Controlling Humidity in an Old Basement
I have a Victorian house in western Massachusetts that was built in the 1880s. The unfinished basement is 1,700 square feet. And one of the rooms of the basement is problematic. It is 234 square feet and the concrete floor is all busted up, the floor is always damp, and the room is constantly humid, over 60% RH.
There is a French drain along one wall in that room which leads to a sump pump. There is also a French drain channel that goes from the middle of the room to the French drain against the wall.
The walls of this room are field stone and then brick. Once in a while water seeps through the wall in one place right where the French drain is located.
We rarely go into this room so I currently have plastic on the floor in an effort to reduce humidity. I know I should tape the seams of the plastic on the floor to better seal in humidity. But I can’t decide what to do about the walls.
If I encapsulate the walls with plastic sheets or another vapor barrier (assuming I use caulking to create a tight seal on the wall), then wouldn’t moisture be trapped between the stone/brick and the newly hung plastic? Wouldn’t that be bad for the brick and stone over the long term?
I was thinking of painting the wall with Drylok (using their etching and cleaning product first) but then read an article about how to fix historic brick and stone walls which recommended against painting the walls.
In this room I have a GE dehumidifier, Model APEL509LZQ1, 50 pints a day. In another part of the basement I have another dehumidifier, Frigidaire, Model LAD704TDL, 70 points a day.
In retrospect I should have bought one E-series Aprilaire dehumidifier for the whole basement.
So… does anyone have any suggestions on what I should do about the problematic room? (please note: I am in the process of trying to prevent water from seeping inside the house. I am planning to have a landscaping company grade around the house and install a french drain along the parts of the house where water sometimes seeps in.)
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