Take a wire brush to entire surface of crown to remove debris that prevents adhesion, apply duct tape around the perimeter of flue tile (one inch above the crown), apply duct tape around perimeter of crown base (clan edges), repair any minor cracks on crown with exterior silicone or acrylic caulk, set of 10-15 min until tacky, apply 2nd heavier coat-smooth, remove duct tape,

Clean tools with soap and water, Dries to the touch in 30-60 mins cures in 2-3 hrs, requires no mixing special bonding agents (are cure), 1/2 gallon covers 2 coats on a typical crown of 10 feet, clean tools immediately after each use by scrubbing with brush and water, applying in hotter weather may cause to set quickly and make soothing difficult, simply mist surface with water spray bottle to help spread and work easier, elastomoic product, it remains flexible over time prevention further cracks from occurring due to elementally caused expansion.