Insulation on exterior and interior
My house was built in 2009 in climate zone 6. It has a poured concrete foundation with R-5 XPS exterior insulation. Currently there is no insulation on the inside.
I am planning on finishing my basement and am curious on what the best way to insulate the interior would be. I spoke with my city inspection department and got some conflicting information on energy code compliance. One inspector advised not to add any additional insulation and the other advised 1″XPS with a 2×4 uninsulated studwall was sufficient but the XPS was not totally necessary.
As i understand it i have to me R-15 ci? This would imply 2″ XPS on the inside? Would it not be a good idea to have some additional rigid foam on the interior surface?
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