Mushroom Cap Attic Vent

• 1). Measure the attic in cubic feet. Select the exhaust fan recommended for efficient exhausting of hot air from the attic. An HVAC professional or home building specialist can be of assistance; two or three fans may be required. It is preferable to have two fans working intermittently than one fan running constantly.
  
  
• 2). Locate a spot on your roof where you want the roof-mounted power exhaust fan to be installed. The higher on the roof and closer to the ridge, the better. Hot air rises to the fan.
  
  
• 3). Check the manufacturer's specifications for the required size circuit breaker. In most cases, a 20 amp breaker and #12 wire is recommended. Run a power feed from the service panel to the location where installing the power exhaust fan. A hot wire, ground wire, and neutral wire connected to both the service panel and circuit breaker and to the power exhaust fan are required.
  
  
• 4). Following manufacturer's specifications, cut a vent hole in the roof with a power saw or reciprocating saw. Twelve inches square is standard.
  
  
• 5). Mount the mushroom cap, using roofing nails, by tucking it under the head shingles per the manufacturer's flashing specifications. Seal the mushroom cap valance with roofing tar. Every mushroom cap is a bit different; follow the flashing detail exactly to avoid water leakage.
  
  
• 6). From inside the attic, mount the fan and blade assembly with brackets and screws provided by the manufacturer.
  
  
• 7). Turn off the circuit breaker. Wire the electric connections to the thermostat by connecting the neutral to neutral, hot to hot, and ground to ground wires. Support your electric feed line according to local code. Do not use an extension cord.
  
  

Gable End Attic Vent

• 1). Install a decorative louver vent on one vertical end of the attic, if one does not already exist.
  
  
• 2). Mount the fan motor, blade, and thermostat control assembly inside the attic at the louver location, following manufacturer's specifications. Use the brackets and screws provided with the assembly.
  
  
• 3). Turn off the circuit breaker. Wire the electric connections to the thermostat by connecting the neutral to neutral, hot to hot, and ground to ground wires. Support the electric feed line following local building code; do not use an extension cord.