Originally Posted by High Gear
If I understand right you built a straight wall ground up over your half exposure ?
Then in front of the framed portion you stuffed full of ins.and then added a vapor barrier.
The above ground framed portion should be 2x6 and already insulated to probably r19 or better depending on what they used.
The "vapor barrier" is the house wrap ( which is really a vapor retarder so your walls will "breathe").
I believe using the 6mm vapor barrier on the interior is a big mistake.
The walls need to breath.
Higher humidity is probably from the concrete wicking some moisture from the earth ( normal).
I believe basement moisture should be under 50% with these type walls ( foam/glass) according to building science ( less chance for mold to develop)
You may wish to use a dehumidifier in the basement along with the A/C as needed.
If its not hot enough to cycle the A/C much then the dehumidifier picks up the slack.
Money may be better spent on acoustical tile ect. rather than fiberglass as far as sound reduction goes ( ceiling )
If you have lots of carpeting upstairs you may not have any noise issues , hardwood/ceramic floors yes.
I see no advantage to ceiling insulation from an efficiency standpoint when the basement is living space.
Actually you're wrong on several counts...
-My above ground portion is framed by 2 x 4 and was stuffed with faced R-13. I removed the "faces" and replaced them with a continuous sheet of 6mm vapor barrier. House wrap is not
a vapor barrier. It is a water barrier but moisture/water vapor can still go in and out of it so the wall breaths through it.
-I didn't state that I put a vapor barrier over the fiberglass on top of the foam insulation on the below grade portion. Just fiberglass, no vapor barrier on it because the foam insulation is a vapor barrier itself.
-Soundproofing-wise, don't sweat it. I'm doing many more things to soundproof the ceiling, including using much thicker drywall to add mass (a total of 1-1/4" thickness), decoupling the ceiling from the joists using clips and hat channels and then using a sound dampening chemical between the drywall. For what I am doing, adding fiberglass in the joist cavity is absolutely essential to achieve complete results. (see http://www.soundproofingcompany.com/...oise_ceilings/
The moisture must be coming from the concrete floor which isn't sealed. I sure hope so. I'm doing a lot of different things here to ensure that I won't need a dehumidifier. Looks like I am pretty close to getting to 50%, I'll probably be there once the floor is sealed. It makes much better financial sense to spend a little more now with a one time cost than to just do a "contractor grade" basement finish with an on-going cost (electricity for dehumidifier).