Insulated Garage was it done properly?

[Bryce188]

My Dad's 2.5 car detached garage was insulated with fiberglass rolls and then plastic vapor barrier (5 years ago). Which is all covered by OSB now. Garage is now heated (Last 2 years) never below 50 degrees F. The problem is there is a lot of moisture in the roof insulation. Does the roof insulation need vapor barrier as well? Have spent the last two weekends pulling down roof insulation and installing dura vents. There is currently soffit venting but no ridge vent. Will adding a ridge vent in spring fix this issue? or do I look for solar powered soffit vent fans? Any information would be appreciated.

 

[Bryce188]

Forgot to mention it is in Southeastern WI

 

[930dreamer]

Does the roof have any passive vents?

 

[The Cobbler]

no venting is the problem.

 

[Bryce188]

No passive vents in roof.

 

[Azu]

I have something similar in my garage: sheetrock, vapor barrier then insulation on top of the barrier.

You need some kind of vent in the roof, be it a ridge vent or a roof vent (or 2 roof vents depending on the square footage of the garage), so the air from the soffits can flow up through the attic area and carry out any moisture (I am assuming the dura vents you are installing are to keep the insulation away from the soffits to allow for air movement from them). You did the right thing with the dura vents. Follow it up with some kind of passive roof vent and you should solve the moisture issue.

 

[Azu]

Forgot to add: if it's really wet up there, you may want to consider removing the old insulation and installing new stuff to avoid any potential mold issues. A bit of a pain, but not too expensive and you would head off any potential health/resale issues.

Best of luck.

 

[jvitez]

What type of roof is it, hip, gable, mansard, shed?

You need to ventilate the air above the attic insulation. The attic air space should be the same temperature as the outside air. You'll need soffit vents for air ingress and ridge or mushroom vents for air egress.

 

[p_mori7]

Need this

 

[Bryce188]

It is a gable roof with no attic. Insulation is between trusses. That is why I was thinking ridge vent so each truss could vent. As far as replacing wet insulation I agree with changing it but it is not my decision. He wants to see if it drys out and is OK. Which I am fine with (for now) since after installing vents and waiting a week insulation is still wet. Why install new insulation if the root of the problem has not been fixed.

 

[mygarageone]

It won't dry out especially in the winter months .

 

[bczygan]

When summer comes, open the garage door and run fans to dry it out.
Install ridge vent and make sure there is an airspace from eave to ridge in each truss space.

Then provide a vapor barrier on the warm side of the ceiling. This could be a vapor barrier paint, if drywall is already up.

 

[raceman6135]

Then provide a vapor barrier on the warm side of the ceiling. This could be a vapor barrier paint, if drywall is already up.

If it's cost prohibitive to buy specific vapour barrier paint, you can use 2 coats of a good quality alkyd (oil) paint to serve as a vapour barrier.

 

[Scott H in Wheaton]

So insulation is tight up against the roof decking?

I think you could benefit from an air gap between the insulation and the roof deck. Take down insulation, install soffitt baffles over entire roof deck, ridge vent at top, re-install insulation.

 

[Bryce188]

Scott that is what we have done minus ridge vent until spring. As far as the vapor barrier never really thought about for ceiling. There is no drywall so putting up plastic sheeting shouldn't be to difficult.