Remember to cover fan motors, switch boxes, outlets and other electrical equipment before washing down the house. Clean these types of equipment with a blower, dry brush or rag before covering them. Start at the top of the house and work down. It is critical to do a good job removing dust, dirt, litter and manure from the house. Be sure to clean off ledges, braces, air inlets and all other places where dust, dirt and litter accumulate.
Most disinfectants are less effective if used in the presence of organic material.
The dust, dirt and fecal material tie up the disinfectant that would otherwise be available to kill the microbes that cause disease. All disinfectants work best on a clean surface. Fumigants have been used in the past to disinfect poultry houses. Today, there is some concern over the safety of many of these products as some are quite toxic or carcinogenic. Take great care when using fumigants.