insulation moisture??

[Rich]

Hi all -

I recently insulated my attic. To do that, I removed the plywood floors that were nailed to the floor beams. I then installed R-38 faced on the attic floor but not the rafters. I am now noticing that after replacing the plywood (on top of the insulation), may places are showing damp spots and are moist to the touch...what can I do to stop this other than perm. removing the floorboards?

Suggestions?

Thanks.

[hallerb]

you need better attic ventilation, think ridge vent, or power vents controlled by humidstat

[Joseph Meehan]

Where are the damp spots? On the ceiling below, on the top of the floor, around vents on the roof???? You installed the insulation correctly, but there may be air leaks below it.

[cavedweller]

I pictured condensation dripping from the now colder roof onto the plywood floor. Perhaps the OP could clarify.

[websurf1]

I'm picturing moisture going through the ceiling drywall or holes in the drywall for lights, etc., through the insulation, and into the wood.

If the house is in a relatively cool/cold climate, there should be a vapor barrier on the WARM side of the insulation, to prevent just this sort of thing. Assuming, of course, that what I am picturing is closely related to the truth....

[Rich]

Thanks for all the responses.

The moisture is on the floorboards, and it doesn't appear to be coming from the celing at all. I walk up to the attic to find spots on the floor that are wet on the plywood foor. The only curious thing is it only happens on the side of the attic where our window is...which led me to believe it's a venting issue...the window leaks like crazy.

[cavedweller]

Do you mean the ceiling below, or the ceiling above? I'd still be looking up at condensation points on the inside of the roof....nail points maybe.

[ransley]

Depending on what is wet you need a proper vapor barrier or better attic venting, probably both.

[trader4]

Agree. And from the description, I'm not sure where, if any, the vapor barrier is. The statement "I then installed R38 faced on the attic floor....", leads me to wonder if the insulation has a vapor barrier and it was installed against the attic floor, instead of the ceiling below. There should be one vapor barrier, at the ceiling surface in the attic.

[Rich]

Sorry I was too vague - the r38 insulation is on the attic floor, which is the celing of the 1st floor (ranch-style)...the vapor barrier is between the attic "floor" and the 1st floor "celing." Does that help? Thanks.