Homeowners and designers often desire cathedral or vaulted ceilings because of their aesthetic appeal and added height to a given space. But if a home is located in a heating climate zone—where a building's interior generally is heated for a longer portion of the year than it is cooled—problems such as ice damming may arise because cathedral ceiling roof systems are difficult to ventilate.
However, there are ways to achieve proper ventilation and minimize ice dams' effects.
A cathedral ceiling is considered a compact, or "warm," roof assembly, which means each roof system component is in direct contact with the preceding component; therefore, there is no attic space between the ceiling and roof deck. These types of roof assemblies present particular ventilation problems, especially in heating climate zones. The problem most associated with unventilated, improperly insulated cathedral ceilings in cold climates is ice dams.