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codensation on walls-1920 house

So what is the deal?
In winter, walls have condensation on them.
This is because they aren't insulated, right?
If I tear down the walls and insulate then sheetrock
it will stop, right? Right now plaster walls in a 1920
farmhouse. Have new roof and 9" blown insulation in the attic last year as
soon as we moved in. This is next project. One room at a time.
I could blow in insulation but would like to rewire at same time.
One room at a time. Any thoughts? What about mold? Is there a can
of worms behind these walls?

Re: codensation on walls-1920 house

Warm moist air hitting a cold surface you get condensation. You are less likely to have a mold problem with the plaster and lath plus plaster walls will generally out last drywall.

High humidity may be the problem, ventless gas logs, if you have them, or gas stoves with no vent hood, output a lot of water vapor. You might want to consider dehumidifier.

Timothy Miller
Re: codensation on walls-1920 house

Adding the attics blown in insulation may of created the additional humidity in the walls that use to migrate threw the attic.. I have read that cellulose insulation in the walls is not to have a vapor barrier when it is used- cellulose web page. If you have a humidifier on the furnace consider turning it off. As for mentioned a dehumidifier might also be a good choice. What type of insulation did you have blown in? I would suggest in the summer to have cellulose blown into the wall cavities too...

Re: codensation on walls-1920 house

What kind of heating system do you have---and has it been cleaned & in good shape???

How about the chimney & the things JLMC advised you to check???

Are any family members complaining of headaches or flu-like symptoms??

I would buy a carbon monoxide detector ($20) if I had wall or window condensation---small price for the peace of mind!

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