FAQs – Solar Attic Fans
Q. How do I determine the correct sized fan for my attic?
A. This isn’t rocket science. While some manufactures size their fans for a certain number of square feet, we know that is just a guideline. Square footage measures the approximate size of the floor of the attic and doesn’t take into consideration the volume or cubic feet of air in the attic. Then there’s the climate (Arizona vs Maine) and the construction of the building (brick vs wood) and even the color of the roof (dark vs light). After all that, the real answer is “more ventilation is generally better”.
- The SRS-850 (850cfm in full sunlight) is specified for up to 1,200 sq ft. This unit has an 11 watt solar panel. We put the SRS-850 over a garage, in a small attic or as part of a gang of fans in a large attic.
- The SRS-1050 (1,050cfm in full sunlight) is effective for attics up to 1,400 sq ft. This unit has a 15 watt solar panel and is our work-horse fan; the one that we put on most single-family dwellings. We sometimes use two of these if the attic is especially voluminous or has several sections that don’t connect well.
- The SRS-1250 (1,250cfm in full sunlight) is what we recommend for large attics or for commercial applications. This unit has a 20 watt solar panel and may be the most efficient of the SunRise Solar fans.
Solar Attic Fans operate best on a South or West facing roof. If that roof would be the front of your house, SunRise Solar makes a remote solar collector. That means that the smaller solar collector panel could be mounted on the visible part of the roof but the fan itself could be mounted almost anywhere it might not be as obvious.
Q. Why is the SunRise Solar Powered fan better than my electric vent?
A. Let me count the ways…first, the solar fan costs nothing to run. The electric fans are generally noisy and tend to wear out after only a few years of service. ..that’s three. Most electric fans, because they cost money to operate, are coupled with a thermostat. The thermostat turns the fan on when the attic temperature reaches a set temperature, usually 90 or 100 degrees…by that time you’ve lost the battle. How effective is a fan that is trying to cool a 100 degree attic with outside air that is probably 90 degrees. The solar fans come on in the morning when the sun hits the solar panel and begins to draw cool air through the attic. Our customers who had an electric fan in their attics and left it there after we installed the SRS solar powered fan, tell us the electric fans hardly ever come on…the solar fan does all the work. And don’t forget the solar fans are designed to work 12 months a year which means they operate summer and winter…but that’s another question.
Q. Why do I want to vent my attic in the winter?
A. This is a prolific question and one that sometimes breeds controversy. In the winter especially in northern climates, heat and humidity rise into the attic and when they meet the cold air, which is supposed to be in the attic, one thing always occurs…condensation. Condensation starts several events none of which are desirable. The attic insulation becomes laden with moisture which is heavy and causes the insulation to compress and settle over time, making it less effective. The insulation, when its “damp”, causes your furnace to work harder. In the winter, when there is generally less convection or circulation in the attic, moisture tends to build-up giving mold, mildew and fungus an opportunity to start. All of these plus the advantage of inhibiting ice dams (keeping the attic cold verses letting warm air rise in the attic, melting the snow cover near the ridge only to re-freeze further down the roof forming the classic ice dam) are reasons the SunRise Solar Fan benefits you year around.
Q. Does the SunRise Solar Attic Fan qualify for any Federal or State incentives?
We are not tax advisers but the solar fans that we sell qualify for the Solar Federal Tax Credit of 30%. That tax credit includes both the price of the solar product and the labor to install it. Go to www.irs.gov/pub/irs-pdf/f5695.pdf to download the current form.
Q. Where does the fan sit on my roof?
A. The typical installation is on the South or West face of the roof where the sunlight is most direct. If the preferred site happens to be on the front of your home, then we often tell our prospective customers that we need a note from their wife telling us it’s OK to put the fan on the front roof of the house. In actuality, most of the time having a fan on the front is not an issue. But if it is we offer a remote solar collector (the fan can be mounted on the back roof and a much smaller cable-connected solar collector slips onto the sunny front with a much thinner, less noticeable profile).
Q. How can a fan extend the life of my roof?
A. Ask any roofer and they will tell you most roofing material (asphalt shingles and cedar shakes in particular) is built to withstand the intense heat generated by direct sunlight. But when they are also baked from underneath by a 150 degree attic, they just don’t last as long. Keeping your attic cooler helps make your shingles last longer. Ice dams that occur in the winter months are also very hard on your roof…we discussed earlier how a solar powered fan can inhibit the cause of ice dams.
Q. Why don’t you recommend using a thermostat on the SRS fans?
A. Thermostats restrict the hours an attic fan operates…but if the fan operates for free, why limit its runtime? As discussed earlier, more ventilation is usually better…and that is good for both summer and winter months. Since the fan motor is warranted for five years, the concern that it will wear out is hardly worth mentioning. And the solar panel functions whether the fan is running on not, so that’s of little concern. About the only place we do install thermostats is when we put a fan over an un-heated garage that gets terribly hot in the summer. We can help cool it in the summer but making it colder in the winter really is foolish…so we put on the thermostat in those situations.
Q. Where and how do you ship?
A. Standard ground to your door runs $24.00. We are Chicago based so shipping to Alaska, Hawaii and the west coast may be slightly higher.
Q. How do I get my fan installed? How much should it cost?
A. We recommend you hire a competent roofer or someone accustom to working on roofs to install your fan. Instructions are on and in the box. Our guys can install them safely and leak-free in about 45 minutes…cedar and very steep roofs take longer. $100 to install would be a safe estimate.
Q. Do you take returns?
A. Only in the case of a damaged fan and usually that is handled through the shipper. We are pleased to be able to offer these fans at a very fair price. Please help us continue to be able to offer this very “Green” product as inexpensively as we can by making certain it is what you want before you buy.