‘Best’ exterior wall insulation technique?
1. Definitely want to use insulation between the brick and sheathing. Are the products that are attached to the sheathing in one sheet better at insulating and/or cheaper than the foam boards (or something similar) and regular sheathing?
2. If you use closed cell foam (CCF) on the inside, do you still need the wrap on the outside?
3. If you only use enough CCF for air and moisture barrier, can you apply open cell on top of the closed cell? Is there a particular CCF that is more eco-friendly regarding greenhouse gas emissions.
4. How do you determine the cost/value analysis of 2×4 with CCF, 2×6 with CCF and batting (denim, cellulose, or fiberglass?), or 2×6 with CCF and OCF if that is possible?
We are having trouble affording the house we want to build, so I have to take cost into account. I would like to do 2×4 walls with the continuous exterior panels, an inch or 2 of CCF and the rest with OCF. Or, would we get enough energy efficiency improvement of going to a 2×6 wall that it would make up the difference in construction cost?
Too many options – and this is before I even get to the cathedral ceiling or the attic!!!
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