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TOPIC: Condensation Issues

condensation

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I live on a canal in New Jersey, fairly humid area. The back section of the house(40x12) only has a one foot crawl space with r19 hard foam insulation. The ceiling is old ship lap barn boards , so warm air still escapes. There is some condensation dripping through the sheathing at a seam and an screw hole in the middle portion of the roof. There is no other evidence of condensation in any other portions of the roof. This middle room is also at the top of the stairs and across from the bathroom, excess heat and moisture. Would spray foam insulation on the bottom of the sheathing act as a good vapor barrier? I am guessing that the warm air is sneaking up through those gaps and holes. Thanks for your help.
Guest User

1/17/2007
I think you are on the right track.
Allan Reid
Dura-Loc Roofing Systems, Inc.

1/19/2007
would pink baffle on the bottom of the sheathing and a plastic vapor barrior on the ceiling work. then blow loose insulation into the remaining area. it would keep moisture to a minimum and give approx r25 between the ceiling and the baffle. our access is limited. the spray foam would be very difficult. do you think that this would work?
Guest User

1/24/2007
Your biggest problem is heat loss which then condensates on the bottom of the metal. More insulation helps a but you truly need an interior air barrier and exterior underlayment. Foam will cure both.
Allan Reid
Dura-Loc Roofing Systems, Inc.

1/25/2007
I found a couple of spots where the new roof meets the old roof and there is a gap in the sheating. I can reach up in the crawl space and touch the metal roofing. If I cut 2" thick stiff polyfoam insulation and filled the area; then sealed the seams with spray foam' would that help. Just below these areas are the only places That I am getting condensation dripping. Thanks for your help.
Guest User

3/6/2007
If you can seal off the heat and moisture it may work, yes. Todd Miller
Todd Miller
Isaiah Industries, Inc.

3/17/2007