Solar Attic Fan
The Solar Attic Fan from Natural Light is a simple and environmentally sensible solution that can save both homeowners and commercial facilities money. Powered completely by free solar energy, this sleek and efficient vent is both compact and quiet. Fully operational right from the box, it installs easily, with no electrical wiring, no expensive electrician and city permits. Units come in 10 and 20watt sizes. The 10-watt unit can fully vent up to 1,200 square feet, operating at up to 850 cfms. The Fan can be placed in a range of locations; attics, lofts, workshops, storage sheds, garages, dormers, even barns. The Fan comes with a 25 year warranty on the housing unit, 15 years on the PV module and 5 years on the motor.

Attic venting is an important aspect in maintaining a healthy energy efficient home. Proper venting cools your roof extending the material life and reduces the load on your air conditioning system. Attic venting also increases fresh air circulation which reduces vapor build up generated by every day activities like showering and cooking.

Excess moisture trapped in your attic can cause a variety of problems from rust and rot to increased bacteria and mold counts which can have a direct impact on your respiratory health! Passive vents have been a part of building codes for years. Soffit vents, ridge vents and louvers rely on nature to provide sufficient air pressure and air movement. So the majority of the time your attic is stagnant and continues to build up heat and moisture.
Lowers attic temperature reduces the load on the HVAC System.
The most obvious reason for attic ventilation is to lower attic space temperature during the warmer months. Attic temperatures can exceed 160°F during hot summer days. Proper attic ventilation can reduce those temperatures by up to 50°F. No matter how much insulation is in the attic, heat can still transfer into adjacent living spaces. In fact, extra insulation can actually add to temperature increases because heat is trapped in the insulation. Proper ventilation evacuates this excess heat build-up.
Extends the life of the roofing materials.
Though asphalt shingles are designed to take the abuse of the sun for many years, they are subjected to greater temperatures when the roof decking is allowed to overheat, which is just what happens in an under ventilated attic.

In the cooler months, moisture is the most serious concern. Even with the use of vapor barriers to keep moisture from entering the attic, there are air leaks around ceiling light fixtures, bathroom exhaust fans that allow unwanted moisture into the attic. Moisture condensing on the framing members and the inside of the roof deck can lead to the growth of mold, mildew and rot in the roof deck and framing. A good indicator of moisture problem is rusty roof nails sticking through the roof deck.

Asphalt shingle manufacturers warranties require proper attic ventilation.
Attic ventilation is required in cold environments - it evacuates the warm moist air that heat sources produce. Hot moist air lingering in the attic spaces can condense on the underside of the roof sheathing and rot it out and also causes mold to develop on the interior walls. Cold air in the attic space will not affect the temperature in the adjacent living spaces if properly insulated.

Good ventilation helps prevent ice dams, which begin to form when warm air in the attic melts the snow from beneath and creates runoff that refreezes on the colder eaves.