Insulating a concrete block house
I have a concrete block house that I would like to insulate the exterior walls using foam panels them coating with a trowel or brushable product like tuff II by styro industries.can this be done on the exterior and interior without creating a moisture problem ?which foam panels would be best suited for this application ?the house has concrete slab floors
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Hi TNKC (be great to have a real name to use in a community like GBA...) -
In terms of moisture management of the block walls, there is no reason why you can't insulate both the interior and exterior of a block wall (see the GBA case study of my 100+-year old home where I insulated the exterior with closed-cell spray foam on my first floor un-grouted concrete block walls: https://www.greenbuildingadvisor.com/green-homes/deep-energy-makeover-one-step-at-a-time).
The block has plenty of hygric capacity and, depending on just how cold your climate is, does not care much about how wet it gets. But everything that "touches" the block wall may care quite a bit about how cold and how wet they get.
So, water and temperature management (flashings and insulation/air sealing) at penetrations and assembly transitions are no less important in your concrete block home than any other home.
In terms of the type of rigid insulation: there are plenty of pros and cons for each: see, for example, Martin Holladay's article: https://www.greenbuildingadvisor.com/article/choosing-rigid-foam).
Peter