# attic moisture



## altann (Dec 20, 2011)

I have a 2 year old addition complete runs of soffit vents with proper vents two feet r38 of insulation in attic cobra mesh ridge vent and my attic is covered with moisture. Could the ridge vent mesh be nailed down so tight that no air can get out of ridge and by this not allowing air to come in? I plan on replacing ridge vent soon its all I can think of to solve this problem. 
ThanKs


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## Windows on Wash (Aug 30, 2011)

altann said:


> I have a 2 year old addition complete runs of soffit vents with proper vents two feet r38 of insulation in attic cobra mesh ridge vent and my attic is covered with moisture. Could the ridge vent mesh be nailed down so tight that no air can get out of ridge and by this not allowing air to come in? I plan on replacing ridge vent soon its all I can think of to solve this problem.
> ThanKs


100% yes.

Get it off right away and replaced with a proper ridge vent (assuming your intake air is not blocked).

This will be about the 3rd home I have seen this happen on via the threads and one that I personally observed with a huge mold plume on the sheathing.

Get it off ASAP.

Get your roofer out there to warranty the work.


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## altann (Dec 20, 2011)

Windows on Wash said:


> 100% yes.
> 
> Get it off right away and replaced with a proper ridge vent (assuming your intake air is not blocked).
> 
> ...


Thank you roofer is coming tomorrow what a mess in the attic all plywood is wet. Soffits are clear I spend a lot of time making sure all vents and insulation was good the roofer put the ridge vent on.


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## altann (Dec 20, 2011)

Once ridge vent in replaced will attic dry out on its own?


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## Windows on Wash (Aug 30, 2011)

altann said:


> Once ridge vent in replaced will attic dry out on its own?


In the case of the attic that I looked at last week, it had nearly dried out in 1 day.

It still required some treatment of the mold to make sure the spores were killed but it was nearly dry in about 24 hours.


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## altann (Dec 20, 2011)

*attic moister*

Thanks much for your imput. I have a roofer coming tomorrow weather to bad today maybe that cobra mesh is OK for a small attic but not good for a large one. I had someone last night with flashlight held at soffits and the light could be seen in attic through proper vents so soffits are open but ridge vent is not so no air coming in. Its like closing a window.

Thanks


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## Windows on Wash (Aug 30, 2011)

altann said:


> Thanks much for your imput. I have a roofer coming tomorrow weather to bad today maybe that cobra mesh is OK for a small attic but not good for a large one. I had someone last night with flashlight held at soffits and the light could be seen in attic through proper vents so soffits are open but ridge vent is not so no air coming in. Its like closing a window.
> 
> Thanks


The Cobra vent is okay...when installed properly. That is the issue. It can very easily be installed improperly and you wind up with a problem like you have now.

Put a rigid venting (i.e. GAF snow country, OC's system, etc) cap on there and you will be fine.


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## altann (Dec 20, 2011)

Yes that is what will be going on. Bad day to be on roof today icy out there in northern NH can't wait to get this corrected so I can get some sleep haha.

Thanks


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## shazapple (Jun 30, 2011)

You should check for any air leakage as well around light fixtures or holes in the vapour barrier. If there is a bathroom vent make sure it is vented outside (preferably not though the soffit)


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## altann (Dec 20, 2011)

Can lights and bathroom fan pipe are all covered well with insulation. Its just dead air uo there no air movement. A smoke test done to the underside of the ridge vent shows no smoke going out. Also where the mesh meets the plywood roof its very tight on it.

Thanks


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## Windows on Wash (Aug 30, 2011)

altann said:


> Can lights and bathroom fan pipe are all covered well with insulation. Its just dead air uo there no air movement. A smoke test done to the underside of the ridge vent shows no smoke going out. Also where the mesh meets the plywood roof its very tight on it.
> 
> Thanks


Insulation with an air barrier is not going to cut it.

Get them sealed up and boxed out. The lessened moisture will help the roof dry out faster.


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## dougp23 (Sep 20, 2011)

Are your proper vents crushed or blocked? I have seen an attic where an overly eager insulation installer woud slide the proper vent trays in AFTER installing insulation. You coud shine a flashlight up each bay and see about three feet in a huge wall of insulation blocking all that air coming in from the soffits.


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## altann (Dec 20, 2011)

Proper vents where installed first the best kind that bends at end and staples to top of wall. I used a flashlight 2 days ago and looked down proper vents the inside of the overhang trim can be seen because of the painted inside face so it seems its open. Also had someone shine flashlight into so fit vent and the light can be seen from looking down from attic. Again I believe that if the ridge is not open air can't get out so air will not come in.
Thanks


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## altann (Dec 20, 2011)

*attic moisture update*

Well today the cobra mesh ridge vent has been replaced. When removed it was filled with water no spacers where used it was nailed down tight onto the edge of the plywood at the opening closing it totally off. A lantern wick was used (not lit) and the smoke pulled right up through the soffit vents after the new vent was on. Even with spacers I would NOT use the cobra mesh ridge vent it is junk. Thank you all for all of your inputs and advise.

Al T


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## altann (Dec 20, 2011)

*attic moisture now frozen*

OK attic vents have all been corrected soffit vents and ridge vents are all working and the attic is now as cold as the outdoors. I looked up there today one week after fixing vents and all the moisture has stopped but its a little frosty up there will it dry out in cold weather?
All that moisture must have frosted over. 

Thanks


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## Gary in WA (Mar 11, 2009)

Perhaps when it warms up......

http://www.buildingscience.com/documents/insights/bsi-049-confusion-about-diffusion

Gary


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