For installation of a chimney in a cathedral or pitched ceiling such as standard A-frame construction. The Pitched Ceiling Support Kit provides all necessary parts for a complete installation with the exception of the required Insulated Pipe Lengths and Adjustable Flashing (AF). Selection of the Adjustable Flashing is determined by the pitch of your roof. In calculating the number of insulated Pipe Lengths your chimney run requires, note that the Roof Support Package (RSP) comes with one 18 inch pipe length as part of the support.