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Zone 6 pudding stone foundation/interior basement insulation?

BugOutBoy | Posted in General Questions on

Weather destroyed basement door and during the refit, black mold was discovered in the drywall and metal studs.

Building is a 3-story condo building, originally built to house 3 families from Germany working at the old Hosenreffer Brewery. (now Sam Adams).

As for the interior pudding stone foundation:

Should we skim coat it to provide a flat surface for whatever we use as insulation?

Or, if we use a closed cell foam, will the product adhere to the very uneven surface?

Should we once again use metal studs, or should we use wooden 2×2’s?

What kind of air or moisture barrier, if any should be used?

My unit is on the first floor but includes 1/2 of the building’s basement that is the entire width of the footprint going back 1/2-way into the building.

The basement is freezing cold in the winter and suck all the heat out of the first floor. In the summer, it’s nice and cool and reduces my AC usage.

It may be obvious from all the questions that I’m completely confused, but thanks for your help.

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  1. Expert Member
    Michael Maines | | #1

    Closed cell spray foam should work fine for you, as long as you have never seen liquid water running down the walls. The foam will leave tiny gaps that will allow some water to drain. You may increase your air conditioning bill a bit but the savings on your heating bill will be several times higher.

    If you care about the environment, it's important to insist on closed cell foam with an HFO blowing agent, which is a much less potent greenhouse gas than conventional HFC blowing agents.

    The foam will need to be covered with an intumescent coating for fire protection. It just looks like white paint.

    There is no need for additional membranes for air or water vapor control.

    If you want smooth, flat finished walls in your basement, you should frame them first, with either steel or pressure treated lumber, holding them off the stone by an inch or so. Then spray foam the bays, and finish with drywall or the material of your choice. With this approach you don't need the intumescent coating. But it will cost more.

  2. Expert Member
    NICK KEENAN | | #2

    I believe it was the Haffenreffer brewery.

    1. BugOutBoy | | #3


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