soffit vents. Sometimes this will be reflected by excessive dips in the roof, notable from the outside. Many roofers and siders have a very limited understanding of the dynamics of ventilation.
Side note: If it were me and the deck and structure are sound as they appear, i'd be using an old broomstick with a notch cut out to hold a baffle snuggly in it. I'd go around the attic with a stack of baffles cut in half to 2 ft. lengths. I'd stick the baffles into the soffits and give the broomstick a little twist if needed, to release the baffle from the stick. Saves the back and knees, and maybe the ceiling below.
Originally Posted By: aslimack This post was automatically imported from our archived forum.
Robert,
When i see this condition, i recommend increasing the inlet air,(Soffit) A.S.A.P. I explain to the client that if the soffits are blocked, its more or less like tring to blow into a glass. Without air being able to enter and exit somewhat equally, you are going to have a dead space and limited if any actual venting. If the only result to date is the discoloration, the ventilation baffles along with proper outlet venting should do the trick.
I'm assuming the outlets vents and the soffits are adequate other than the soffits being blocked.
Originally Posted By: aslimack This post was automatically imported from our archived forum.
Yeah Paul,
I used to insulate new homes for about 6-7 years. When things would get slow, i'd help the retrofit crew. (Blown-in) I'd spend half my day on stilts with a hammer stapler in one hand and a razor knife in the other. I also wore a mask, but that was only to hide my true identity. With that experience, any friend that needed to upgrade their insulation over the years would call me. I never used the "broomstick trick" professionally. That was one i developed on my own while helping friends.
Originally Posted By: phinsperger This post was automatically imported from our archived forum.
So no moisture problems… Age of the roof and the condition of the tips of the nail? rusted? clean?
The condition does not appear on any structural members. Just the sheathing right?
A post construction chemical treatment maybe.
Aerials I see in attics are more often than in row houses. Was this a row/town house? If so a chemical fire retardant treatment may have been added afterward as opposed to using FRT sheathing.
I just taking stabs in the dark. I don't really know
Originally Posted By: rwills This post was automatically imported from our archived forum.
Yes, I already indicated to the owner that the soffitt vents had been blocked by insulation and the cause was more than likely related to this. Now they appear to be more concerned about the fact that the dark stuff is mold and if it is toxic!
Originally Posted By: phinman This post was automatically imported from our archived forum.
Some more info on the home I inspected.
There was dirt around the gable louvers as if the dirt was entering from the outside from an attic fan! Low and behold though no attic fan. I have since noted the same issue on other homes but I do not have an answer for that.
The same substance was also in the garage! No ventilation problems present there.
Home had a dry basement, gas heat and 3 1/2" of insulation. There did not appear to be any soffit vents. There were no ridge vents either.
Like I said, the same substance I have since noted in EVERY 50+ year old home. The older the more was present.
Bob, See if Joe can help you out like he did for me!
Originally Posted By: aslimack This post was automatically imported from our archived forum.
Remember that a 50’s home, when built, was alot less airtight than it would probably be now. Less insulated as well. As fuel cost have risen, more efficient windows and additional insulation have likely been added. All this has an affect on the dynamics of the home. Where lesser venting may have worked in the past, the fact that the house is tighter due to these improvements will create an entirely different situation within the home. The added efficiency will also affect the likelyhood of things like bathroom/showers affecting the home in this way. The tighter the house becomes, the less areas for moisture to escape. Venting often needs to be improved as the home is made tighter.
Originally Posted By: dhartke This post was automatically imported from our archived forum.
Bob said
Doesn’t appear to be mold either, this was verified by an environmentalist. Thanks
Was a mold test actually done? If not it should be. I'm not a mold guy but it sure looks like mold and with no good ventilation the stale air may contain enough moisture. With the current scare of mold you must protect your client and yourself.
I doubt it is and pray it’s not!