# Moisture behind the FG blanket...



## Windows on Wash (Aug 30, 2011)

Around the beam is pretty normal. Probably just difficult to get the plastic sealed up and around.

Check to make sure outside is not weeping and letting bulk moisture price.


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## Amitabh (Oct 21, 2010)

what do you mean by "letting bulk moisture price"

i am going to check outside tomorrow...

is the moisture in the pictures normal?


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## Amitabh (Oct 21, 2010)

Its gone! The moisture is gone! I left the concrete walls uncovered over night and all the moisture is gone this morning. the walls no longer feel clammy and wet, but dry. 

The humidity level is also 28% in the basement now. 

I think this is a good sign right? With the plastic vapour barrier gone, the concrete walls are breathing. Now, i will glue the foam boards and that should make the overall situation better, right?


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## Windows on Wash (Aug 30, 2011)

Plastic vapor barriers are a nightmare if they aren't done 100% perfect.

Start with the rigid and be sure to seal up and insulate the bands and you should be golden. 

Leave an inspection area if you have any termite concerns (not sure Canada does).


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## Gary in WA (Mar 11, 2009)

Are you sure that centralized moisture is from the interior, could you pull the 2x and look behind it? Did you check your siding outside? Pull some vinyl,(if) and check the WRB to extend down past the mudsill plate onto the concrete wall? Is water entering at that joint? Did the poly have any big gaps where the moisture is located before you pulled it off?
Cut/lift the sticky sill sealer where it hangs inside, wet under there?

Gary
PS. you cannot "dry fit" fb and leave it there without gluing it and air-sealing the perimeter/joint or moisture from basement humidity will condense on the colder concrete wall under the foam board.


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## Amitabh (Oct 21, 2010)

Hi Gary

I will double check the mud sill and the bolt this weekend. I do remember checking these areas when we saw the moisture and noticed that it was dry. Also the area above it was dry.

What do you mean by "pulling the 2x"? what is "WRB"

We dont have siding, just a brick house and the concrete wall goes above the around at least 1 ft on the outside before the brick starts.

what you saw in the pic is the moisture that we found. There was one more area, i forgot to upload the pic, but that area has dried up as well..

I had glued the boards to the concrete walls sunday evening. and will tape this weekend the joints.

i got two kids and they run a muck... you should have seen what happened tonight. Going to post that in electrical i think.


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## Gary in WA (Mar 11, 2009)

If that thin foam board is rated at R-5, and you frame a 2x4 wall in front, the foam will be at 4C and 35%Relative Humidity above grade and couple o0f feet below grade for your 3 coldest months averages; http://www.worldweatheronline.com/Toronto-weather-averages/Ontario/CA.aspx RH higher than that will condense in the cavity on the fb and insulation/wood framing. With R-10 XPS and R-15 Roxul, temp will be 7C and 43% RH, much better for the coldest time of year. IF using the thinner/and it is only R-5 XPS (1") be sure to control the basement RH during that spell...

I was referring to the wood horizontal piece below the white (drywall?) in last picture- to remove and examine under- not if it is attached structural framing.

Gary


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## Amitabh (Oct 21, 2010)

thank you everyone... 

double checked the area and it was all dry.


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