Our house is located fairly close to a major highway, and a neighbor has an ATV that is quite noisy. We have owned the home for almost two years and plan a kitchen remodel. While doing that, I was thinking about having the contractor (1) replace the insulation in the existing exterior wall, (2) leave the existing wall alone and merely add another interior wall (yes, it would shrink the interior room space a bit), or (3) take the interior wallboard from the existing wall and add noise-cancelling insulation to both existing wall and a new interior wall. The room is not large (really a den that no one uses except me). Has only one vinyl double-paned window.
I have no idea how to approach this project and which insulation I should consider. Any ideas would be appreciated.