Shell with fixed ceiling — When a total acoustical ceiling or fixed ceiling is used in a structure, natural airflow is prohibited. Air must be forced through the ceiling, against the domeís shell by mechanical means, such as an air-handler or a fan system. Maintaining the airflow is a major part of the domeís energy efficiency.

Shell with fixed ceiling — When a total acoustical ceiling or fixed ceiling is used in a structure, natural airflow is prohibited. Air must be forced through the ceiling, against the domeís shell by mechanical means, such as an air-handler or a fan system. Maintaining the airflow is a major part of the domeís energy efficiency. (David A. Collins)