A.Master electrician Rex Cauldwell responds: You’ll have to use the exposed cover plate. By code, you must leave access to any splice anywhere. (The only exception is an irreversible crimp on a service entrance cable — a special case requiring an expensive crimping tool.) Splices in attics and crawlspaces are considered accessible as long as there is a hatchway into the space. Even these splices must also be in a box and behind a cover plate.
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