RH problem

[Christopher Thomas]

Typicaly it is simply a plastic sheet of some thickness that is applied
over one side of the wall insulation. Sometimes it is called a vapor
retarder because after it is staples in place it won't stop all
moisture.  Can be tyvek (trade name) or just plastic wrap. Up where you
are, probably wants to be on the warm side.

-----Original Message-----
From: pianotech-bounces at ptg.org [mailto:pianotech-bounces at ptg.org] On
Behalf Of Ric Brekne
Sent: Friday, May 05, 2006 1:02 PM
To: pianotech at ptg.org
Subject: RH problem

Thanks Chistopher, Terry... and Don.

I wonder if you could expound a bit on exactly what a vapor barrier
is... is that like a space of dead air in between double panes of window
glass ?

Terry... about the Farhenheit bit.... I was speaking Amerilish for youz
guys's benifit you see... :)

Cheers and thanks.
RicB

Responding as an architect, I asked a senior technical architect in our
office for his thoughts. He agrees with Mr. Farrell. The building
envelop needs a vapor barrier. If it is a hot humid climate, the barrier
should go to the outside. If it is a cold dry climate, like here, it
should go towards the inside.
------------------------------

My best guess is that the ceiling and upper walls are poorly insulated.
These are outside walls? The dew point for 40% RH and 72 degrees F is 46
degrees. So if it was 36 degrees F outside and the walls were around 40
degrees F or so, condensation will occur on the walls.

I thought Europeans used the Celsius scale for temperature.

Terry Farrell