Insulating a 1905 vintage 2-1/2 story
Greetings. I am in the process of “rescuing through renovation” a 1905 vintage 2-1/2 story house in Omaha (zone 5) that was formerly divided into seven apartments. Being that the house was used for apartments for the last 50 years, it has received minimal maintenance. The weak condition of plaster on the inside of the exterior walls have made the decision to gut the walls of plaster and lath a clear choice. I have new windows on order to replace the existing deteriorated windows.
As one can guess, there is no insulation in the side walls. Unfortunately the renovation budget and likely property value can’t justify using double-framed interior walls. Since the walls will be totally accessible I plan to use “flash and batt” insulation to minimize air infiltration and have a wall with something close to an R-20 rating.
My main concern is the roof insulation. The attic has completely finished walls and ceiling and was used as on of the seven apartments. I would say 90% of the attic has finished surfaces. Since I’m gutting the second floor walls and ceiling, and am not sure of the insulation in the roof, which of the following would be the best course?
1 Insulate the ceiling of the second floor so that I’m sure of some level of insulation, Would this require a vapor barrier?
2 Bite the bullet and rip out the ceiling in the attic and insulate. This would probably require closed-cell foam to achieve something close to R-45 to R-50.
3 Do both.
Thank you in advance for any thoughts you may have.
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