This weekend is the time so I’m down to one last question. Should there be a vapor barrier between floors (1st to 2nd)? I’m wondering, since the floor will be colder than the ceiling below it (radiant floor excluded).
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I don't normally see a vapor barrier between two heated finished spaces, unless one of them was being tiled, but that was for waterproofing not a vapor barrier.
When asked why is there four engines on a 747------ "cause we couldn't fit six" a Boeing engineer
I couldn't think of any reason to put a vapor barrier between floors in a single family home that is heated and cooled as a single unit. I also reviewed Joe Lstiburek's - Builder's Guide To Cold Climates, and couldn't find a reason there either.
Randy
Edited 10/27/2006 9:09 am ET by Reg
Thanks.
No point, if both are served by essentially the same air-handling system. A vapor barrier is only needed when the temperature on the cold side can dip below the dew point of the air on the warm side for days or weeks at a time.
if your have minium 5/8 t&g ply subfloor it would be considered equal to vapour barrier even if you were looking at 1st floor above cold crawl space.
About the only vapor barrier between floors that makes sense would be over a bathroom. I like to install a vapor barrier completely around a bathroom to keep water vapor from leaving the room anyway except for through the vent.
Beer was created so carpenters wouldn't rule the world.