Originally Posted By: Steven Brewster This post was automatically imported from our archived forum.
Hey folks,
Inspected this home yesterday and found what I think is moisture intrusion and lack of ventilation on the NW sections of the roof structure. The roof covering is 16 yrs. asphalt dimensional type, pitch >8/12. None of the power roof vents functioned and the small soffit vents louvers were obstructed by paint and improperly installed insulation (obstructed ventilation). Never seen this much staining, it almost looks like thinned roofing tar in some areas. Moisture content in these blacken areas ranged from 8% to 18%. None stained areas had 8% mc. I would appreciate shared thoughts.
Could not access this area in the attic space (no access) but it appears that the lack of ventilation and roof covering failure has damaged the decking.
Originally Posted By: wdecker This post was automatically imported from our archived forum.
Beginning of rot. Older stains (and every attic has some) are usually as dry as the surrounding wood. Usually, active rot does not begin unless you have at least 19% moisture content, but how do you know your meter is accurate?
MAYBE, with proper ventiliation, this can be forstalled, at least untill he needs a new roof. I would have to see some roofer step through that decking.
Recommend evaluation and repair by a licnesed and insured roofing contractor.
Originally Posted By: apolillo This post was automatically imported from our archived forum.
Steven,
Is there a bathroom under the area in your first picture? I have seen that localized staining caused by a bathroom vent that terminates in the attic, not the exterior.
Originally Posted By: Steven Brewster This post was automatically imported from our archived forum.
No bathroom near any of these areas. Pretty much open rafters in all areas. I really thinks that most of this is due to a failing roof covering and lack of ventilation, especially over the carport. Of course, I recommend evaluation by a licensed roofing contractor. Also, recommended ridge venting and evaluation/repair of the improperly installed insulation by a licensed insulation contractor.
Thanks for the input. I never have seen this type finding as prolific as this and only on the NW side of the roof system.
Originally Posted By: Steven Brewster This post was automatically imported from our archived forum.
William,
I use a Protimeter SurveyMaster moisture meter and check the cal. according to the mfg. provided tool at each inspection. How do you check yours for proper calibration and accuracy?
Thanks for the reply. 
Originally Posted By: mcyr This post was automatically imported from our archived forum.
Steven; Is it possible this roof leaked before the new roofing was installed 16 years ago? How old was the dwelling?
It appears that if you were reading 12-19% moisture that it has not leaked in awhile, but definitely has a ventilation problem where the attic is overheating and cause buckling and curling of the roofing as the picture shows.
Would highly recommend a roofing Contractor to evaluate the condition and cause of this problem.
Originally Posted By: Jay Moge This post was automatically imported from our archived forum.
i’m with Marcel.
how about a roof leak 17 years ago, some roof tar “for now” then in the spring or when they got the money, a new roof, but the sheething dried ok. just replace the paper, ice/water, and shingles? that black stuff looks like it came from the other side.
Originally Posted By: Steven Brewster This post was automatically imported from our archived forum.
The roof is probably original since the home was built in 1989. The owner has contacted their insurance comp. to evaluate for wind/hail/water damage. Hopefully, the insurance company will make some or replace the roof covering. I have seen at least two complete roof replacements from insurance companies after I recommended a roofing contract/insurance comp. evaluation. Sometimes this is a good thing for both parties.
Originally Posted By: psisler This post was automatically imported from our archived forum.
Steven,
I noticed in one image the insulation in the attic. Were the soffett vents covered by the insulation? I also noticed that there were no turbine or ridge vents. Was there any other venting in the roof? Some so called contractors will lay a new roof right over the old without laying felt down first. Was there a second layer of shingles? If so was there felt layed down? Shingles alone do not provide adequate protection from moisture intrusion. There is a myraid of items that could be attributed to this situation. I always check the layers if there are more than one for felt. Just my opinion. Hope it helps.