Two months after having my attic professionally air sealed and insulated, the basement floor became damp and the top of the foundation started to show signs of horizontal cracking. Humidity levels in the living space are also high. The house is a one story ranch with a brick veneer. A gas hot water heater and dryer vent were also added to basement.
Basement floor is damp and the top of the foundation is cracking after air sealing the attic
foundationhumiditymoisture
Related Topic
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Best Answer
Horizontal cracking? That's odd, and I think that's unrelated to your moisture problem (even with a picture, I'm not sure I'd comment on that).
Well, you've air sealed your house, which means that now you have to actually pay attention to the
V
in HVAC: Ventilation. In a hermetically sealed house, I strongly suggest seeking a better filter system.I'll take a wild guess that you lack a suitably sized fresh air intake for the furnace, as well as a make-up air inlet for the house (because most houses don't have either).
But you probably just need to look into buying a dehumidifier. Assuming that none of your power-vented equipment is over powering any of your gas-fired natural draft equipment, or that any other item like a fireplace is doing so (hopefully your CO detector will notify you of that).
Your A/C is over-sized or improperly charged. Have a tech come out to diagnose the unit. Hire whoever can explain the difference between superheat and subcooling to you, and what a wet-bulb temperature is.
And explain to them that, you need the A/C unit tweaked to run longer, whether it be from reducing the fan speed, or monkeying with the pressure to make it less efficient, with the goal being to drop out excess moisture from the air.
Central AC system not reducing the humidity in the air? –dslreports.com
The thread goes on about relative vs. absolute humidity for a while...
However if it's not all that hot outside but it's really humid, "Agreed with others in that you are sort of in the 'screwed zone'."