Condensation on bedroom ceilings in winter
I live in Chicago. I have a masonry/frame 2 story house that’s 33 yrs old. I have R-25 fiberglass insulation in the attic, R-13 in the walls. I had my upper story exterior cedar siding replaced in 2011 with James Hardy board. The house was wrapped with Tyvek before installing the cement board. Ever since this was done, I’ve developed condensation above each soffit vent located above windows and also on one an exterior ceiling wall without a window, but does have a soffit vent above it, located on the north side of the house. This one is the worst and actually has water droplets on the ceiling the others get frost.
I know my windows being 33 yrs old and major air leaks was a portion of the cause, so I just replaced 16 double hung windows with new ones with better insulating value. They also foamed sprayed around the cavities so I’m hoping this makes for a air tight seal.
I was keeping my thermostat around 56-58 degrees during the winter in this upstairs portion of the house and the lower level at 64-66 degrees in the winter. Now I’m going to keep the upstairs at 62 all the time, in hopes that this will correct the problem of the condensation. I have a automatic humidifier on my gas furnace that I keep at a bare minimal setting.
I had a blow-door test done just recently, and yes there are many air leaks along the top plate and wall plates, but my overall reading was 1710. So on a scale of 1-10 my house is like a 7-8 and pretty tight. If I have all the air-sealing and more cellouse insulation blown into the attic to raise it to an R-49 for my region, like I wanted, I’m told I will now need a EVR installed to insure fresh air. I don’t want to install one and they are very expensive and no room in my basement to put in by the furnace.
I’ve been told in the past by my roofer, to run my power thermostat/humidistat fan 24/7 forever and this will help. Now I’m told by the energy auditor not to use it. Besides what I’ve read on your website.
I’m confused. but mostly I want the condensation to go away.
Please, do you have any advise I can take away and live without my ceilings being ruined or take a chance of mold developing in the attic?
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