I would recommend going in to the studs because you have peace of mind knowing that the chair rail will stay up.
If the chair rail is nailed to rock and glued, think hypothetically, if the rail is hit or bumped, the nail will come lose and the glue may let go.
Get a stud finder and take fifteen minutes to locate the studs and walla, your set. No big deal in locating them.
© 2017 Renovate Your World LLC