Replies

1. 
   unclemike42 | Apr 29, 2021 02:59pm | #1

   https://insulationinstitute.org/im-a-building-or-facility-professional/commercial/installation-guidance/managing-moisture-in-commercial-construction/vapor-retarders/

   You are far enough south that a hard vapor barrier on the inside could lead to moisture problems, when warm, humid air from the outside (and moisture that has penetrated the masonry walls) condenses during the cooling season and cannot escape.

   If you are opening up to the studs, rock wool is a good choice.

1. 
   gakoid | Apr 29, 2021 03:10pm | #2

   Thanks for the advice. I am building the new stud wall against the exposed concrete block so I have an opportunity to provide any vapor barrier and insulation that is needed. I was considering applying a painted sealant on the block wall. Is your advice NOT to have a vapor barrier? Thanks so much.

2. 
   unclemike42 | Apr 29, 2021 05:38pm | #3

   https://www.com.ohio.gov/documents/bbst_ResidentialCodeofOhioEffectiveJuly1,2019.pdf

   Good advice is to contact your local building codes office and find out what they advise and will require.

   I would be inclined to go with a good latex exterior paint on the inside of the block, on a latex primer. special care to make sure the block wall is sound, repairing any cracks and sealing penetrations. Purpose is mostly for air sealing, while not being a too-tight vapor barrier.

   If you find moisture evidence, take time to remedy the intrusion source.

   Since you have it open, a great time to make sure the rim joists for the floor is sealed and insulated as well. Same for the second floor.

3. 
   andy_engel | May 05, 2021 06:49am | #4

   You live in a climate where the vapor drive is reversible. In summer, it's likely inward. In the winter, it's likely outward. I'd consider either a smart vapor retarder on the inside (https://www.finehomebuilding.com/project-guides/insulation/smart-vapor-retarders-for-walls-and-roofs), or I'd treat the assembly like a basement wall (https://www.finehomebuilding.com/2005/03/01/the-no-mold-finished-basement).