On 10 Feb 2007 16:18:54 -0800, "Victag" wrote:

We have just insulated our shed and put vapor barrier inside the
insulation, with a layer of tar paper between the insulation and the
siding. We are noticing that one wall is sweating and moisture is
collecting between the insulation and vapor barrier. Berfore we
drywall, we want to eliminate the moisture. The attic of the shed is
vented, so I can not understand why we are seeing this moisture
still? Does anyone have any advice as to how to fix this and why we
would still be getting moisture? We would like to use the shed as an
office and have also installed heating. Are we still lacking proper
venting or is this likely because we have not properly sealed the
vapor barrier? Thanks in advance for any help. If it makes a
difference, we are in BC Canada, moist climate with a mix of cold and
warm.

The problem you describe can usually be attributed to having two vapor
barriers. For example, a poly vapour barrier on the inside and a
vapor resistant sheathing, such as OSB, on the outside.

However, since you state you "just insulated", it is likely there was
moisture in the insulation to start with, and the moisture is
condensing on the poly..

Recommend you slash the poly, let the insulation dry, then repair the
poly using tuck tape and see if the problem re-occurs.

Since you don't have sheathing, another possibility (remote) is rain
getting through the siding on the windward side and soaking the
tarpaper to the point of moisture penetration.

Gary in Royston, BC