Basement Humidity - 70% Ok?

[RoBoTeq]

Even with having gone through the end of one cooling season and almost a year it could still very well be an issue of the moisture in the building materials settling to the basement walls. I have seen some homes during wetter seasons that take longer to dry out from the initial construction.

My guess is that your cold water lines and supply ducting is sweating like crazy.

[flyboy917]

Originally posted by uktra
Do yuou have a thermostat and return in the basement? Are the basement walls insulated? With what?

No thermostat in the basement. Yes air return. No insulation on the concrete walls as the basements not finished yet. The wood frame wall is insulated with R-13

[uktra]

Insulate the walls with foam board. This is a vapor retarder but will still let the concrete wall dry to the inside. This should help. It does take a while to dry out materials from new construction, so a dehumidifyer may be needed for a short period.