Storm windows and caulk

[Andreas W.]

I plan to install a storm window and want to run a line of caulk between blind stop and storm window flange. The caulk's purpose is to reduce air infiltrartion. Any idea what material stays pliable so that the window could get removed again in 10 years or later without tearing the window apart?

[Jim Adrian]

I think you over thinking this in general and not worth it.

A  non-curing butyl sealant.  Typically used in roof applications. It needs to be a non-sag (NS) product otherwise it will run on you and leave streaks on the wall.  You wont like the results of this.   You may be better off with a clear or white acrylic sealant right at the edge of the frame.