Certain precautions should be taken when installing cellulose insulation.  The following are important precautions and limitations to always remember.

Heaters and recessed light fixtures must not be covered by the insulation, unless the fixture has an IC (insulation contact) rating.  A minimum of 3 inches of air space must be maintained between fixtures and the blocking.  Always follow local and national codes if applicable.

Cold air returns and combustion air intakes for hot air furnaces must not be blocked or insulation be installed in a manner which would allow it to be drawn into the system.

Insulation must not contact chimneys or flues.  A minimum of 3 inches of air space must be maintained with blocking used to retain the insulation.

The homeowner should be advised that in tightly constructed homes or when insulating existing homes which have fuel fired heating systems within the living area or basement, an air duct must be installed between the furnace room and a well ventilated outside area to provide combustion air.  A local heating contractor should be contacted for proper duct size and installation.

Installers and specifiers are advised to refer to other relevant documents, including the National Electrical Code, ASTM Standard Designation C1015, CIMA Technical Bulletin #1 Cellulose Insulation: Codes, Regulations and Specifications, and CIMA Technical Bulletin #3 Standard Practice for the Installation of Sprayed Cellulose Wall Cavity Insulation, for additional information.