Start saving
hundreds $$$ on you cooling cost!!!
Master Flow PR1D 1600 Sq Ft.1000 CFM
Power Roof Attic Ventilator
Special Price
$ 600 installed 5 year warranty :replace
existing $500
PR2D 2400 Sq Ft. 1250 CFM Power Roof Attic Ventilator
Discount Price 675 new installllation
5 Year Warranty: Replace existing $575
Table of Contents
What Is An Attic Fan?
Why Should I Install an attic fan ?
How to Determine Which Size Attic fan is
Required?
How much does it cost to Install an attic Fan?
Poor Attic Ventilation Can Ruin Your Insulation,
Destroy Your Shingles, And Raise Your Energy Bills!
Why Take Risks?
It is estimated that 9 out of 10 homes in North America do not
have proper attic ventilation. Why? Because most people are
unaware that attic ventilation can impact the longevity of their
entire home!
For example, in the summer, an improperly ventilated attic can
cause heat to build in excess of 160°F. This superheated air
eventually penetrates the ceiling insulation into the living
area below.
In the winter, various household appliances,
bathtubs, showers, and cooking vapors can contribute to excess
moisture build-up. Improperly ventilated attics will allow this
moisture to collect and cling to the underside of the roof.
There, it will condense and fall, soaking the attic insulation
and reducing its efficiency.
Types of damage that can result include:
• Premature aging of your roofing system (“fried” shingles)
• Warping, cracking, or breaking down of wood framing
• Damage to siding, exterior or interior paint, and wallpaper
• Higher energy costs
A properly ventilated attic can help reduce the load on your air
conditioner by moving the superheated air out of your attic
before it builds up and causes damage.
Additional structural damage can include:
• Roof deck warping and rotting of the wood frame
• Mildew growth
• Buckling of shingles and felt
Finally, attics should be properly ventilated to help prevent
ice dams in cold northern climates. During the winter, ice and
snow on a roof will melt and run down the deck to the cooler
eaves. This run-off can re-freeze, creating an ice dam that will
trap moisture on the roof. The moisture can eventually back up
under the shingles and enter your home — causing hundreds or
thousands of dollars of damage to your ceilings and walls.
Adequate attic ventilation will reduce the amount of initial
melting that occurs on your roof, thereby reducing the chance
that ice dams will form.
|
Proper Attic Ventilation
Proper attic ventilation systems allow a
continuous flow of outside air through the attic (see
illustration
at left), protecting the efficiency of the insulation and
helping to lower temperatures in the living space.
It consists of a balance between air intake
(at your eaves or soffits) and air exhaust
(at or near your roof ridge).
The FHA (Federal Housing Administration) recommends a
minimum
of at least 1 square foot of attic ventilation (both intake and
exhaust) for every 300 square feet of attic space. For example,
if your attic is 900 square feet, you need a total of 3 square
feet of ventilation. This amount is generally divided equally
between intake and exhaust ventilation (i.e., 11/2 feet of
each), to insure proper air flow through the attic.
|
 |
Why
An Attic Fan Should Be Installed
Why ventilate the attic? For very good reasons! The hot summer sun,
beating down on the roof of the average home, makes a veritable furnace
of the space under the roof. Unless some means of dissipating this heat
is provided, it radiates down through the ceiling into the rooms below.
Long after the sun has set and outside temperatures have dropped many
degrees, these rooms continue to receive this accumulation of heat.
The dark, composition roof coverings used on over two-thirds of the
homes built today absorb a greater amount of the sun's heat than did the
wood shingles used in the past century. While insulation retards the
downward flow of this heat, it cannot prevent uncomfortable temperatures
in the rooms below. And unfortunately, though insulation is an asset to
every home, it is as effective at holding heat inside the home in summer
as it is in winter. Natural ventilation of the attic space cannot keep
pace with the heat load being absorbed by the roof.
As summer progresses, there is an increasing accumulation of heat in the
roof, beams, attic, walls and furnishings of the home. While it is true
that some lowering of temperature of the home occurs during the night,
summer nights are too short to allow for anything like an equalization
of temperature.
