Hot days inside sweats

New pole barn, roof is sheeted in 1/2" plywood then vapor barrier then metal roof, inside there is R19 in the ceiling with white scrim plastic covering the R19. Walls are R19 with Sheetrock on them finished. All was going great until we got a couple sunny days and I started getting drips from inside the roof where it dripped thru some gaps and seems in the plastic on the ceiling. Was told it was cooking the moisture out of the wood and it will quit after wood is all dry? Looking for a for sure reason or fix so I can move my equipment in please help, Thanks		Darin Borg 4/27/2012	Share Or copy this URL: https://www.metalroofing.com/spirit/comment/17356/find/
I wish that the vapor barrier was between the drywall and the insulation, frankly. This could very well be an issue of moisture inside the building reaching the back side of the plywood and condensing. However, you said that the problem occurred on sunny days. Was there a lot of moisture in the drywall for some reason?		Todd Miller Isaiah Industries, Inc. 4/28/2012	Share Or copy this URL: https://www.metalroofing.com/spirit/comment/17357/find/
inside the ceiling is not sheet rocked it just has plywood then r19 then plastic, the walls have r19 then a vapor barrier then sheet rock. Dont have any problems in the walls that I know of?		Darin Borg 4/28/2012	Share Or copy this URL: https://www.metalroofing.com/spirit/comment/17358/find/
That is plausible but you might want to install some ventilation in the barn that is on a humidistat.		Eric Novotny An informed customer is the Best Customer! 4/28/2012	Share Or copy this URL: https://www.metalroofing.com/spirit/comment/17359/find/
Moisture from inside the structure is probably condensing on the plywood when the plywood cools down at night and air inside is still warm. Finishing the ceilings should minimize moisture that reaches the plywood.		Todd Miller Isaiah Industries, Inc. 4/29/2012	Share Or copy this URL: https://www.metalroofing.com/spirit/comment/17360/find/
+1 Get all your air barrier details tight and careful and that shop a majority of the moisture. Air carries 100x as much moisture as diffusion does.		Eric Novotny An informed customer is the Best Customer! 4/29/2012	Share Or copy this URL: https://www.metalroofing.com/spirit/comment/17361/find/

If you would like to reply to this thread, please log in. If you do not have an Ask the Experts forum user account, create one here.