For the installation of a solar attic exhaust fan, you have two options. First, you could hire a professional contractor to handle the job or two you could complete the installation yourself. Today, fans used for attic ventilation are much easier to install so the number of people taking this task on as a DIY project has increased dramatically. To be successful in getting the fan installed properly so it helps cool the hot attic, we have provided some helpful tips.
For starters, you need to measure the attic space that would need a vent system to ensure the appropriate fan is purchased. For this, determine the width of the attic floor, which would then be multiplied by the length of the floor. Then, that number would be multiplied by the number seven, giving you the amount of cubic feet per minute needed, or CFM (the amount of air pushed by the fan). Once you know this number, you want to choose a ventilation fan that exceeds it by 20.
You would also need to determine the size for the intake air louver. For this, multiply the CFM number for the fan by 144. That number would then be divided by 300. Typically, ridge or soffit vent systems exceed this amount in most homes but if you find that your house does not, it would be important to install an intake air vent for the opposite gable. The result would be with this on the exterior wall within the attic but below the roof, the attic fan would be more efficient.
The mounting flange would need to be measured on the inside. The easiest method would be to use a flexible tape measure so you end up with an accurate number. This piece of equipment is designed to encase the sleeve of the fan, the metal housing in which the fan resides, and it helps connect the gable framing. Keep in mind that some ventilation fans are designed without a sleeve. In this case, cross member bars are used to connect to the framing. For the direction of airflow, this would be stamped directly onto the sleeve or motor, pointing in the direction of the mounting flange.
Another part of the installation process for the solar attic exhaust fan is measuring the distance between the gable wall studs in the attic. Using these measurements, a 2×4 wood board would be cut and then nailed to the wall studs to create the opening for framing. You would also be required to measure the distance between top and bottom framing at the opening for the sides of the fan. All of these measures show the need for accuracy for installation of attic ventilation and when done right, the job would be completed quickly and accurately.
Dave Stevens writes more about installing a solar attic exhaust fan at http://www.attic-ventfan.com/solar-attic-exhaust-fan.php