Therefore, forced ventilation! An attic fan or whole house fan provide a
ready means of dispelling this heat, and not only that, it draws gentle
breezes throughout the house whenever and wherever the home owner wants
them. By the simple touch of a button, cooling breezes are wafted in
through the windows, sweeping the heat and stagnant air up through the
attic and out of the house. With an attic fan, the calm breezeless
nights which weather bureau records prove to be the rule in many
sections of the country, hold no threat of discomfort, no risk of
tossing, sleepless nights.
More or less ventilation for the rooms of the average home is a simple
matter of opening or closing doors and windows. At left, the entire
house is being ventilated. At right, the closing of a hall door has made
the entire capacity of the fan available for cooling the bedrooms.
What Is An Attic
Fan?
The phrase "central heating" is commonly heard and understood. An attic
fan is basically a central ventilating system having three major
components.
First comes the unit itself. This unit consists of the fan blade and its
electric driving motor; an opening in which the blade revolves at slow,
quiet speeds, and the necessary framework, shaft and bearings for
mounting these parts. Fan units are made for both horizontal and
vertical discharge, and will be described.
Since the fan unit is usually located in the attic and it is desired to
draw fresh air into the house through the doors and windows in the lower
floors or basement, the second essential is an opening between the
living quarters of the house and the attic, through which the fan can
draw this cooling air. This opening is usually located in the ceiling of
the upper floor of the house, often directly under the fan unit in the
attic. A grill which will match with the interior trim of the house or a
suitably framed automatic shutter should be inserted in this opening.
Once the fan has drawn air through the house and up into the attic it
must exhaust this air to the outdoors. If there are not sufficient
ventilating louvers or windows already in the attic walls, an outlet
louver of some type must be provided.
When the attic fan is in operation, fresh air enters through any door or
window which is opened. Therefore, the entire house may be ventilated
equally, certain rooms may be closed off from ventilation, or
ventilation may be concentrated in one or two rooms depending upon which
windows and doors are opened or left closed. For example, in extremely
hot weather it is often desirable to have the fan draw all its air
through the one or two most used rooms in order to create a strong
cooling breeze, rather than have a gentle circulation of air thought the
entire house.
During the winter months, the attic fan may be operated when needed to
exhaust cigarette smoke or unpleasant cooking odors from the house. One
or two minutes operation are all that is necessary to completely freshen
the air throughout the house without chilling.
How to
Determine Size Required
When planning an attic fan installation, the first consideration should
be the amount of air which will be needed to properly cool the house.
The quantity necessary will depend on the size of the house, the climate
of the area and even the topography in the immediate vicinity of the
house. The absence of night time breezes or the existence of obstacles
to the natural flow of wind currents will increase the amount of
ventilation capacity that should be provided. No exact rule can be made
governing allowances for the variables of climate and topography. Reason
and experience must dictate these allowances, after cubical content of
the house had been determined. To do this, multiply the floor area of
the living quarters of the house by the height from floor to ceiling.
For houses having more than one floor the volume of each floor should be
computed and added together. Do not include cellars, closets, closed off
garages or porches in this computation, since air will not be circulated
through these areas.
Proper
Planning Reduces Costs
The cost of an attic fan installation will naturally vary
with the size of the house and the type of installation required for the
particular structure. If you need to make a budget, plan on between $700
and $900 per fan required. There are many variables that could effect
the final price, but this is a good ballpark figure. The cost is
somewhat moderate, however, when the resulting years of personal comfort
and large energy reductions are considered. When an architect's services
are obtained in planning a new home, provision can easily be made for
the installation of an attic fan, either at the time the house is built,
or at any later date. Provision for an attic fan will entail little or
no expense at the time the house is constructed, and will eliminate the
need for any structural changes when the fan is installed.
Copyright © 2009 Brown Electric, Masterflow GAF, All rights
reserved.
Revised: 5/2009 |
Attic Fans
available today....call
friendly Brown Electric company electricians today
Toll
free 888 6-POWERS (888) 676-9377
