My Catalina 36 came with a “southern two piece” cover, meaning just long enough to be 2-3 inches above toe rail. I assume for ventilation. Boating on the upper Mississippi River (straight East of Rochester, MN) where boats are on the hard for six months, I like protecting gel coat from ice, minimizing UV exposure on hull, I had Ship Shape from Duluth extend the top covers to go one foot below toe rail, build a two piece skirt that covers the water line and a walk out transom cover. Takes 4-5 hours to go on, it gets easier every year. Takes patience, following Ship Shape’s instructions and a sturdy ladder. IMHO, worth it to protect the investment. Ship Shape was very accommodating and knowledgeable. Have a nice web sight with install video.