Condensation on insulation, open rafters

[audimurf]

Finally warming up a bit today and decided to get the garden ready for spring and set up the patio. I went to get the umbrella out of the garage rafter and saw this. I practically **** myself but appears to be condensation, and a lot of it. The insulation is bone dry as well as the roof.

We bought the house last Sep and this was our first winter in the house, all be it a NASTY one!

I did run a propane heater in the garage a lot over the winter while working in there. Could the condensation be from hot and cold cycles that froze and are finally thawing out?

Is the insulation ruined?

Thanks!






Cell phone pics so the wet areas look a bit darker than they really are.

 

[Steevo]

What is this contraption?;

And . . . Why is there kraft-backed insulation placed directly against the roof sheathing?
Where is the air space?

 

[Krodad]

I think that is a radon evacuator.

Your insulation is wet up at the peak… if you have a ridge vent it's wet mist likely from frost forming up there. Or snow infiltration. I didn't look to see where you live.

Sent from my SCH-I535 using Tapatalk

 

[ddawg16]

You can't insulate the roof like that....you need drywall across the ceiling joists and insulation on that.

The second story of my garage is 'similar'....except I have insulation AND 1" dense foam as the bottom layer....and we get the condensation....

As soon as I'm done with my current batch of projects....we are going to drywall the ceiling....when it's completely dry.....

 

[audimurf]

Krodad got it right, it is a radon excavator. wish the home inspector woulda caught it.

So i need to add foam between the fiberglass and the roof? Off to research, will come back for responses.

 

[Nowater]

Propane heaters pump a lot of water in the air, so they may have caused or worsened your problem. IMO your insulation needs to be replaced if it is wet.

More pix and details could lead to a better suggestion!

 

[Sheriff245]

So i need to add foam between the fiberglass and the roof? Off to research, will come back for responses.

You need air between the fiberglass and the roof, and there needs to be plenty of ventilation to allow that air to exchange and evacuate humidity.

Maybe I'm wrong, but it seems pretty common in the US from what I've seen to just put kraft-backed insulation between the joists. Up here in Canada we always seal the vapor barrier at the joints so the humidity from the warm inside air has no way to escape and condensate in the walls and attic.

 

[audimurf]

I will get better picks tomorrow. I went back out and checked the soffit for the garage and they are stuffed with insulation. That coupled with me adding vinyl weatherstripping to the garage door to keep the chill out kind of made it air tight. I do have vents on the roof but they spent most of the winter covered in snow drift. I will be proactive next year in keeping them clear of snow.

Ideally, I should put up drywall on the trusses but I do not want to loose the storage.

 

[Nowater]

I don't understand what the drywall will do to help your ventilation/condensation problem. I think you need a vapor barrier and or more ventilation. This might be good job to hire done.

 

[alwaysFlOoReD]

You need a vapor barrier between the warm side and the insulation. You also need air flow up against the roof sheathing to carry away any moisture that migrates to that point. The easiest way is to use the bottom chords to hang poly and then fill on top with insulation, then drywall under the poly. The other way of doing it is to have expanding foam [closed cell] sprayed directly onto the roof sheathing, but that can be pricey. Cheaper than replacing a roof tho.

Richard

 

[BFHtime]

When propane burns part of the reaction creates water. The increased warm air and water, increases water vapor. This also causes the once heated air to feel very cold as the temperature decreases.

Consult a professional.

 

[Train]

Coulda swore you said "home inspector". Did he just phone in the inspection?