Do I have a ventilation or roofing issue? Or both?

I live in Indiana and had additional insulation installed in Dec 2014 and a new roof with architectural shingles installed in Aug 2015. At the time of the roof install we changed to a ridge vent. Approximately a month after we spotted mold on an INTERIOR ceiling over a valued ceiling. There is also rust on the ceiling fan down rod and condensation out of the return air duct. At the corner of the ceiling beam I can see spray foam so there was obviously an opening of some kind there previously whether it was a good or bad thing.

I really thought the room mold was caused by blocking some sort of airflow in the room however have recently discovered that there is exposed nail strips where the roofer didn’t put enough rows up to the ridge vent. And they are not covered with silicone or any other sealant. The mold is on one side of the vaulted ceiling where the exposed nails are located and is not accessible.

Compounding the situation the roofer only cut one side of the ridge vent stating that it doesn’t matter if you cut one side double the width or split 50/50. From watching GAF videos and researching I have never heard anyone say to just cut one side. My guess is that if only cut on one side it will not properly draw the air from the soffit vents on the uncut side.

We have also been having issues with mysterious ceiling stains on the vaulted ceilings prior the new roof and was told it was from the roof leaking. A new roof due to hail damage SHOULD fix if that was the case but it hasn’t stopped… From what I have researched I believe this is due to improper ventilation/insulation in these areas. Our home was built in 1992 and we have already replaced all soffit vents with plans to add more. There is also a gable vent on one end…not sure if this is necessary. One person suggested to fix vaulted airflow by installing solar fans over vaulted areas.

So my question here is if exposed nails on a nail strip is the cause of the interior mold or is it improper air flow? Or both? The roofing job was sub contracted by the insulation company.

I have had three different roofers and it seems I can’t find anyone who can nail down the exact cause or that knows enough about ventilation AND roofing!

The Insulation company wants to rip off the roof peak to add spray insulation in the space to the tune of $2700!! My take is that the mold is a result of either the foam insulation or roofer improper install and that we should not be paying for any of it. And that the first step should be removing ceiling drywall (which is in my daughter’s bedroom) as moldy drywall needs to go. From there they can then see how much damage is has been done. And if they refuse to do for comp then what is my recourse? I know the insulation company is bonded-do we pay and go after their insurance?

Sorry for the long winded post-just trying to get all the facts out there so proper advice can be given. I have pictures if I can figure out how to post them.

Thanks in advance.

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It sounds like you have a combination of issues.

The “exposed” nails strips have absolutely nothing to do with it.

Vaulted ceilings are notorious for not having good airflow and not venting properly, cutting a slot on only 1 side certainly isn’t helping but probably isn’t the lone culprit.
There is a very good chance that the insulation is blocking airflow from eave to ridge.

I assume you had some issues prior to the new insulation and roof, now it is just worse?

How long is the run on your vaulted ceiling from eave to peak?
I assume your rafters are 2"x12" or larger.

Unfortunately there are no easy inexpensive fixes for this, there is topside insulation schemes, cold roofs, spray in foam between existing rafters, some combination thereof, etc.

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Mostly agree with Ax. Make sure you have insulation baffles everywhere the sheetrock is applied directly to the bottom of the rafters. That alone could be the problem. Roofer should have cut both sides, but if you have trusses it doesn’t really matter. If you have a ridge board, you certainly will vent one side better than the other. Or, if it’s vaulted all the way to the peak, one side may not vent at all.

I do not like spray foam or insulated panel homes (though I have built them). I think a house needs to breath, we are building em too tight these days.

Hi. in my opinion proper ventilation comes from intake at the soffits a d exhaust at the ridge vent.the baffles are crucial on the cathedral to allow proper removal of heat.thus for the shingles are experiencing less chemical break down as well as keeping the attic space the same temperature as it is outside.this being said faulty ventilation issues can cause the tips of the roof nails to sweat.i was wondering if upon inspection the underside of the roof deck showed any water spots or moisture or water spots around the many roof nails.also I would recommend verification that there is baffles installed in-between the Joists of the cathedral (vaulted) ceiling.also if I understand correctly the exposed nails with no silicone also means the top edge of the shingles at the ridge are too short and if you look the space between the butt joints of the shingles would allow water in.one last thought is the vapor barrier under the shingles.is there a vapor barrier properly installed thus being water flows downward and it should be overlapped from the bottom to the top.basic run of theory.also your cold air return shouldn’t have water in it.there is a ton of things to explore with this…anyway hopefully this was helpful.god bless RAO SUB CONTRACTING.If you have any more questions you can contact me at raosubcontracting2016@gmail.com.my name is Ron

Before you start pulling out drywall can you post a pic of the manifestations you are seeing on the interior.