Everything About the Attic

One of the best aspects about installing a solar powered attic fan is the fact that you need no county permits to do this operation. Additionally, you may very happy to find out that it can be installed anywhere.

The way in which a solar fan works makes perfect sense. When the sun shines over the PV modules, it starts working. And the hotter the sun shines, the more air the solar fan starts pumping in. There is a specific temperature that must be reached in order for this fan to start working. As for the investment, this item is probably one of the best investments you can make especially if you live in a hot and dry climate.

You can install this type of fan in a number of different ways. For example one of the popular options is to install it on the roof, in the gable. Either way that you decide to install the fan, it will essentially work in the same way. The most important aspect that is influenced by the mounting option is the ease of installation. An important advantage of the aforementioned gable installation is the fact that it is weather proof, since water is much less likely to pour into the attic.

A good efficient setup involves the fan being placed on the rooftop. This is due to the fact that in this way, you can place the fan exactly near the apex of the roof. The apex of the roof collects the most heat because of the chimney effect, thus making the solar powered fan that much more effective.

Even though placing the fan near the apex might be the most logical thing to do, you need to consider other aspects also. For example, try to locate your fan downwind. This must be done in order to equalize the ventilation in the attic. Also, “hot spots” on your roof that get the most sunlight need to be found. If your house is located in such a way that you can’t get much evening sun, you may need to buy components separately.

And this is where another choice needs to be made: the type of fan. You can choose between two types, distributed units and one piece units. A one piece unit will cost you around $350 and it is the easiest to install. As a matter of fact, it is so easy to install, that you will not even need to step into the attic itself. These are the steps to do it yourself:

1.    Cut a round hole in your house’s roof;
2.    Pull back the shingles;
3.    Gently slide the unit exactly under the shingles and then drop it through the hole;
4.    Finally, you need to seal for weatherproofing.

But there is one potential problem with one piece units. Since the solar modules are always placed on the unit itself, the place where the fan must be placed and the place where it would collect the most sunlight may not be the same. The problem this situation poses is obvious, since the fan can’t pump in a good amount of air if the solar panels don’t get enough sunlight. And this is exactly the situation that is best suited for a distributed system.

As a matter of fact, buying separate components can be much cheaper than buying a one unit fan. A 12VDC fan which is powerful enough for the average house costs somewhere around $100. Additionally, the PV module which is able to run it costs around $130. But there is one catch to all this: the installation procedure and its costs. A hood is needed to be placed over the fan. This will prevent water from getting inside the attic or from soaking the fan. A good problem solver in this situation is to install the fan on a vertical surface, i.e. behind a grate. In this case, you will avoid cutting through the roof, a procedure which always presents a risk of leaks, no matter how small. As a final tip, you can tilt the PV modules to the West. This way, you will get the most of the air movement during the afternoon. If you tilt the modules in such a way that they peak around 2 PM, you will increase the amount of comfort inside your house.