Solar attic fans save the homeowner
money directly and indirectly. The roof receives direct,
intense rays from the sun. Whether it's a shingled roof
or a metal roof, heat begins building up in the attic space.
Moisture also enters the attic space from daily activities
such as bathing, cooking, laundry, etc. Unless this heat
and moisture is removed, damage can occur in the form of
mold, mildew, and dry rot.
When the attic space overheats,
the shingled roof will heat on the underside of the shingles.
This causes unnecessary wear and tear on your shingles and
you risk wearing them out before the end of the warranty
period. Shingle manufacturers are aware of this and require
ventilation for a correctly installed roof to be covered
under their warranty. This information can be found on the
shingle package wrapper. Most shingle manufactures offer
formulas on their web sites, which determine just how much
attic ventilation is required.
Without adequate attic ventilation,
the manufacturer may consider it an incorrect installation.
What does this mean?
For example, imagine that you
paid $4000.00 for the installation of a 25-year shingle.
However, after 10 years it appears as though the corners
are curled, and it's leaking. You contact the shingle
manufacturer and complain of shingle failure. They examine
the shingles under a microscope and determine that the excessive
wear was from overheating caused by lack of adequate ventilation.
Unfortunately, the warranty only covers correctly installed
shingles, and yours were not. This results in another $4000.00
for a new roof, or your INDIRECT expense for inadequate attic
ventilation.
Here's a quick check for
attic overheating? Inside your home, get a stepladder and
climb it - Be careful! Is the room warmer the further up
you go? This is not a good sign. This means the air conditioner
is working overtime to cool the inside of your home. The
overheating in the attic space causes warming of your ceilings.
That means more electricity usage than necessary, which results
in higher electric bills. Thus, another INDIRECT expense!
Electric Attic Fans use about
350-400 watts of power per day when they run. These fans
have thermostats that are set to start the fan when a certain
temperature is reached, usually around 100 to 115 degrees.
They will then run as long as it takes to get the temperature
back down to 10 or 20 degrees below the starting temperature.
The problem is this - once your attic is allowed to get to
100+ degrees (the starting temp of the electric fan) it will
be a losing battle to cool the attic space, because this
is happening during the hottest part of the day. Also, electric
fans will consume $10-$20/mo. in energy costs just to run
the fan. The DIRECT expense comes in winter when the temperature
outside remains low and the thermostat doesn't cause
the fan to run. As a result, the moisture remains in the
attic with no place to go, causing ice dams, condensation,
mildew, frost, and dry rot.
A correctly installed solar attic
fan runs from sun-up to sundown, summer or winter, at no
cost for operation. With air in the attic space constantly
being circulated during the day, attic space temperatures
remain lower. That means: 1) a cooler attic, 2) less work
for your air conditioner, and 3) your shingles doesn't
deteriorate before their life expectancy. Moisture
escapes, and the risk of damage greatly decreases - thus
preserving the integrity of one of your greatest investments,
your home. Ultimately this results in lower electric bills
and money savings for the homeowner.
The cost of a solar attic fan
will vary depending on the manufacturer, the roofer, and
the area of the country. Usually under $600.00 including
installation is a reasonable rate. Quality and correct installation
are paramount. The solar fan with installation will generally
cost less than the price of an electric fan. Properly installed,
the solar fan will provide years of no-cost operation, while
reducing energy consumption in your home. Because solar fans
are low-voltage, there is no risk of fire.
As you can see, the benefits
of solar attic ventilation are numerous, while making our
world a cleaner and better place to live. Consider letting
the sun cool your hot attic space and save you money!